tag:theconversation.com,2011:/ca/topics/cardiovascular-health-1349/articlesCardiovascular health – The Conversation2024-03-18T19:21:57Ztag:theconversation.com,2011:article/2253542024-03-18T19:21:57Z2024-03-18T19:21:57ZStudy links microplastics with human health problems – but there’s still a lot we don’t know<figure><img src="https://images.theconversation.com/files/582403/original/file-20240317-28-ha8xio.jpg?ixlib=rb-1.1.0&rect=62%2C0%2C7008%2C4668&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/microplastics-hand-air-pollution-aquatic-food-2164471827">Naiyana Somchitkaeo/Shutterstock</a></span></figcaption></figure><p>A <a href="https://www.nejm.org/doi/full/10.1056/NEJMoa2309822">recent study</a> published in the prestigious New England Journal of Medicine has linked microplastics with risk to human health.</p>
<p>The study involved patients in Italy who had a condition called carotid artery plaque, where plaque builds up in arteries, potentially blocking blood flow. The researchers analysed plaque specimens from these patients. </p>
<p>They found those with carotid artery plaque who had microplastics and nanoplastics in their plaque had a higher risk of heart attack, stroke, or death (compared with carotid artery plaque patients who didn’t have any micro- or nanoplastics detected in their plaque specimens). </p>
<p>Importantly, the researchers didn’t find the micro- and nanoplastics <em>caused</em> the higher risk, only that it was correlated with it. </p>
<p>So, what are we to make of the new findings? And how does it fit with the broader evidence about microplastics in our <a href="https://www.science.org/doi/10.1126/sciadv.aax1157">environment</a> and <a href="https://www.sciencedirect.com/science/article/pii/S0160412022001258">our bodies</a>?</p>
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<h2>What are microplastics?</h2>
<p>Microplastics are plastic particles less than five millimetres across. Nanoplastics are less than one micron in size (1,000 microns is equal to one millimetre). The precise size classifications <a href="https://doi.org/10.1016/j.envpol.2018.01.024">are still a matter of debate</a>. </p>
<p>Microplastics and nanoplastics are created when everyday products – including clothes, food and beverage packaging, home furnishings, plastic bags, toys and toiletries – degrade. Many personal care products contain microsplastics in the form of microbeads.</p>
<p>Plastic is also used widely in agriculture, and can degrade over time into microplastics and nanoplastics.</p>
<p>These particles are made up of common polymers such as polyethylene, polypropylene, polystyrene and polyvinyl chloride. The constituent chemical of polyvinyl chloride, vinyl chloride, is <a href="https://wwwn.cdc.gov/TSP/ToxFAQs/ToxFAQsDetails.aspx?faqid=281&toxid=51">considered carcinogenic</a> by the <a href="https://19january2017snapshot.epa.gov/sites/production/files/2016-09/documents/vinyl-chloride.pdf">US Environmental Protection Agency</a>.</p>
<p>Of course, the actual risk of harm depends on your level of exposure. As toxicologists are fond of <a href="https://onlinelibrary.wiley.com/doi/10.1111/bcpt.12622">saying</a>, it’s the dose that makes the poison, so we need to be careful to not over-interpret emerging research.</p>
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Read more:
<a href="https://theconversation.com/australians-are-washing-microplastics-down-the-drain-and-its-ending-up-on-our-farms-223079">Australians are washing microplastics down the drain and it's ending up on our farms</a>
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<h2>A closer look at the study</h2>
<p>This new study in the New England Journal of Medicine was a small cohort, initially comprising 304 patients. But only 257 completed the follow-up part of the study 34 months later. </p>
<p>The study had a number of limitations. The first is the findings related only to asymptomatic patients undergoing carotid endarterectomy (a procedure to remove carotid artery plaque). This means the findings might not be applicable to the wider population.</p>
<p>The authors also point out that while exposure to microplastics and nanoplastics has been likely increasing in recent decades, heart disease rates have been <a href="https://www.ahajournals.org/doi/10.1161/CIRCULATIONAHA.115.015293">falling</a>.</p>
<p>That said, the fact so many people in the study had detectable levels of microplastics in their body is notable. The researchers found detectable levels of polyethylene and polyvinyl chloride (two types of plastic) in excised carotid plaque from 58% and 12% of patients, respectively. </p>
<p>These patients were more likely to be younger men with diabetes or heart disease and a history of smoking. There was no substantive difference in where the patients lived.</p>
<p>Inflammation markers in plaque samples were more elevated in patients with detectable levels of microplastics and nanoplastics versus those without. </p>
<figure class="align-center ">
<img alt="Plastic bottles washed up on a beach." src="https://images.theconversation.com/files/582404/original/file-20240317-18-nz99jb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/582404/original/file-20240317-18-nz99jb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/582404/original/file-20240317-18-nz99jb.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/582404/original/file-20240317-18-nz99jb.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/582404/original/file-20240317-18-nz99jb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/582404/original/file-20240317-18-nz99jb.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/582404/original/file-20240317-18-nz99jb.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">Microplastics are created when everyday products degrade.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/close-waste-beach-1234533793">JS14/Shutterstock</a></span>
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<p>And, then there’s the headline finding: patients with microplastics and nanoplastics in their plaque had a higher risk of having what doctors call “a primary end point event” (non-fatal heart attack, non-fatal stroke, or death from any cause) than those who did not present with microplastics and nanoplastics in their plaque.</p>
<p>The authors of the study note their results “do not prove causality”.</p>
<p>However, it would be remiss not to be cautious. The history of environmental health is replete with examples of what were initially considered suspect chemicals that avoided proper regulation because of what the US National Research Council refers to as the “<a href="https://nap.nationalacademies.org/catalog/12209/science-and-decisions-advancing-risk-assessment">untested-chemical assumption</a>”. This assumption arises where there is an absence of research demonstrating adverse effects, which obviates the requirement for regulatory action. </p>
<p>In general, more research is required to find out whether or not microplastics cause harm to human health. Until this evidence exists, we should adopt the precautionary principle; absence of evidence should not be taken as evidence of absence.</p>
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Read more:
<a href="https://theconversation.com/were-all-ingesting-microplastics-at-home-and-these-might-be-toxic-for-our-health-here-are-some-tips-to-reduce-your-risk-159537">We're all ingesting microplastics at home, and these might be toxic for our health. Here are some tips to reduce your risk</a>
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<h2>Global and local action</h2>
<p>Exposure to microplastics in our home, work and outdoor environments is inevitable. Governments across the globe have started to acknowledge we must intervene. </p>
<p>The <a href="https://www.un.org/en/climatechange/nations-agree-end-plastic-pollution">Global Plastics Treaty</a> will be enacted by 175 nations from 2025. The treaty is designed, among other things, to limit microplastic exposure globally. Burdens are greatest <a href="https://doi.org/10.1016/j.envpol.2022.119957">especially in children</a> and especially those in low-middle income nations. </p>
<p>In Australia, legislation <a href="https://www.epa.vic.gov.au/about-epa/our-programs-and-projects/single-use-plastics-ban">ending single use plastics</a> will help. So too will the increased rollout of <a href="https://recyclingnearyou.com.au/containerdeposit/">container deposit schemes</a> that include plastic bottles.</p>
<p>Microplastics pollution is an area that requires a collaborative approach between researchers, civil societies, industry and government. We believe the formation of a “microplastics national council” would help formulate and co-ordinate strategies to tackle this issue.</p>
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Read more:
<a href="https://theconversation.com/the-problem-with-oodies-hooded-blankets-are-cosy-but-they-are-not-great-for-oceans-or-our-health-163087">The problem with Oodies: hooded blankets are cosy but they are not great for oceans or our health</a>
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<p>Little things matter. Small actions by individuals can also translate to significant overall environmental and human health benefits. </p>
<p>Choosing natural materials, fabrics, and utensils not made of plastic and disposing of waste thoughtfully and appropriately – including recycling wherever possible – is helpful.</p><img src="https://counter.theconversation.com/content/225354/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Mark Patrick Taylor is a full-time employee of EPA Victoria, appointed to the statutory role of Chief Environmental Scientist.
He previously received funding via an Australian Government Citizen Science Grant (2017-2020), CSG55984 ‘Citizen insights to the composition and risks of household dust’ (the DustSafe project). Outputs from this project included published work on microplastics with Drs Neda Sharifi Soltani and Scott Wilson who were at Macquarie University at that time.
</span></em></p><p class="fine-print"><em><span>Scott P. Wilson works for the Australian Microplastic Assessment Project run by the not for profit organisation the Total Environment Centre. He has previously received funding from the NSW EPA for research into microplastic source tracking in Deewhy Lagoon and for developing a Microlitter Reduction Framework. </span></em></p>Microplastics are created when everyday products – including clothes, food and beverage packaging, home furnishings, plastic bags, toys and toiletries – degrade.Mark Patrick Taylor, Chief Environmental Scientist, EPA Victoria; Honorary Professor, School of Natural Sciences, Macquarie UniversityScott P. Wilson, Research Director, Australian Microplastic Assessment Project (AUSMAP); Honorary Senior Research Fellow, School of Natural Sciences, Macquarie UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2230802024-02-28T22:11:57Z2024-02-28T22:11:57ZStop breaking women’s hearts at work: 7 ways to make workplaces better for cardiovascular health<figure><img src="https://images.theconversation.com/files/578772/original/file-20240228-20-3fdqgt.jpg?ixlib=rb-1.1.0&rect=1581%2C73%2C6597%2C4329&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Research shows women are at higher risk for burnout and psychological, emotional and physical stress in the workplace in comparison to their male counterparts.</span> <span class="attribution"><span class="source">(Shutterstock)</span></span></figcaption></figure><p>Prominent heart health messaging focuses on the <a href="https://www.heartandstroke.ca/stroke/recovery-and-support/make-healthy-choices#:%7E:text=Be%20more%20active,disease%20and%20stroke%20by%2030%25.">role of lifestyle behaviours</a> (such as physical activity and nutrition) in cardiovascular health. However, the role of <a href="https://www.who.int/health-topics/social-determinants-of-health#tab=tab_1">social determinants of health</a> (or SoDH) — which include sex, gender, poverty, environment — is also well established. SDoH not only directly impact <a href="https://doi.org/10.1161/circresaha.121.319811">risk and progression</a> of heart disease, <a href="https://doi.org/10.1016/j.ajmo.2023.100047">but also health outcomes</a>.</p>
<p>Certain types of heart disease are <a href="https://www.heartandstroke.ca/what-we-do/media-centre/news-releases/system-failure-womens-heart-and-brain-health-are-at-risk">significantly more common in women</a>, compared to men. Moreover, compared with their non-Black counterparts, heart health for Black women is differentiated by a heavier burden of traditional risk factors, earlier development of the disease and nearly 20 per cent higher <a href="https://onlinecjc.ca/article/S0828-282X(23)01619-7/abstract#:%7E:text=Compared%20with%20their%20nonblack%20counterparts,higher%20rates%20of%20cardiovascular%20mortality.">rates of cardiovascular mortality</a>. </p>
<h2>Women, work and heart health</h2>
<p>Canadians spend an average of 7.5 hours per day at work, translating to roughly half of our waking hours. Several researchers have shown a relationship between <a href="https://www.hsph.harvard.edu/news/press-releases/increasing-workplace-flexibility-associated-with-lower-risk-of-cardiovascular-disease/">workplace and heart health</a>. For instance, <a href="https://doi.org/10.2105/ajph.2023.307413">research has linked</a> increased workplace flexibility (hybrid models, flexible schedule) with lower risk of cardiovascular disease. </p>
<p>Research also shows women are at higher risk for burnout and psychological, emotional and physical stress in the workplace <a href="https://www.cnbc.com/2023/03/14/burnout-is-on-the-rise-gen-z-millennials-and-women-are-the-most-stressed.html#:%7E:text=Two%20types%20of%20people%2C%20however,burnout%20than%20men%20(37%25)">in comparison to their male counterparts</a>. This disproportionate burden has been attributed to several factors in and outside the workplace, inextricably linked to <a href="https://doi.org/10.3389/fpsyg.2015.01400">gender roles, sexism, racism, ageism and misogyny</a>. For instance, women are more likely to experience gender-based violence, assumptions about gender-roles, and higher cognitive and emotional workload in and out of work. </p>
<figure class="align-center ">
<img alt="A woman bringing a mug to an older woman" src="https://images.theconversation.com/files/578728/original/file-20240228-22-q2iddp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/578728/original/file-20240228-22-q2iddp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/578728/original/file-20240228-22-q2iddp.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/578728/original/file-20240228-22-q2iddp.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/578728/original/file-20240228-22-q2iddp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/578728/original/file-20240228-22-q2iddp.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/578728/original/file-20240228-22-q2iddp.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">Many women balance paid work with gendered labour in the home and care-taking roles.</span>
<span class="attribution"><span class="source">(Shutterstock)</span></span>
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<p>Once again, these burdens are <a href="https://www.mckinsey.com/ca/%7E/media/mckinsey/locations/north%20america/canada/gender%20diversity%20at%20work/gender_diversity_at_work_in_canada.pdf">higher in equity-deserving groups</a>, especially for women experiencing <a href="https://www.mckinsey.com/featured-insights/diversity-and-inclusion/women-in-the-workplace">intersectional forms of discrimination</a>, such as <a href="https://canadianwomen.org/wp-content/uploads/2021/04/Resetting-Normal-Gender-Intersectionality-and-Leadership-Report-Final-EN.pdf">racism, colonialism, ableism and homophobia</a>. </p>
<p>It should not come as a surprise then that almost 90 per cent of reported <a href="https://www.health.harvard.edu/heart-health/takotsubo-cardiomyopathy-broken-heart-syndrome#:%7E:text=More%20than%2090%25%20of%20reported,no%20long%2Dterm%20heart%20damage.">stress-induced heart disease</a> — or “<a href="https://www.heart.org/en/news/2021/10/13/broken-heart-syndrome-is-on-the-rise-especially-among-older-women">broken heart syndrome</a>” — is found among women, and five per cent of women suspected of having a heart attack actually have this disorder.</p>
<p>Women are often the heart of their communities, and assume multiple, and intersecting, gendered social roles. For instance, many balance paid work, with <a href="https://cdn.dal.ca/content/dam/dalhousie/pdf/diff/ace-women-health/Healthy%20Balance/ACEWH_hbrp_thinking_it_through_women_work_caring_new_millennium.pdf">gendered labour in the home and in care-taking roles</a>. To make matters worse, women are then <a href="https://hbr.org/2022/04/stop-framing-wellness-programs-around-self-care">bombarded with wellness and self-management messaging</a> that tells them they are <a href="https://www.psychologytoday.com/ca/blog/the-psychology-of-weight-loss/202308/going-on-vacation-wont-cure-your-burnout">responsible for managing stress</a> and <a href="https://www.psychologytoday.com/ca/blog/the-psychology-of-weight-loss/202306/the-burnout-burger">risk in a “healthy” way</a>.</p>
<p>In terms of workplace health, women and equity-deserving groups have been compared to the “canary in the mine.” Canaries were traditionally used in coal mines to detect the presence of carbon monoxide. The bird would succumb to the toxicity before the miners, thereby providing time to take action. </p>
<p>However, psychologists Christina Maslach and Michael P. Leiter <a href="https://www.hup.harvard.edu/books/9780674251014">make an important point</a>: No one ever declared that the canaries needed to be more resilient or do more self-care to be less susceptible to the influence of carbon monoxide.</p>
<p>Women make up over half of the population, yet continue to be <a href="https://doi.org/10.1016%2Fj.neuron.2021.06.002">under-represented in the workplace in several ways</a>, including <a href="https://canadianwomen.org/the-facts/women-and-leadership-in-canada/#:%7E:text=Women%20are%2030%25%20less%20likely,%2C%20report%20finds%2C%202017">leadership and positions of influence</a>. </p>
<h2>Creating heart-healthy workplaces</h2>
<figure class="align-center ">
<img alt="A woman at a desk looking at a tablet" src="https://images.theconversation.com/files/578730/original/file-20240228-24-sbksv1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/578730/original/file-20240228-24-sbksv1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=379&fit=crop&dpr=1 600w, https://images.theconversation.com/files/578730/original/file-20240228-24-sbksv1.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=379&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/578730/original/file-20240228-24-sbksv1.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=379&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/578730/original/file-20240228-24-sbksv1.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=476&fit=crop&dpr=1 754w, https://images.theconversation.com/files/578730/original/file-20240228-24-sbksv1.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=476&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/578730/original/file-20240228-24-sbksv1.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=476&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">Hybrid work models can increase productivity and workers’ locus of control and support flexible hours.</span>
<span class="attribution"><span class="source">(Shutterstock)</span></span>
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<p>Workplaces can have a positive impact on women’s health by ensuring knowledge about women and heart disease is translated into actions that support prevention and treatment. Here are seven evidence-based recommendations for co-creating heart-healthy workplaces:</p>
<ol>
<li><p><strong>Flexible hours</strong>: <a href="https://doi.org/10.1177/0002716211415608">Inflexible work schedules</a> have been shown to increase stress for <a href="https://workplaceinsight.net/working-mothers-disproportionately-more-stressed-study-claims/">women and families</a> — including stressors transmitted to children. Effective “flex hours” initiatives (for example, flex hours to support physical activity) show <a href="https://www.nhlbi.nih.gov/news/2023/workplace-flexibility-may-support-cardiovascular-health">positive impact on workers’ heart health</a>, physical activity and sleep patterns, especially in adults ages 45 and older and for those who had increased cardiovascular disease risks.</p></li>
<li><p><strong>Flexible hybrid work models</strong>: Evidence on hybrid work models has grown exponentially since March 2020. It appears that when using a non-fixed, worker-led approach, hybrid work models can <a href="https://www.hsph.harvard.edu/news/press-releases/increasing-workplace-flexibility-associated-with-lower-risk-of-cardiovascular-disease/">increase productivity, workers’ locus of control and support flexible hours</a>. Research supports that women are more likely to use this option, when offered, but also highlights that when employers fail to monitor impact, or properly design jobs for hybrid and remote working, <a href="https://www.theguardian.com/society/2022/sep/25/hybrid-working-may-hold-back-womens-careers-say-managers">hybrid work models can augment gender pay and promotion gaps</a>. </p></li>
<li><p><strong>Invest in psychological safety</strong>: A <a href="https://theconversation.com/fostering-psychological-safety-in-the-workplace-4-practical-real-life-tips-based-on-science-204661">psychologically safe workplace</a> is where employees feel comfortable taking risks and being themselves without fear of judgement, lateral violence (for example stonewalling, bullying) or negative consequences. Psychological safety is positively associated with workplace engagement, innovation, job performance and job satisfaction — all desirable outcomes for institutions, organizations, the bottom line, clients and the community. </p></li>
<li><p><strong>Offer health benefits</strong>: Mandatory benefits, also known as statutory benefits, are <a href="https://novascotia.ca/lae/employmentrights/docs/labourstandardscodeguide.pdf">required by Canadian employment law</a>. They include provincial health-care coverage, pension contributions, employment insurance, survivor insurance and workers’ compensation insurance. <a href="https://velocityglobal.com/resources/blog/employee-benefits-in-canada">Supplementary benefits</a> help attract and retain workers. Examples include dental care, medication insurance, disability insurance and many complementary medicine services. These <a href="https://doi.org/10.1007%2FBF03403639">supplementary benefits</a> have been associated with <a href="https://doi.org/10.1001/jamanetworkopen.2022.33020">improved health outcomes</a>, and <a href="https://www.who.int/news-room/fact-sheets/detail/universal-health-coverage-(uhc)">reduced chronic disease risk</a>.</p></li>
<li><p><strong>Invest in programs supporting health promotion</strong>: In addition to the examples above, <a href="https://www.cdc.gov/workplacehealthpromotion/initiatives/resource-center/pdf/WHRC-Workplace-Best-Practices-for-Heart-Healthy-Employees-508.pdf">workplaces can invest</a> in programming that supports health-promoting behaviours in and out of work. <a href="https://doi.org/10.1097/jom.0000000000000467">Such programming</a> has been associated with workplace satisfaction, productivity and favourable health-related outcomes. Additional examples of health promotion include health risk appraisals, lunch and learns, flexible and inclusive leave options, and time off for leisure activities, spiritual practices, volunteering or community engagement. </p></li>
<li><p><strong>Engage in collective conflict resolution strategies</strong>: Evidence supports that <a href="https://www.ncbi.nlm.nih.gov/books/NBK470432/">collaborative conflict resolution</a> approaches, like mediation, can provide a positive learning opportunity for those involved. This encourages workers to find a solution together, <a href="https://demlegaleagle.com/blog/2020/12/3-ways-workplace-mediation-may-beat-discipline/">rather than via formal disciplinary action</a>, where the root causes of conflict often go unaddressed.</p></li>
<li><p><strong>Commit to policy, procedure and protocols that combat ‘isms’</strong>: Ibram X. Kendi’s book, <a href="https://www.ibramxkendi.com/how-to-be-an-antiracist"><em>How To Be An Antiracist</em></a>, provides rationale and examples for how to ensure policy and procedures are anti-racist. Adopting this approach requires a significant, but worthwhile investment, learning and unlearning, but gains can be made through small changes. Workplaces can also adopt policies that combat other forms of discrimination, including ageism and sexism. For instance, several employers have started to <a href="https://www.indeed.com/career-advice/resumes-cover-letters/stay-at-home-mom-resume">encourage applicants</a> to <a href="https://www.forbes.com/sites/forbescoachescouncil/2023/02/24/how-stay-at-home-parents-returning-to-work-can-overcome-common-barriers/?sh=f500d7f2c091">report “stay at home mom” as part of their work experience</a>, and the several transferable skills this experience offers.</p></li>
</ol>
<figure class="align-right ">
<img alt="A yellow canary perched on a branch" src="https://images.theconversation.com/files/578731/original/file-20240228-18-alxd70.png?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/578731/original/file-20240228-18-alxd70.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=545&fit=crop&dpr=1 600w, https://images.theconversation.com/files/578731/original/file-20240228-18-alxd70.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=545&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/578731/original/file-20240228-18-alxd70.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=545&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/578731/original/file-20240228-18-alxd70.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=685&fit=crop&dpr=1 754w, https://images.theconversation.com/files/578731/original/file-20240228-18-alxd70.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=685&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/578731/original/file-20240228-18-alxd70.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=685&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Integrating health and safety strategies is a better option for workers than waiting until the ‘canary’ expires.</span>
<span class="attribution"><span class="source">(Pixabay)</span></span>
</figcaption>
</figure>
<p>Rather than waiting until the canary in the workplace coal mine expires, <a href="https://doi.org/10.1097/jom.0000000000000467">evidence shows</a> there are options available to integrate health and safety strategies that achieve measurable benefits to enhance the overall health and well-being of workers, their families and the community. </p>
<p>In acknowledging that factors like the built environment, social and health systems, and outdated policies are the problems needing to be addressed — rather than people, including women, those living with disability, and equity-deserving groups — we take a step towards healthier, safer and more accessible workplaces.</p><img src="https://counter.theconversation.com/content/223080/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Shannan M. Grant has received funding from Diabetes Canada, Dietitians of Canada and currently holds funding from Medavie, Tri-Council Funding Programs, Canadian Foundation for Dietetic Research, IWK Health, Mount Saint Vincent University. She is affiliated with Mount Saint Vincent University, IWK Health, Dalhousie University, Dietitians of Canada, Diabetes Canada, People in Pain (PIPN), and Dr. Lee-Baggley and Associates.</span></em></p><p class="fine-print"><em><span>Dayna Lee-Baggley dislosures: Consulting fees from: Bausch Health, Novo Nordisk; Clinical advisory committee: Tobacco Free Nova Scotia; Royalties: New Harbinger Publications; Funded by: Workplace Harassment and Violence Prevention Fund, Employment and Social Development Canada, Government of Canada; Canadian Foundation for Dietetic Research, Research Grants; Owner or co-owner: Dr. Lee-Baggley and Associates Inc and ImpACT Workplace Solutions Inc.
</span></em></p><p class="fine-print"><em><span>Jacquie Gahagan receives funding from SSHRC and CIHR.</span></em></p><p class="fine-print"><em><span>Barb Hamilton-Hinch, Jessica Mannette, and Leigh-Ann MacFarlane do not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Acknowledging that factors like the built environment, social and health systems, and outdated policies are the problems — rather than people — is a step towards healthier and safer workplaces.Shannan M. Grant, Associate Professor, Registered Dietitian, Department of Applied Human Nutrition, Faculty of Professional Studies, Mount Saint Vincent UniversityBarb Hamilton-Hinch, Associate Professor, School of Health and Human Performance, and Assistant Vice Provost of Equity and Inclusion, Dalhousie UniversityDayna Lee-Baggley, Adjunct professor, Department of Family Medicine & Department of Psychology and Neuroscience, Dalhousie UniversityJacquie Gahagan, Full Professor and Associate Vice-President, Research, Mount Saint Vincent UniversityJessica Mannette, Research Assistant, Department of Psychology, Saint Mary’s UniversityLeigh-Ann MacFarlane, Educational Developer, Mount Saint Vincent UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2225162024-02-11T13:50:24Z2024-02-11T13:50:24ZIt’s time for a heart-to-heart about women’s cardiovascular health, unique risk factors and symptoms<p>Cardiovascular disease — also called heart disease — is a condition affecting the heart and blood vessels, and is the leading cause of death among <a href="https://doi.org/10.1016/S0140-6736(21)00684-X">women worldwide</a>. In fact, a women dies of heart disease every <a href="https://www.heartandstroke.ca/-/media/pdf-files/canada/2018-heart-month/hs_2018-heart-report_en.ashx#">20 minutes in Canada</a>. </p>
<p>Although cardiovascular disease is often considered a disease of men, women are more likely to die from a <a href="https://doi.org/10.1016/j.cjco.2020.10.009">heart attack</a> when compared with men. This fact often surprises women and even their health-care providers. Many women are not aware that heart disease is a significant health threat to them, but the reality is that <a href="https://www.heartandstroke.ca/-/media/pdf-files/canada/2018-heart-month/hs_2018-heart-report_en.ashx#">five times</a> as many women die from heart disease as breast cancer. </p>
<p>Despite dramatic improvements in management of cardiovascular disease over time, the death rate due to heart disease is <a href="https://doi.org/10.1093/ehjqcco/qcaa099">actually increasing</a> in women, especially those under age 65. It has become clear that <a href="https://www.heartandstroke.ca/-/media/pdf-files/canada/2018-heart-month/hs_2018-heart-report_en.ashx#">women remain</a> under-researched, under-diagnosed, under-treated, under-supported an under-aware of their cardiovascular risk. </p>
<p>That’s why it is critical that moving forward, we recognize that women’s hearts are unique. Additionally, there is an urgent need to start a conversation with Canadians to improve awareness of women’s heart health to help save the lives of mothers, sisters, daughters, family and friends. </p>
<h2>Women’s hearts are different</h2>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/574087/original/file-20240207-26-jtv39j.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A group of women wearing red and with the title Wear Red Canada wearredcanada.ca" src="https://images.theconversation.com/files/574087/original/file-20240207-26-jtv39j.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/574087/original/file-20240207-26-jtv39j.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/574087/original/file-20240207-26-jtv39j.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/574087/original/file-20240207-26-jtv39j.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/574087/original/file-20240207-26-jtv39j.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/574087/original/file-20240207-26-jtv39j.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/574087/original/file-20240207-26-jtv39j.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">On Feb. 13, Wear Red Canada raises awareness for women’s cardiovascular health.</span>
<span class="attribution"><span class="source">(Canadian Women's Heart Health Centre)</span></span>
</figcaption>
</figure>
<p>From the outside, women’s hearts may look the same as men’s, but there are important differences. Specifically, women experience unique events over the course of their lifespan which may impact their cardiovascular health. For example, an individual’s <a href="https://doi.org/10.1016/j.cjco.2021.09.013">menstrual health and patterns, or conditions related to fertility</a>, such as polycystic ovary syndrome or endometriosis, may influence her cardiovascular well-being. </p>
<p>Pregnancy complications, such as hypertensive disorders of pregnancy and gestational diabetes, can also play a role in cardiovascular health. Finally, menopause factors, including timing of menopause and menopause-related treatments, may also be indicators of cardiovascular health. </p>
<p>In addition to such risk factors that are inherent to the female experience, women are <a href="https://www.cjcopen.ca/cms/attachment/a2d5edd9-5a5a-41d4-b824-7749ae0d9a67/gr1.jpg">disproportionately impacted by other risk factors for heart disease</a>. These risk factors may include conditions such as depression, chronic kidney disease and autoimmune disease. </p>
<p>Women need to not only be aware of how their risk for heart disease may change across the lifespan, but also how they can be proactive and make informed decisions regarding their heart health at all stages of life. </p>
<h2>Heart attack symptoms</h2>
<p>Early heart attack symptoms are missed in up to <a href="https://www.heartandstroke.ca/-/media/pdf-files/canada/2018-heart-month/hs_2018-heart-report_en.ashx#:%7E:text=Every%2020%20minutes%20a%20woman%20in%20Canada%20dies%20from%20heart%20disease.&text=Five%20times%20as%20many%20women%20die%20from%20heart%20disease%20as%20breast%20cancer.&text=Two%2Dthirds%20of%20heart%20disease%20clinical%20research%20focuses%20on%20men.&text=Women%20who%20have%20a%20heart,heart%20attack%20compared%20to%20men.">78 per cent</a> of women, in part related to the fact that women may present with different symptoms than men. </p>
<p>Similar to men, women often present with chest pain or discomfort, though they may have additional or <a href="https://doi.org/10.1161/CIRCULATIONAHA.117.031650">alternative symptoms</a> such as jaw, neck or back pain, shortness of breath, nausea, indigestion and extreme fatigue. In fact, women are more likely to present with three or more symptoms in addition to chest pain when having a heart attack. </p>
<p>An awareness of the differences in heart attack symptoms may lead to improved recognition and timely care for women. </p>
<p>Recognizing that women can have different cardiovascular risk factors, symptoms and even types of heart disease can be scary and overwhelming. However, there is good news! It is estimated that approximately <a href="https://world-heart-federation.org/what-we-do/prevention/#:%7E:text=An%20estimated%2080%25%20of%20cardiovascular,and%20">80 per cent</a> of cardiovascular disease is preventable.</p>
<h2>Reducing heart risks</h2>
<figure class="align-center ">
<img alt="Group of women outdoors in athletic clothes carrying yoga mats" src="https://images.theconversation.com/files/574724/original/file-20240209-18-8p1xc4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/574724/original/file-20240209-18-8p1xc4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/574724/original/file-20240209-18-8p1xc4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/574724/original/file-20240209-18-8p1xc4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/574724/original/file-20240209-18-8p1xc4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/574724/original/file-20240209-18-8p1xc4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/574724/original/file-20240209-18-8p1xc4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">It’s estimated that about 80 per cent of heart disease is preventable.</span>
<span class="attribution"><span class="source">(Shutterstock)</span></span>
</figcaption>
</figure>
<p>There are many steps that you can take to reduce your risk of heart disease. <a href="https://www.heartandstroke.ca/heart-disease/risk-and-prevention/lifestyle-risk-factors">Staying active</a> and moving every day, and even small steps to reduce sedentary time can be beneficial. </p>
<p>Eating a healthy and <a href="https://www.heartandstroke.ca/healthy-living/healthy-eating">balanced diet</a> is also important. Aim to eat a variety of healthy foods and try to limit highly processed foods and salt. How you eat also matters: listen to your body by eating when you are hungry, but stopping once you are satisfied. </p>
<p>Living free from commercial tobacco and vaping, reducing alcohol intake and managing stress are also key ways to reduce your risk. Finally, take your medications as prescribed and have regular check-ups with your health-care providers.</p>
<h2>Wear red and learn more</h2>
<p>On Feb. 13, we invite you to celebrate <a href="https://wearredcanada.ca">Wear Red Canada</a> to raise awareness for women’s cardiovascular health, hosted by the <a href="http://cwhhc.ottawaheart.ca/national-alliance/cwhha">Canadian Women’s Heart Health Alliance</a> and the <a href="https://cwhhc.ottawaheart.ca/">Canadian Women’s Heart Health Centre</a>. Wear red and share selfies or pictures of your participation by using the hashtag #HerHeartMatters and tagging @WearRedCanada to help spread this important message. </p>
<p>Attend free <a href="https://wearredcanada.ca/educational-webinars">presentations and webinars</a> by Canadian experts, join the <a href="https://raceroster.com/events/2024/77122/wear-red-canada-movement-challenge?utm_source=Cyberimpact&utm_medium=email&utm_campaign=Countdown-1-Week-Until-the-Wear-Red-Canada-Movement-Challenge-Begins--Register-Today">Wear Red Canada Movement Challenge</a> and take part in local events. </p>
<p>By wearing red on Feb. 13 and starting conversations about women’s heart health, we all can increase awareness and improve the heart health of the women we love.</p><img src="https://counter.theconversation.com/content/222516/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Nabilah Gulamhusein has received funding from the Canadian Institutes of Health Research through the Canada Graduate Scholarship - Master’s.</span></em></p><p class="fine-print"><em><span>Sandi Dumanski receives funding from the Canadian Fertility and Andrology Society and the Kidney Foundation.</span></em></p>It’s important for women to not only be aware of their risk for heart disease, but also how they can be proactive and make informed decisions regarding their heart health at all stages of life.Nabilah Gulamhusein, PhD Student, Medical Sciences, University of CalgarySandi Dumanski, Assistant Professor, Department of Medicine, University of CalgaryLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2215162024-01-22T14:55:17Z2024-01-22T14:55:17ZIt’s okay to run slowly – in fact it has plenty of benefits<figure><img src="https://images.theconversation.com/files/570627/original/file-20240122-16-1hvdhh.jpg?ixlib=rb-1.1.0&rect=5%2C0%2C3952%2C2604&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The perfect slow running pace is one where you can still easily have a conversation.</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/family-exercising-jogging-together-outdoor-park-2202219503">Lopolo/ Shutterstock</a></span></figcaption></figure><p>Runners are obsessed with time. Amateur or professional, for most avid runners the aim is to get faster – constantly training in order to shave even just a couple of seconds off their marathon time or 5K pace.</p>
<p>But one running trend that’s started to gain a foothold in recent years is that of <a href="https://www.womensrunning.com/training/beginner/slow-running-benefits/">“slow running”</a>. The idea behind the <a href="https://slowafrunclub.com/">slow running movement</a> is that anyone can run – no matter your ability or how fast you run.</p>
<p>Fans of this approach say it has many benefits – not just for your health but also in <a href="https://advice.decathlon.ca/slow-running-why-its-good-for-you">how enjoyable</a> you find running. Research agrees, with evidence showing slow running may in some ways be more beneficial than training at higher intensities.</p>
<p>When we think of elite runners such as Eliud Kipchoge or Kelvin Kiptum, we might assume that to set world records, they primarily train at these record-setting paces. But surprisingly, elite runners spend around 80% of their time training at what’s termed <a href="https://journals.humankinetics.com/view/journals/ijspp/17/6/article-p820.xml">zone 2 running</a> – a running pace which raises your heart rate, but is still slow enough that you can hold a conversation. Only around 20% of their training is done in the higher intensity zones, which are closer to their race pace. </p>
<p>The reason for this relates to the amount of stress that training puts on the body. As running speed increases, the more strain the body is put under. The more strain the body is put under, the <a href="https://www.researchgate.net/profile/David-Nieman/publication/20868569_The_Effects_of_Moderate_Exercise_Training_on_Natural_Killer_Cells_and_Acute_Upper_Respiratory_Tract_Infections/links/55670c0d08aeab77721e639f/The-Effects-of-Moderate-Exercise-Training-on-Natural-Killer-Cells-and-Acute-Upper-Respiratory-Tract-Infections.pdf">greater a person’s risk</a> of illness, infection and <a href="https://bjsm.bmj.com/content/bjsports/early/2016/07/25/bjsports-2016-096040.full.pd">injury</a>. By reducing the amount of time they spend at higher intensities, athletes limit their chances of missing out on training due to illness and injury.</p>
<p>But there’s more to this approach than just reducing the risk of injury and illness. A fundamental aspect of training is developing what’s known as “base”. This term describes the physiological foundations that underpin all training adaptations. For the endurance runner, this refers to their baseline cardio-respiratory fitness on to which their higher intensity adaptations can be built.</p>
<p>Think of it like a pyramid, which has a solid base on which the rest of the structure is built. The bigger the base, the taller the pyramid can be.</p>
<figure class="align-center ">
<img alt="A group of professional marathon runners, including Eliud Kipchoge, at the London marathon." src="https://images.theconversation.com/files/570628/original/file-20240122-21-bt6rl3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/570628/original/file-20240122-21-bt6rl3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/570628/original/file-20240122-21-bt6rl3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/570628/original/file-20240122-21-bt6rl3.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/570628/original/file-20240122-21-bt6rl3.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/570628/original/file-20240122-21-bt6rl3.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/570628/original/file-20240122-21-bt6rl3.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Even the world’s fastest runners spend most of their time going slow.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/london-april-26-elite-men-eliud-272991692">Cristian Teichner/ Shutterstock</a></span>
</figcaption>
</figure>
<p>The same holds true for training. The better your base, the more capable you will be when working at <a href="https://link.springer.com/article/10.2165/00007256-200029060-00001">higher intensities</a>. </p>
<p>Your base is developed during slow (zone 2) running, where physiological stress is <a href="https://www.tandfonline.com/doi/full/10.1080/02640414.2011.596217">relatively low</a>. But even though the heart isn’t under very much stress during zone 2 running, the amount of oxygenated blood leaving the heart each beat will be <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1725174/pdf/v039p00190.pdf">close to or at its maximum</a> amount. </p>
<p>This is important because while the pumping capacity of the heart adapts to training, higher intensities do not increase this gain. Developing a strong base allows for more oxygen to be delivered to the working muscles per heartbeat, which is crucial to running success.</p>
<p>Not only that, but running at slow paces causes the body to use <a href="https://journals.humankinetics.com/view/journals/ijspp/15/3/article-p375.xml">stored fat for energy</a> – as opposed to relying on carbohydrate stores that come from the foods we eat. </p>
<p>Burning fat is metabolically a far more efficient process, as the amount of energy derived from a single molecule of fat <a href="https://www.nature.com/articles/s42255-020-0251-4">far exceeds</a> the amount from a molecule of carbohydrate. This means runners will use less energy overall – and will be less fatigued and better able to run fast on race day.</p>
<p>Studies have shown that gains in VO2 max (oxygen capacity) and race speed are <a href="https://journals.humankinetics.com/view/journals/ijspp/5/3/article-p276.xml">around 1% greater</a> for athletes who spend more time slow running. Crucially, the gains in aerobic base are around <a href="https://journals.humankinetics.com/view/journals/ijspp/5/3/article-p276.xml">five times greater</a> in slow runners compared to athletes who more frequently use high-intensity runs.</p>
<p>Even if you aren’t an athlete, aiming to keep most of your runs at a <a href="https://www.jssm.org/jssm-22-263.xml%3EFulltext">low intensity</a> may <a href="https://www.jacc.org/doi/abs/10.1016/j.jacc.2014.04.058">still be optimal</a>. </p>
<h2>Slow and steady</h2>
<p>If you’re keen to give slow running a try, the most important thing is your pace. How exactly do you know you’re at the right speed to be classed as slow running?</p>
<p>Some scientists divide running pace into five or six different zones. Physiologically, zone 2 is defined as occurring below the <a href="https://www.researchgate.net/profile/Timothy-Noakes/publication/21553500_Effects_of_training_on_lactate_production_and_removal_during_progressive_exercise_in_humans/links/5407408f0cf2c48563b29d94/Effects-of-training-on-lactate-production-and-removal-during-progressive-exercise-in-humans.pdf">lactate threshold</a> – the point where lactate (an acid the body produces when it begins to burn carbohydrates for energy) first starts to appear in the blood. </p>
<p>In simple terms, this should be at a speed where you can still hold a conversation and your heart rate is only around 70% of your maximum. If you find conversation <a href="https://journals.physiology.org/doi/pdf/10.1152/physrev.2000.80.2.681">starts to become difficult</a> then you should slow your pace down.</p>
<p>If you’re running on your own, you can try the <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10331140/">talk test</a>. If you can sing out loud to yourself without struggling to catch your breath, you’re in the right zone. If you do struggle, you’re at too high an intensity and lactate will start to build up in your muscles (which may make your legs feel heavy).</p>
<p>Slow running offers many benefits – both for your body and your mental health. So if you’re someone who’s always been shy about your slow running pace, perhaps this will inspire you to put on your trainers and give running a go.</p><img src="https://counter.theconversation.com/content/221516/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Jonathan Melville works for breakaway coaching and analytics. </span></em></p><p class="fine-print"><em><span>Dan Gordon and Matthew Slater do not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Slow running may burn more fat compared to running at a faster pace.Dan Gordon, Associate Professor, Cardiorespiratory Exercise Physiology, Anglia Ruskin UniversityJonathan Melville, PhD Candidate, Sport and Exercise Science, Anglia Ruskin UniversityMatthew Slater, PhD Candidate, Anglia Ruskin UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2174292023-12-11T13:12:20Z2023-12-11T13:12:20ZHow do pacemakers and defibrillators work? A cardiologist explains how they interact with the electrical system of the heart<figure><img src="https://images.theconversation.com/files/564019/original/file-20231206-17-jlxwsq.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C2113%2C1419&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Electrocardiograms, or ECGs, record the electrical activity of your heart. </span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/heart-rate-monitor-royalty-free-image/523791776">Randy Faris/The Image Bank via Getty Images</a></span></figcaption></figure><p>Your heart’s job is to keep your pulse steady to pump blood throughout your body. Sometimes your heart rate is slower when you’re relaxing, and sometimes it’s faster when you’re exercising or stressed. If your heart’s ability to keep the beat starts to go awry, <a href="https://scholar.google.com/citations?view_op=list_works&hl=en&user=IM1QEMIAAAAJ">cardiac electrophysiologists like me</a> look for outside help from an implantable device.</p>
<p>There are two common implantable devices for the heart: <a href="https://www.nhlbi.nih.gov/health/pacemakers">artificial pacemakers</a> and <a href="https://www.nhlbi.nih.gov/health/defibrillators">defibrillators</a>. Artificial pacemakers keep blood and oxygen flowing during times of stress. Defibrillators are devices that detect dangerously fast heart rates and deliver shocks like those used during cardiopulmonary resuscitation, also known as CPR, to restart the heart.</p>
<p>Understanding how these devices work requires appreciating how the heart’s electrical system works and the weak links that cause malfunctions.</p>
<h2>The heart’s natural pacemaker system</h2>
<p>Abnormally slow heart rates result from breakdowns in two principal areas of the heart. </p>
<p>First, the <a href="https://www.ncbi.nlm.nih.gov/books/NBK459238/">sinoatrial, or SA, node</a> sets your “resting” heart rate, usually somewhere between 60 and 100 beats per minute. This is the base effort needed to circulate enough blood to sustain normal bodily function. Elevated levels of certain hormones circulating in the body, such as adrenaline and serotonin, can <a href="https://doi.org/10.3389/fphys.2020.00170">increase heart rate above resting levels</a>. </p>
<p>Trained athletes frequently have a lower resting heart rate due to extra physical conditioning. Like any other muscle, the heart becomes stronger with training. Because their heart functions more efficiently, athletes <a href="http://dx.doi.org/10.1136/heart.89.12.1455">require fewer heart beats overall</a> to circulate blood. </p>
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<a href="https://images.theconversation.com/files/564020/original/file-20231206-25-3nscgh.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Diagram of cross-section of heart showing the SA and AV nodes" src="https://images.theconversation.com/files/564020/original/file-20231206-25-3nscgh.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/564020/original/file-20231206-25-3nscgh.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=541&fit=crop&dpr=1 600w, https://images.theconversation.com/files/564020/original/file-20231206-25-3nscgh.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=541&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/564020/original/file-20231206-25-3nscgh.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=541&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/564020/original/file-20231206-25-3nscgh.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=680&fit=crop&dpr=1 754w, https://images.theconversation.com/files/564020/original/file-20231206-25-3nscgh.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=680&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/564020/original/file-20231206-25-3nscgh.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=680&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">Breakdowns in the sinoatrial and atrioventricular nodes can cause heart rate problems.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Conduction_system_en_(CardioNetworks_ECGpedia).png">Rob Kreuger, medical illustrator/Wikimedia Commons</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<p>The <a href="https://www.ncbi.nlm.nih.gov/books/NBK557664/">atrioventricular, or AV, node</a> is the second key area of the heart’s electrical wiring. The atrioventricular node takes information about how fast the heart is beating from the sinoatrial node and relays it to the ventricles, the muscular portions of the heart that allow it to pump blood to the rest of the body. </p>
<p>When the atrioventricular node breaks down, the ventricles don’t receive the electrical signal from the sinoatrial node instructing them to “pump,” or create a heartbeat. This causes heart rate to become dangerously slow. </p>
<h2>When heart rate is too slow</h2>
<p>If resting heart rate is abnormally low or fails to increase with hormonal changes, pacemakers can help keep blood and oxygen circulating at a healthy rate. </p>
<p>Both the SA node and the AV node <a href="https://doi.org/10.1146%2Fannurev-physiol-021119-034453">naturally slow with age</a>, but sometimes this happens at an accelerated pace and leads to abnormally slow heart rates. Slow heart rates can also be caused by other diseases, including <a href="https://www.thyroid.org/patient-thyroid-information/ct-for-patients/february-2020/vol-13-issue-2-p-3-4/">thyroid problems</a> and <a href="https://theconversation.com/lyme-carditis-things-can-get-complicated-when-lyme-disease-affects-heart-function-167045">Lyme disease</a>. In these cases, slow rates are treatable without a pacemaker.</p>
<p>A common <a href="https://www.nhlbi.nih.gov/health/pacemakers/how-it-works">pacemaker system</a> has a battery and two wires that can send and receive electrical signals. One wire rests near the sinoatrial node, and the second in one of the heart’s ventricles. </p>
<p>If the wire near the sinoatrial node doesn’t detect any electrical activity over a set time, the pacemaker’s battery will send an impulse to the ventricle to initiate an electrical signal. Within fractions of a second, the wire in the ventricle should detect that electrical activity. If an impulse is detected, this signifies that the AV node conducted the signal correctly to the rest of the heart, and the pacemaker does not activate. If the wire doesn’t receive this signal, the battery delivers an impulse through the wire directly to the ventricle, causing the muscle to contract and initiate a heartbeat.</p>
<p>The heart’s muscle will only contract in response to a pacemaker impulse if the muscle is otherwise healthy. Pacemakers <a href="https://scienceillustrated.com.au/blog/medicine/ask-us-will-pacemakers-still-work-after-death/">do not keep patients alive</a> if the heart shuts down, such as during a massive infection, blood clot or kidney failure. Pacemakers simply keep the heart rate in a comfortable range if the primary problem in the heart is electrical.</p>
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<a href="https://images.theconversation.com/files/564018/original/file-20231206-34417-smw7n5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Diagram of cross-section of heart with implanted pacemaker" src="https://images.theconversation.com/files/564018/original/file-20231206-34417-smw7n5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/564018/original/file-20231206-34417-smw7n5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=505&fit=crop&dpr=1 600w, https://images.theconversation.com/files/564018/original/file-20231206-34417-smw7n5.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=505&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/564018/original/file-20231206-34417-smw7n5.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=505&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/564018/original/file-20231206-34417-smw7n5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=635&fit=crop&dpr=1 754w, https://images.theconversation.com/files/564018/original/file-20231206-34417-smw7n5.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=635&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/564018/original/file-20231206-34417-smw7n5.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=635&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">Pacemaker electrodes are implanted directly in the heart.</span>
<span class="attribution"><a class="source" href="https://www.nhlbi.nih.gov/sites/default/files/inline-images/images_279.jpg">National Heart, Lung, and Blood Institute</a></span>
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<p>Doctors program a pacemaker’s software so the resting pulse doesn’t drop below a certain rate, commonly 50 to 60 beats per minute. If the resting rate is set at 60 beats per minute, the pacemaker will wait exactly one second before initiating an electrical pulse. The heart’s pulse rate can be higher than this number if the sinoatrial node initiates a heartbeat naturally. If the pacemaker detects activity from the sinoatrial node, it will reset its timer for another full second. </p>
<p>Modern pacemakers also contain sensors to predict whether the heart may benefit from a faster heart rate under certain circumstances. For example, pacemaker batteries <a href="https://doi.org/10.1111/jce.14733">contain accelerometers</a> like those used in pedometers to detect if a person is in motion. If these sensors activate, the pacemaker can raise its minimum rate like how the heart would normally respond to exercise. Sensors can also detect if a person begins to breathe more quickly or if the heart begins to contract more powerfully, all signs normally associated with increases in heart rate. </p>
<h2>When heart rate is too fast</h2>
<p>Like pacemakers, a <a href="https://www.nhlbi.nih.gov/health/defibrillators/how-do-defibrillators-work">cardiac defibrillator</a> comes with a battery and wires that record the heart’s rate. But instead of treating slow heart rates, defibrillators are programmed to detect fast heart rates, usually in the range of 200 beats per minute. Heart rates in this range are often caused by <a href="https://www.ncbi.nlm.nih.gov/books/NBK532954/">ventricular tachycardia</a> or <a href="https://www.ncbi.nlm.nih.gov/books/NBK537120/">ventricular fibrillation</a>, which are potentially lethal heart rhythms resulting from the lower chamber of the heart beating too quickly or quivering.</p>
<p>Certain people are at elevated risk for these types of rhythm disturbances. Many <a href="https://doi.org/10.1093/eurheartj/ehad015">cases of “sudden death”</a> in athletes and other young people are either suspected or proved to be related to ventricular fibrillation. </p>
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<figcaption><span class="caption">Defibrillators deliver an electric charge to restart the heart.</span></figcaption>
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<p>Defibrillators deliver internal shocks to the heart when their sensors detect either ventricular tachycardia or ventricular fibrillation. These shocks stop the heart for a fraction of a second to give the sinoatrial node a chance to resume its normal activity. These shocks <a href="https://abcnews.go.com/Health/HeartRhythmTreatment/story?id=5213935#">can be painful</a>, so doctors usually also prescribe medications or other procedures to help prevent needing the shocks in the first place. </p>
<p>A defibrillator is like a seatbelt: It is reassuring to have, but ideally it never needs to be deployed. </p>
<h2>Beyond the surgery</h2>
<p>Pacemakers and defibrillators do require some maintenance. Certain settings, such as how low the pacemaker will allow the pulse to go, <a href="https://doi.org/10.1111/j.1540-8159.2007.00968.x">can be adjusted over time</a>. Doctors have computers that can communicate with the devices and alter their programming. Some devices use Bluetooth technology. </p>
<p>The battery cannot be recharged and must be replaced, generally after six to 10 years. <a href="https://doi.org/10.1093/europace/eun359">Battery life</a> depends on how frequently the heart requires the pacemaker to initiate heartbeats. <a href="https://doi.org/10.5603/KP.2015.0147">Pacemaker wires</a> occasionally need to be replaced if they fracture or if the insulation wears down after years of bending with each heartbeat. On rare occasions, pacemaker parts are recalled. Usually these parts do not require replacement but <a href="https://doi.org/10.1007%2Fs12471-015-0669-6">may require special attention</a>. More frequent checkups of the electrical “health” of the devices are usually prescribed for early detection of any problems with battery life or wire failures.</p>
<p>Pacemakers and defibrillators are always changing, in part to keep up with medical and nonmedical technologies.</p>
<p>With cloud-based management systems that make medical information available to doctors in real time, <a href="https://theconversation.com/three-reasons-why-pacemakers-are-vulnerable-to-hacking-83362">security has become a major focus</a> of modern pacemaker software. Other medical technologies such as MRIs can change how pacemakers and defibrillators work if not handled carefully – MRIs create electromagnetic impulses that cardiac devices <a href="https://doi.org/10.1148/radiol.2018180285">can misinterpret as heartbeats</a>. Modern devices are engineered with these factors in mind, but still require careful programming for these special circumstances.</p>
<p>When used correctly, pacemakers and defibrillators improve both quality of life and life expectancy. While teams of engineers design these small machines, they rely on doctors knowing who will benefit from this technology and how to program the software to best serve each specific patient and scenario.</p><img src="https://counter.theconversation.com/content/217429/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Virginia Singla consults for Medtronic. </span></em></p>Heart rates that are too slow or too fast can sometimes be lethal. Medical implants can help the heart get its rhythm back.Virginia Singla, Clinical Assistant Professor of Cardiology, University of PittsburghLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2129192023-10-11T16:36:25Z2023-10-11T16:36:25ZIn praise of almonds and nuts<p>They’re known as <a href="https://www.em-consulte.com/article/79057/les-categories-d-aliments">‘oily fruits’</a>. Because of their numerous health benefits, notwithstanding their high fat content, almonds, hazelnuts and other nuts are among foods recommended for consumption in <a href="https://pubmed.ncbi.nlm.nih.gov/27712954/">Canada</a>, <a href="https://health.gov/our-work/food-nutrition/previous-dietary-guidelines/2015">the US</a>, <a href="https://www.santepubliquefrance.fr/determinants-de-sante/nutrition-et-activite-physique/documents/rapport-synthese/recommandations-relatives-a-l-alimentation-a-l-activite-physique-et-a-la-sedentarite-pour-les-adultes">France</a> and across <a href="https://ec.europa.eu/jrc/en/health-knowledge-gateway/promotion-prevention/nutrition/food-based-dietary-guidelines">the EU</a> – to the tune of a small handful each day.</p>
<p>From a nutritional standpoint, these hard-shelled fruits are <a href="https://www.elsevier-masson.fr/nutrition-clinique-pratique-9782294754685.html">distinguished</a> by high levels (50-75%) of unsaturated fats (which are seen as ‘good fats’), significant protein content (10-25%), plus minerals (sodium, magnesium, potassium), vitamins B3, B9, B6 and E, fibre, antioxidants and vegetable oils. A stack of data suggests that they could help us age well and protect us from a range of chronic conditions.</p>
<h2>Stripping out ‘bad’ cholesterol</h2>
<p>If there’s one area where shelled fruits <a href="https://mail.google.com/mail/u/0/"> [JN1]</a> have proved their worth, it’s bringing cholesterol down. Reducing the amount of animal fat in your diet and eating fibre are, for certain, effective ways to cut levels of LDL-cholesterol, that’s to say ‘bad cholesterol’. But many studies have also shown the benefits of a daily handful of almonds. The same seems true of all nuts.</p>
<p>In 2010, <a href="https://pubmed.ncbi.nlm.nih.gov/20458092/">a study of the collected data</a> over the course of 25 clinical trials involving men and women with high cholesterol showed that eating 67g of nuts every day for 3-8 weeks could cut LDL-C levels by 7.4%, with more sizeable effects than this on symptoms since the patients were over healthy limits previously.</p>
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<p>Another <a href="https://pubmed.ncbi.nlm.nih.gov/29931130/">systematic data review</a>confirmed this, albeit at a more modest rate. Carried out in 2018, it analysed results from 26 clinical trials: the authors in this case detected a 3.7% fall in LDL-C levels for a diet rich in shelled fruits (15-108g per day) over a period of one to 12 months. It’s known that lowering LDL-C levels is linked to <a href="https://pubmed.ncbi.nlm.nih.gov/29677301/">a reduction in total mortality and in deaths from cardiovascular disease</a>, particularly if levels were high to start with. Even if no clinical study has yet shown that eating nuts can reduce the risk of heart failure, there’s no shortage of arguments to support such a hypothesis.</p>
<h2>Lower risk of cardiovascular disease</h2>
<p>First one might point to the results of a <a href="https://pubmed.ncbi.nlm.nih.gov/31361320/">meta-analysis published in 2019</a>. Applying the criteria used by Canada’s Cochrane Centre, the authors chose 19 studies, and evaluated that a 28g daily portion of shelled fruits is associated with a 13% fall in cardiovascular disease, and 29% in deaths from heart disease.</p>
<p>You could also refer to a <a href="https://pubmed.ncbi.nlm.nih.gov/29897866/">huge randomised and controlled study across many different locations</a> on the role of a Mediterranean diet enriched with nuts in reducing the risk of heart disease. Participants in this, aged 55-80 and registering a significant risk of heart disease were assigned one of three diets – low-fat, a Mediterranean diet rich in olive oil, and a Mediterranean diet with added nuts. They were tracked for almost 5 years on average. At the end of the research, it was shown that heart problems were less frequent among the two groups following the Mediterranean diet.</p>
<h2>Fat that doesn’t make you put on weight</h2>
<p>On the energy side, 30g of almonds, peanuts, pistachios or cashews work out as a 180 calorie snack; the same quantity of pecans or Brazil nuts come to 220-230 calories. These figures are roughly equivalent to 30-40g of milk chocolate. Since the calorific content is essentially made up of fats, one might be given to think one must beware of ‘oily fruits’ if weight-watching. But that assumption would be wrong…</p>
<p>In fact, <a href="https://pubmed.ncbi.nlm.nih.gov/29977320/">a recent piece of research closely analysed</a> six cohort studies and 62 randomised diet tests. This concluded that regularly eating nuts for a longer or shorter period of time (between 3 and 336 weeks) is linked to very slight weight loss (an average of 200g) and a shrinking waistline (by an average of 0.5cm).</p>
<p>If the reasons for these counter-intuitive outcomes haven’t been adequately explained yet, various theories can be put forward. For one, the matrix that encases the oils in nuts limits, to an extent, their absorption in the gut. To put it simply – some of the fat content in nuts is eliminated in the body’s cells, rather than being absorbed. Meanwhile, thanks to how they blunt our appetite, almonds and other nuts reduce the amount we eat at meals, so much so that our overall calorie count is no greater, or perhaps less than it would have been without them.</p>
<h2>Do nuts have anti-cancer properties?</h2>
<p>Other benefits are attributed to shelled fruits – notably around cancer prevention, although the evidence for this is weak. The relevant studies rely on observations alone, and suffer from various interpretation biases.</p>
<p>Thus, according to <a href="https://pubmed.ncbi.nlm.nih.gov/32041895">an analysis of 33 studies published before June 2019</a>, increased consumption of nuts is demonstrably linked to a 10% fall in cancer risk; and the effect is more marked for cancers of the digestive system, with a risk reduction of 17%.</p>
<p>Nuts’ <a href="https://pubmed.ncbi.nlm.nih.gov/19703258">high antioxidant content</a> might be one of the drivers for this. But before exploring this hypothesis further, we need to check the observed data with verifiable controlled and randomised clinical trials. For the moment, there’s nothing that allows us to say that eating nuts protects against cancer.</p>
<h2>Fewer neurodegenerative conditions</h2>
<p>Oils and fats are vital for the brain. After fat tissue, it’s the organ in the body <a href="https://hal.archives-ouvertes.fr/hal-00897946/document">richest in lipids</a>: they can be found in the neuron membranes and related cells, but also in the myelin which speeds up the transmission of electrical impulses through the nervous system.</p>
<p>Several research teams have set out to evaluate the <a href="https://content.iospress.com/download/nutrition-and-aging/nua007?id=nutrition-and-aging%2Fnua007">benefits</a> of nuts for the central nervous system. What have they learned?</p>
<p>Their notable discovery was that <a href="https://pubmed.ncbi.nlm.nih.gov/18778529/">after a few weeks</a> of a diet more or less rich in nuts, 19 month-old rats performed better on psychometric tests. A diet of 2% nuts boosted their performance on a rod-clambering test, one of 6% nuts saw them do better on a plank-walking test, and at both these levels their powers of short term memory were heightened. <a href="https://pubmed.ncbi.nlm.nih.gov/22048906/">These results have been confirmed</a> by a study of shorter duration, with a marked improvement detectable in the rodents’ learning and memory.</p>
<p>As for humans, <a href="https://pubmed.ncbi.nlm.nih.gov/22349682/">a study of the PREDIMED diet intervention</a> has shown that a Mediterranean diet rich in nuts improves short-term memory. It has also offered evidence, at a biological level, of a <a href="https://pubmed.ncbi.nlm.nih.gov/22005283/">reduced risk of low BDNF plasma</a> – a protein which helps the growth and vigour of new neurons. Nuts seem to have a beneficial role at warding off age-related cognitive decline. However, we don’t have direct proof that if one regularly eats nuts, it reduces the risk of neurodegenerative diseases.</p>
<p>To sum up: nuts appear at first glance to have all the features allowing them to be considered allies of our health. While they are calorie-rich and high in fats, a 30g serving per day seems to cut “bad cholesterol” and protect us from cardiovascular disease, without affecting our weight. There are plenty of theories that suggest they a positive impact, both on other illnesses and warding off cognitive decline associated with age.</p>
<p>Plenty of good reasons to recommend everyone to include a handful of almonds, hazelnuts or other nuts in the food they eat each day – obviously without added sugar or salt!</p>
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<p><em>Translation from French into English by <a href="https://twitter.com/JoshNeicho">Joshua Neicho</a></em></p><img src="https://counter.theconversation.com/content/212919/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Les auteurs ne travaillent pas, ne conseillent pas, ne possèdent pas de parts, ne reçoivent pas de fonds d'une organisation qui pourrait tirer profit de cet article, et n'ont déclaré aucune autre affiliation que leur organisme de recherche.</span></em></p>Despite their high fat content, almonds, nuts and other shelled fruits do not make you put on weight. In fact, research continues to marvel over their seemingly endless health benefits.Boris Hansel, Médecin, Professeur des universités- Praticien hospitalier, Inserm U1148, Faculté de Santé, Université Paris CitéDiana Kadouch, Praticien Hospitalier, Hôpital Bichat, Service de Diabétologie-Nutrition, AP-HP, Chargée de cours au sein du DU de nutrition, Université Paris CitéJérémy Puyraimond-Zemmour, Assistant spécialiste, Service de Diabétologie-Nutrition, Hôpital Bichat, AP-HP, Chargé de cours au sein du DU de nutrition, Université Paris CitéLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2146892023-10-10T20:17:14Z2023-10-10T20:17:14ZMaking preventive care fair: New approaches like self-testing at home can save lives and promote health equity<figure><img src="https://images.theconversation.com/files/553014/original/file-20231010-19-axrszd.jpg?ixlib=rb-1.1.0&rect=6%2C121%2C4217%2C3262&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Justice in access to life-saving preventive care requires reaching out to those who need the most support.</span> <span class="attribution"><span class="source">(Shutterstock)</span></span></figcaption></figure><iframe style="width: 100%; height: 100px; border: none; position: relative; z-index: 1;" allowtransparency="" allow="clipboard-read; clipboard-write" src="https://narrations.ad-auris.com/widget/the-conversation-canada/making-preventive-care-fair-new-approaches-like-self-testing-at-home-can-save-lives-and-promote-health-equity" width="100%" height="400"></iframe>
<p>A fresh approach to preventive care is overdue to make health outcomes more fair. <a href="https://www.canada.ca/en/public-health/services/publications/science-research-data/key-health-inequalities-canada-national-portrait-executive-summary.html">Inequities based on racialization, income and gender mean that we need to urgently change the way care is provided</a>. Lives hang in the balance, especially for those who face barriers to care.</p>
<p>We worked with a national panel of colleagues and patients, all knowledgeable about health equity and many with lived experience of disadvantages, <a href="https://doi.org/10.1503/cmaj.230237">to develop guidance</a> on how to ensure everyone gets the preventive care they need, like cancer screening. It’s easy to bemoan inequities and idly suggest things should be different — our focus was on the specific actions that need to be taken.</p>
<h2>Home testing</h2>
<p>Outdated ways of providing care — like expecting patients to attend a clinic for a pelvic exam that is, at best, uncomfortable, and at worst, traumatizing, for cervical cancer screening — can lead to poor outcomes. In the case of cervical cancer screening, those outcomes can include delayed diagnosis of cervical cancer.</p>
<p><a href="https://doi.org/10.1001/jama.2018.10400">Self-testing for the virus that causes cervical cancer is at least as accurate</a> as the traditional approach of Pap tests that require a pelvic exam. Some patients avoid pelvic exams due to the inconvenience and discomfort, and survivors of sexual abuse might opt out of screening to avoid being re-traumatized. </p>
<p>The technology needed for self-testing has been <a href="https://www.cfp.ca/content/63/8/597?ijkey=fe09b8f3b9cb538fd1811755f762ff68d022894c&keytype2=tf_ipsecsha">around for years</a>. Studies have shown that it <a href="https://doi.org/10.1186/s12905-023-02174-w">helps connect people with care</a> in addition to being cost-effective. While the main benefit of self-testing is better access to screening for patients, avoiding visits also frees up physician time. </p>
<figure class="align-center ">
<img alt="A clinic waiting room with two women sitting in chairs and a person in scrubs approaching" src="https://images.theconversation.com/files/553015/original/file-20231010-15-278id.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/553015/original/file-20231010-15-278id.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/553015/original/file-20231010-15-278id.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/553015/original/file-20231010-15-278id.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/553015/original/file-20231010-15-278id.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/553015/original/file-20231010-15-278id.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/553015/original/file-20231010-15-278id.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=424&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">More equitable approaches, such as self-testing, can replace some outdated procedures that require clinic visits.</span>
<span class="attribution"><span class="source">(Shutterstock)</span></span>
</figcaption>
</figure>
<p>Skin testing for tuberculosis exposure — which requires an initial visit to implant the test in the forearm, and a return visit two or three days later to read the test — is another example of an old practice that can take a back seat to a more efficient approach. </p>
<p>Many people who have made two trips for a skin test might be surprised to learn there is a <a href="https://doi.org/10.1080/24745332.2022.2036503">blood test that is likely more accurate, especially for those who have been vaccinated</a>. The test is not expensive or new. It can be done today. But, like self-testing for cervical cancer, it needs to be publicly funded for everyone. </p>
<p>Self-testing for HIV can also remove the need for patients to attend an appointment and wait to receive a result. The answer can be <a href="https://maphealth.ca/hiv-oral-self-test/">available in minutes and with tests that are available from vending machines as part of a pilot program</a>. </p>
<p>With self-testing, there is also no need for patients to worry about being asked leading questions or being judged by a doctor when they request a test. Self-testing for HIV is an example of an innovation that can help both individuals and the population by reducing the spread of HIV. </p>
<h2>Better access to screening</h2>
<p><a href="https://canadiantaskforce.ca/guidelines/published-guidelines/depression/">Current guidelines</a> in Canada assume that people will receive periodic assessments of their mental health. But we know that many people <a href="https://doi.org/10.1503/cmaj.1096049">do not receive routine primary care</a>. We also know that income, as well as other social factors such as <a href="https://www.canada.ca/en/public-health/services/publications/science-research-data/key-health-inequalities-canada-national-portrait-executive-summary.html">racialization and gender identity, can determine access to care</a>, in part because some face discrimination within the health-care system. </p>
<p>For these reasons, we recommend routine screening for depression for people experiencing disadvantages.</p>
<figure class="align-center ">
<img alt="A woman in a white coat taking an older man's blood pressure" src="https://images.theconversation.com/files/553016/original/file-20231010-24-upls4u.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/553016/original/file-20231010-24-upls4u.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/553016/original/file-20231010-24-upls4u.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/553016/original/file-20231010-24-upls4u.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/553016/original/file-20231010-24-upls4u.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/553016/original/file-20231010-24-upls4u.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/553016/original/file-20231010-24-upls4u.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Blood pressure checks every three to five years — together with a comprehensive assessment of cardiovascular risk — can help ensure people have appropriate access to life-saving medicines that have helped to extend life expectancy.</span>
<span class="attribution"><span class="source">(Shutterstock)</span></span>
</figcaption>
</figure>
<p>Likewise, we suggest that people experiencing disadvantages be screened for colorectal cancer starting at age 45 years, while the <a href="https://canadiantaskforce.ca/guidelines/published-guidelines/colorectal-cancer/">recommendation for the general population is to start at age 50</a>. </p>
<p>Our recommendation for an earlier start is based on the fact that earlier screening <a href="https://doi.org/10.1001/jama.2021.6238">prevents deaths</a>, there are <a href="https://pubmed.ncbi.nlm.nih.gov/34128915/">disparities in cancer outcomes based on social factors</a>, and screening does not always start when patients are first notified. </p>
<p>High blood pressure is sometimes referred to as a “silent killer” because it usually causes no symptoms but it <a href="https://www.canada.ca/en/public-health/services/diseases/heart-health/high-blood-pressure.html">can result in a heart attack or a stroke</a>. We recommend blood pressure checks every three to five years — together with a comprehensive assessment of cardiovascular risk — to ensure people have appropriate access to life-saving medicines that have helped to extend life expectancy.</p>
<h2>Justice in access to care</h2>
<p>In an ideal world, guidance that prioritizes the health of those facing discrimination and disadvantages would not be needed. Life would be fair, care would be equitable and health outcomes would be level. But our world is not ideal. </p>
<p>We can actually achieve something better than “equal” treatment; we can achieve justice when it comes to access to life-saving preventive care by reaching out to those who need the most support.</p>
<p>One part of that is empowering patients and members of the public by informing them about the care they should be offered. You can visit <a href="https://www.screening.ca/">screening.ca</a> to be provided with a custom list of recommended interventions based on your age and answers to some yes-or-no questions.</p>
<p>Focusing on the needs of those who are treated unfairly could ultimately lead to improvements for everyone. Once the capacity of HPV testing is increased, self-testing will likely become a <a href="https://doi.org/10.1503/cmaj.211568">standard approach to cervical cancer screening, as it already has in Australia</a>. We could start with preventive care in redesigning health care for those who need it the most.</p>
<p>We also need to reflect on why the unfair status quo has persisted for so long. <a href="https://www.canada.ca/content/dam/phac-aspc/documents/services/publications/science-research/key-health-inequalities-canada-national-portrait-executive-summary/hir-full-report-eng.pdf">Governments</a> and large <a href="https://www.canada.ca/en/public-health/services/health-promotion/healthy-living/creating-a-healthier-canada-making-prevention-a-priority.html">health-care institutions</a> have all made grand statements about the need to tackle sexism, racism, ableism and other forms of discrimination. It is long past time for those institutions to fund and support specific actions to help those who have been disadvantaged by previous inaction.</p><img src="https://counter.theconversation.com/content/214689/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Nav Persaud receives funding from the Canadian Institutes of Health Research, the Canada Research Chairs program and the Ontario SPOR Support Unit. </span></em></p><p class="fine-print"><em><span>Aisha Lofters receives funding from the Canadian Institutes of Health Research, the Canadian Cancer Society, the Peter Gilgan Centre for Women's Cancers at Women's College Hospital, and Pfizer/ReThink Breast Cancer. </span></em></p>Cancer screening and other routine primary care can help address inequities if we choose to leave the unfair status quo behind.Nav Persaud, Canada Research Chair in Health Justice, University of TorontoAisha Lofters, Associate professor, Department of Family & Community Medicine, University of TorontoLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2107612023-09-19T12:20:32Z2023-09-19T12:20:32ZSpending time in space can harm the human body − but scientists are working to mitigate these risks before sending people to Mars<figure><img src="https://images.theconversation.com/files/545125/original/file-20230828-27-8wodoh.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C3649%2C2434&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">With NASA planning more missions to space in the future, scientists are studying how to mitigate health hazards that come with space flight. </span> <span class="attribution"><a class="source" href="https://newsroom.ap.org/detail/RocketLaunch/45d363b2268349d4a85f5c9f112757e1/photo?Query=space%20launch&mediaType=photo&sortBy=&dateRange=Anytime&totalCount=732&currentItemNo=12&vs=true">AP Photo/John Raoux</a></span></figcaption></figure><p>When <a href="https://www.space.com/record-17-people-in-earth-orbit-at-once">17 people</a> were in orbit around the Earth all at the same time on May 30, 2023, it set a record. With NASA and other federal space agencies planning more manned missions and commercial companies bringing people to space, opportunities for human space travel are rapidly expanding. </p>
<p>However, traveling to space poses risks to the human body. Since NASA wants to send a manned <a href="https://www.nasa.gov/topics/moon-to-mars">mission to Mars</a> in the 2030s, scientists need to find solutions for these hazards sooner rather than later.</p>
<p>As a kinesiologist who works with astronauts, I’ve spent years <a href="https://scholar.google.com/citations?user=KaVh79oAAAAJ&hl=en">studying the effects</a> space can have on the body and brain. I’m also involved in a NASA project that aims to <a href="https://www.nasa.gov/hrp/5-hazards-of-human-spaceflight">mitigate the health hazards</a> that participants of a future mission to Mars might face.</p>
<h2>Space radiation</h2>
<p>The Earth has a protective shield called a <a href="https://science.nasa.gov/heliophysics/focus-areas/magnetosphere-ionosphere">magnetosphere</a>, which is the area of space around a planet that is <a href="https://science.nasa.gov/heliophysics/focus-areas/magnetosphere-ionosphere">controlled by its magnetic field</a>. This shield filters out <a href="https://www.nrc.gov/reading-rm/basic-ref/glossary/cosmic-radiation.html">cosmic radiation</a>. However, astronauts traveling farther than the International Space Station will face continuous exposure to this radiation – equivalent to between <a href="https://www.nasa.gov/analogs/nsrl/why-space-radiation-matters">150 and 6,000 chest X-rays</a>.</p>
<p>This radiation can harm the <a href="https://doi.org/10.1080/26896583.2021.1891825">nervous and cardiovascular systems</a> including <a href="https://doi.org/10.1080/26896583.2021.1891825">heart and arteries</a>, leading to cardiovascular disease. In addition, it can <a href="https://doi.org/10.1080/26896583.2021.1885283">make the blood-brain barrier leak</a>. This can expose the brain to chemicals and proteins that are harmful to it – compounds that are safe in the blood but toxic to the brain.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/e9sN9gOEdG4?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">The blood-brain barrier keeps compounds flowing through your circulatory system out of your brain.</span></figcaption>
</figure>
<p>NASA is developing technology that can shield travelers on a Mars mission from radiation by building deflecting materials such as Kevlar and polyethylene into <a href="https://www.lockheedmartin.com/en-us/products/astrorad---what-you-wear-in-space-could-save-your-life.html">space vehicles and spacesuits</a>. Certain diets and supplements <a href="https://enterade.com/">such as enterade</a> may also minimize the effects of radiation. Supplements like this, also used in cancer patients on Earth during radiation therapy, can alleviate gastrointestinal side effects of radiation exposure.</p>
<h2>Gravitational changes</h2>
<p>Astronauts have to exercise in space to minimize the muscle loss they’ll face after a long mission. Missions that go as far as Mars will have to make sure <a href="https://www.nasa.gov/mission_pages/station/research/benefits/bone_loss.html">astronauts have supplements</a> such as <a href="https://my.clevelandclinic.org/health/treatments/24753-bisphosphonates">bisphosphonate</a>, which is used to prevent bone breakdown in osteoporosis. These supplements should keep their muscles and bones in good condition over long periods of time spent without the <a href="https://doi.org/10.1038/s41526-021-00158-4">effects of Earth’s gravity</a>. </p>
<p>Microgravity also affects the nervous and circulatory systems. On Earth, your heart pumps blood upward, and specialized valves in your circulatory system keep bodily fluids from pooling at your feet. In the absence of gravity, <a href="https://doi.org/10.3390/life4040621">fluids shift</a> toward the head.</p>
<p>My work and that of others has shown that this results in an expansion of fluid-filled spaces in the middle of the brain. Having extra fluid in the skull and no gravity to “hold the brain down” causes the <a href="https://doi.org/10.1016/j.neubiorev.2020.11.017">brain to sit higher in the skull</a>, compressing the top of the brain against the inside of the skull.</p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/545092/original/file-20230828-26-2dggpp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="A man wearing a white headset and a suit which has many wires coming out of it and a plastic panel connected to a laptop." src="https://images.theconversation.com/files/545092/original/file-20230828-26-2dggpp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/545092/original/file-20230828-26-2dggpp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=901&fit=crop&dpr=1 600w, https://images.theconversation.com/files/545092/original/file-20230828-26-2dggpp.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=901&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/545092/original/file-20230828-26-2dggpp.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=901&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/545092/original/file-20230828-26-2dggpp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1133&fit=crop&dpr=1 754w, https://images.theconversation.com/files/545092/original/file-20230828-26-2dggpp.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1133&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/545092/original/file-20230828-26-2dggpp.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1133&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">NASA astronaut Scott Kelly, pictured here, is wearing the Chibis lower body negative pressure suit, which may help counteract the negative effects of gravity-caused fluid shifts in the body.</span>
<span class="attribution"><a class="source" href="https://www.nasa.gov/mission_pages/station/research/news/b4h-3rd/hh-dressing-astronauts-for-return">NASA</a></span>
</figcaption>
</figure>
<p>These fluid shifts may contribute to <a href="https://doi.org/10.1038/s41526-020-0097-9">spaceflight associated neuro-ocular syndrome</a>, a condition experienced by many astronauts that affects the <a href="https://doi.org/10.1136/bjo-2022-322892">structure and function of the eyes</a>. The back of the eye can become flattened, and the nerves that carry visual information from the eye to the brain swell and bend. Astronauts can still see, though visual function may worsen for some. Though it hasn’t been well studied yet, <a href="https://doi.org/10.1038/s41526-020-0097-9">case studies suggest</a> this condition may persist even a few years after returning to Earth. </p>
<p>Scientists may be able to shift the fluids back toward the lower body using <a href="https://www.nasa.gov/mission_pages/station/research/news/b4h-3rd/hh-dressing-astronauts-for-return">specialized “pants</a>” that pull fluids back down toward the lower body like a vacuum. These pants could be used to redistribute the body’s fluids in a way that is more similar to what occurs on Earth.</p>
<h2>Mental health and isolation</h2>
<p>While space travel can damage the body, the isolating nature of space travel can also have <a href="https://www.doi.org/10.36131/cnfioritieditore20210502">profound effects on the mind</a>. </p>
<p>Imagine having to live and work with the same small group of people, without being able to see your family or friends for months on end. To learn to manage extreme environments and maintain communication and leadership dynamics, astronauts first undergo team training on Earth. </p>
<p>They spend weeks in either <a href="https://www.nasa.gov/mission_pages/NEEMO/index.html">NASA’s Extreme Environment Mission Operations</a> at the <a href="https://www.nasa.gov/mission_pages/NEEMO/facilities.html">Aquarius Research Station</a>, <a href="https://theconversation.com/how-nine-days-underwater-helps-scientists-understand-what-life-on-a-moon-base-will-be-like-121079">found underwater</a> off the Florida Keys, or mapping and exploring caves with the European Space Agency’s <a href="https://www.esa.int/Science_Exploration/Human_and_Robotic_Exploration/CAVES_and_Pangaea/What_is_CAVES">CAVES program</a>. These programs help astronauts build camaraderie with their teammates and learn how to manage stress and loneliness in a hostile, faraway environment.</p>
<p>Researchers are studying how to best monitor and support <a href="https://www.nasa.gov/feature/conquering-the-challenge-of-isolation-in-space-nasa-s-human-research-program-director">behavioral mental health</a> under these extreme and isolating conditions. </p>
<p>While space travel comes with stressors and the potential for loneliness, astronauts describe experiencing an <a href="https://doi.org/10.1037/cns0000086">overview effect</a>: a sense of awe and connectedness with all humankind. This often happens when viewing Earth from the International Space Station. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/545093/original/file-20230828-123419-a7cdj9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="The Earth, half-obscured by shadow, as seen hanging in darkness, from the Moon." src="https://images.theconversation.com/files/545093/original/file-20230828-123419-a7cdj9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/545093/original/file-20230828-123419-a7cdj9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/545093/original/file-20230828-123419-a7cdj9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/545093/original/file-20230828-123419-a7cdj9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/545093/original/file-20230828-123419-a7cdj9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/545093/original/file-20230828-123419-a7cdj9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/545093/original/file-20230828-123419-a7cdj9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Earthrise, a famous image taken during an Apollo mission, shows the Earth from space. While seeing the Earth from afar, many astronauts report feeling an awed ‘overview effect.’</span>
<span class="attribution"><a class="source" href="https://en.wikipedia.org/wiki/Earthrise#/media/File:NASA-Apollo8-Dec24-Earthrise.jpg">NASA</a></span>
</figcaption>
</figure>
<p>Learning how to support human health and physiology in space also has numerous <a href="https://technology.nasa.gov/">benefits for life on Earth</a>. For example, products that shield astronauts from space radiation and counter its harmful effects on our body can also treat cancer patients receiving radiation treatments. </p>
<p>Understanding how to protect our bones and muscles in microgravity could improve how doctors treat the frailty that often accompanies aging. And space exploration has led to many technological achievements advancing <a href="https://www.nasa.gov/mission_pages/station/research/benefits/water_purification.html">water purification</a> and <a href="https://theconversation.com/landsat-turns-50-how-satellites-revolutionized-the-way-we-see-and-protect-the-natural-world-186986">satellite systems</a>. </p>
<p>Researchers like me who study ways to preserve astronaut health expect our work will benefit people both in space and here at home.</p><img src="https://counter.theconversation.com/content/210761/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Rachael Seidler receives funding from the National Aeronautics and Space Administration, the Translational Research Institue for Space Health, the National Science Foundation, the National Institutes of Health, and the Office of Naval Research.</span></em></p>Space can damage everything from your cardiovascular and nervous systems to your mental health – long voyages can feel isolating for many.Rachael Seidler, Professor of Applied Physiology & Kinesiology, University of FloridaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2117482023-09-15T00:56:34Z2023-09-15T00:56:34ZHow can I lower my cholesterol? Do supplements work? How about psyllium or probiotics?<figure><img src="https://images.theconversation.com/files/545897/original/file-20230901-17-zovk4b.jpg?ixlib=rb-1.1.0&rect=2%2C0%2C1908%2C1279&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://www.pexels.com/photo/white-ceramic-bowls-with-supplements-7615572/">Nataliya Vaitkevich/Pexels</a></span></figcaption></figure><p>Your GP says you have high cholesterol. You’ve six months to work on your diet to see if that’ll bring down your levels, then you’ll review your options. </p>
<p>Could taking supplements over this time help?</p>
<p>You can’t rely on supplements alone to control your cholesterol. But there’s some good evidence that taking particular supplements, while also eating a healthy diet, can make a difference.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/got-high-cholesterol-here-are-five-foods-to-eat-and-avoid-63941">Got high cholesterol? Here are five foods to eat and avoid</a>
</strong>
</em>
</p>
<hr>
<h2>Why are we so worried about cholesterol?</h2>
<p>There are two main types of cholesterol, both affecting your risk of heart disease and stroke. Both types are carried in the bloodstream inside molecules called lipoproteins.</p>
<p><strong>Low-density lipoprotein or LDL cholesterol</strong></p>
<p>This is often called “bad” cholesterol. This lipoprotein carries cholesterol from the liver to cells throughout the body. High levels of LDL cholesterol in the blood can lead to the <a href="https://www.ahajournals.org/doi/full/10.1161/JAHA.118.011433">build-up of plaque</a> in arteries, which leads to an <em>increased</em> risk of heart disease and stroke. </p>
<p><strong>High-density lipoprotein or HDL cholesterol</strong></p>
<p>This is often called “good” cholesterol. This lipoprotein helps remove excess cholesterol from the bloodstream and transports it back to the liver for processing and excretion. Higher levels of HDL cholesterol are <a href="https://www.ahajournals.org/doi/full/10.1161/CIRCRESAHA.119.312617">linked to</a> a <em>reduced</em> risk of heart disease and stroke. </p>
<p>Diet can play a key role in reducing blood cholesterol levels, especially LDL (“bad”) cholesterol. Healthy dietary choices are <a href="https://theconversation.com/got-high-cholesterol-here-are-five-foods-to-eat-and-avoid-63941">well recognised</a>. These include a focus on eating more unsaturated (“healthy”) fat (such as from olive oil or avocado), and eating less saturated (“unhealthy”) fat (such as animal fats) and trans fats (found in some shop-bought biscuits, pies and pizza bases).</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/546536/original/file-20230905-26-5plf10.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Cut avocado, glass of olive oil, green herbs and cut lemon on timber background" src="https://images.theconversation.com/files/546536/original/file-20230905-26-5plf10.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/546536/original/file-20230905-26-5plf10.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/546536/original/file-20230905-26-5plf10.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/546536/original/file-20230905-26-5plf10.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/546536/original/file-20230905-26-5plf10.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/546536/original/file-20230905-26-5plf10.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/546536/original/file-20230905-26-5plf10.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">You can find unsaturated fat in foods such as olive oil and avocado.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/food-background-fresh-organic-avocado-lime-253287091">Shutterstock</a></span>
</figcaption>
</figure>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/health-check-whats-healthier-butter-or-margarine-19777">Health Check: what's healthier, butter or margarine?</a>
</strong>
</em>
</p>
<hr>
<h2>Fibre is your friend</h2>
<p>An additional way to significantly reduce your total cholesterol and LDL cholesterol levels through diet is by eating more <a href="https://theconversation.com/fiber-is-your-bodys-natural-guide-to-weight-management-rather-than-cutting-carbs-out-of-your-diet-eat-them-in-their-original-fiber-packaging-instead-205159">soluble fibre</a>.</p>
<p>This is a type of fibre that dissolves in water to form a gel-like substance in your gut. The gel can bind to cholesterol molecules preventing them from being absorbed into the bloodstream and allows them to be eliminated from the body through your faeces. </p>
<p>You can find soluble fibre in whole foods such as fruits, vegetables, oats, barley, beans and lentils.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/fiber-is-your-bodys-natural-guide-to-weight-management-rather-than-cutting-carbs-out-of-your-diet-eat-them-in-their-original-fiber-packaging-instead-205159">Fiber is your body's natural guide to weight management – rather than cutting carbs out of your diet, eat them in their original fiber packaging instead</a>
</strong>
</em>
</p>
<hr>
<h2>Fibre supplements, such as psyllium</h2>
<p>There are also many fibre supplements and food-based products on the market that may help lower cholesterol. These include:</p>
<ul>
<li><p><strong>natural soluble fibres</strong>, such as inulin (for example, Benefiber) or psyllium (for example, Metamucil) or beta-glucan (for example, in ground oats)</p></li>
<li><p><strong>synthetic soluble fibres</strong>, such as polydextrose (for example, STA-LITE), wheat dextrin (also found in Benefiber) or methylcellulose (such as Citrucel)</p></li>
<li><p><strong>natural insoluble fibres</strong>, which bulk out your faeces, such as flax seeds.</p></li>
</ul>
<p>Most of these supplements come as fibres you add to food or dissolve in water or drinks. </p>
<p>Psyllium is the fibre supplement with the strongest evidence to support its use in improving cholesterol levels. It’s been <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5413815/">studied</a> in at least 24 high-quality randomised controlled trials.</p>
<p>These trials show consuming about 10g of psyllium a day (1 tablespoon), as part of a healthy diet, <a href="https://www.sciencedirect.com/science/article/pii/S0002916523070107#:%7E:text=Conclusions%3A,mild%2Dto%2Dmoderate%20hypercholesterolemia.">can significantly lower</a> total cholesterol levels by 4% and LDL cholesterol levels by 7%.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/545910/original/file-20230901-20-orbx53.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Person stirring in psyllium into glass of water, bowl of psyllium next to glass" src="https://images.theconversation.com/files/545910/original/file-20230901-20-orbx53.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/545910/original/file-20230901-20-orbx53.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/545910/original/file-20230901-20-orbx53.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/545910/original/file-20230901-20-orbx53.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/545910/original/file-20230901-20-orbx53.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/545910/original/file-20230901-20-orbx53.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/545910/original/file-20230901-20-orbx53.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">You can mix psyllium fibre into a drink or add it to your food.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/woman-adds-spoon-psyllium-fiber-mix-2031428417">Shutterstock</a></span>
</figcaption>
</figure>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/health-check-are-you-eating-the-right-sorts-of-fibre-20089">Health Check: are you eating the right sorts of fibre?</a>
</strong>
</em>
</p>
<hr>
<h2>Probiotics</h2>
<p>Other cholesterol-lowering supplements, such as probiotics, are not based on fibre. Probiotics are thought to help lower cholesterol levels via a <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3352670/">number of mechanisms</a>. These include helping to incorporate cholesterol into cells, and adjusting the microbiome of the gut to favour elimination of cholesterol via the faeces.</p>
<p>Using probiotics to reduce cholesterol is an upcoming area of interest and the <a href="https://www.sciencedirect.com/science/article/abs/pii/S089990071500461X">research</a> is promising. </p>
<p>In a <a href="https://pubmed.ncbi.nlm.nih.gov/29384846/">2018 study</a>, researchers pooled results from 32 studies and analysed them altogether in a type of study known as a meta-analysis. The people who took probiotics reduced their total cholesterol level by 13%.</p>
<p><a href="https://www.tandfonline.com/doi/full/10.3109/07853890.2015.1071872">Other</a> <a href="https://link.springer.com/article/10.1007/s11906-020-01080-y">systematic reviews</a> support these findings.</p>
<p>Most of these studies use probiotics containing <em>Lactobacillus acidophilus</em> and <em>Bifidobacterium lactis</em>, which come in capsules or powders and are consumed daily.</p>
<p>Ultimately, probiotics could be worth a try. However, the effects will likely vary according to the probiotic strains used, whether you take the probiotic each day as indicated, as well as your health status and your diet.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/health-check-should-healthy-people-take-probiotic-supplements-95861">Health Check: should healthy people take probiotic supplements?</a>
</strong>
</em>
</p>
<hr>
<h2>Red yeast rice</h2>
<p><a href="https://www.nccih.nih.gov/health/red-yeast-rice">Red yeast rice</a> is another non-fibre supplement that has gained attention for lowering cholesterol. It is often used in Asia and some European countries as a complementary therapy. It comes in capsule form and is thought to mimic the role of the cholesterol-lowering medications known as statins.</p>
<p>A <a href="https://www.frontiersin.org/articles/10.3389/fphar.2021.819482/full">2022 systematic review</a> analysed data from 15 randomised controlled trials. It found taking red yeast rice supplements (200-4,800mg a day) was more effective for lowering blood fats known as triglycerides but less effective at lowering total cholesterol compared with statins.</p>
<p>However, these trials don’t tell us if red yeast rice works and is safe in the long term. The authors also said only one study in the review was registered in a major <a href="https://www.clinicaltrials.gov">database</a> of clinical trials. So we don’t know if the evidence base was complete or biased to only publish studies with positive results.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/546589/original/file-20230906-23-a4o8yh.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Red yeast rice capsules" src="https://images.theconversation.com/files/546589/original/file-20230906-23-a4o8yh.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/546589/original/file-20230906-23-a4o8yh.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=274&fit=crop&dpr=1 600w, https://images.theconversation.com/files/546589/original/file-20230906-23-a4o8yh.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=274&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/546589/original/file-20230906-23-a4o8yh.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=274&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/546589/original/file-20230906-23-a4o8yh.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=344&fit=crop&dpr=1 754w, https://images.theconversation.com/files/546589/original/file-20230906-23-a4o8yh.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=344&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/546589/original/file-20230906-23-a4o8yh.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=344&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Red yeast rice is often used in Asia and some European countries to lower cholesterol.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/red-yeast-rice-supplement-capsules-on-1625852824">Shutterstock</a></span>
</figcaption>
</figure>
<h2>Diet and supplements may not be enough</h2>
<p>Always speak to your GP and dietitian about your plan to take supplements to lower your cholesterol.</p>
<p>But remember, dietary changes alone – with or without supplements – might not be enough to lower your cholesterol levels sufficiently. You still need to quit smoking, reduce stress, exercise regularly and get enough sleep. Genetics can also play a role.</p>
<p>Even then, depending on your cholesterol levels and other risk factors, you may still be recommended cholesterol-lowering medications, such as <a href="https://jamanetwork.com/journals/jama/fullarticle/2795522">statins</a>. Your GP will discuss your options at your six-month review.</p><img src="https://counter.theconversation.com/content/211748/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Lauren Ball works for The University of Queensland and receives funding from the National Health and Medical Research Council, Queensland Health, Mater Misericordia and the Royal Australian College of General Practitioners. She is a Director of Dietitians Australia, a Director of the Darling Downs and West Moreton Primary Health Network and an Associate Member of the Australian Academy of Health and Medical Sciences.</span></em></p><p class="fine-print"><em><span>Emily Burch works for Southern Cross University.</span></em></p>If you try supplements, you still need to eat a healthy diet, exercise, reduce your stress, quit smoking and get enough sleep. Even then, they may still not be enough.Lauren Ball, Professor of Community Health and Wellbeing, The University of QueenslandEmily Burch, Dietitian, Researcher & Lecturer, Southern Cross UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2120722023-08-29T12:25:50Z2023-08-29T12:25:50ZPrescriptions for fruits and vegetables can improve the health of people with diabetes and other ailments, new study finds<figure><img src="https://images.theconversation.com/files/544806/original/file-20230825-16121-jw13nf.jpg?ixlib=rb-1.1.0&rect=38%2C0%2C6430%2C5266&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">"Food is medicine" programs recognize the vital importance of fresh produce in a person's overall health. </span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/healthy-eating-exercising-weight-and-blood-pressure-royalty-free-image/1280587810?phrase=food+as+medicine&adppopup=true">fcafotodigital/E+ via Getty Images</a></span></figcaption></figure><p>The health of people with diabetes, hypertension and obesity improved when they could get free fruits and vegetables with a prescription from their doctors and other health professionals. </p>
<p>We found that these patients’ <a href="https://doi.org/10.1161/CIRCOUTCOMES.122.009520">blood sugar levels, blood pressure and weight improved</a> in our new study published in Circulation: Cardiovascular Quality and Outcomes.</p>
<p>The improvements we saw in clinical outcomes could have a meaningful impact on overall health. For example, systolic blood pressure, or blood pressure during heartbeats, decreased more than 8 millimeters of mercury, or mm Hg, while diastolic blood pressure, or blood pressure between heartbeats, decreased nearly 5 mm Hg. For context, this is about half the drop <a href="https://doi.org/10.1016/j.amjhyper.2005.01.011">gained through medications that lower blood pressure</a>.</p>
<p>Many U.S. health care providers have been experimenting with “<a href="https://doi.org/10.1136/bmj.m2482">food is medicine</a>” programs, which provide free, healthy food to patients – sometimes for a year or more. </p>
<p>This is the largest analysis to date of produce prescription programs, which are one variety of these efforts. They let patients with diet-related illnesses get apples, broccoli, berries, cucumbers and other kinds of fruits and vegetables for free. In Los Angeles, Boise, Houston, Minneapolis and other places where the programs we studied were located, participants selected the produce of their choice at grocery stores or farmers markets using electronic cards or vouchers. They typically received about US$65 per month for four to 10 months. </p>
<p>We pooled data from 22 U.S. produce prescription locations operated by <a href="https://www.wholesomewave.org/">Wholesome Wave</a>, a nonprofit that promotes access to affordable, healthy food. None of the pilots had previously been evaluated. All 4,000 participants either had, or were at risk for, poor cardiometabolic health and were recruited from clinics serving low-income neighborhoods.</p>
<p>Participants in these programs ate more fruits and vegetables. They were also one-third less likely to <a href="https://theconversation.com/what-is-food-insecurity-152746">experience food insecurity</a> – not having enough food to meet basic needs and lead a healthy life. </p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/Nj_xQer-b7c?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Wholesome Wave’s Fruit & Vegetable Prescription Program explained.</span></figcaption>
</figure>
<h2>Why it matters</h2>
<p>More than 300,000 Americans <a href="https://doi.org/10.1001/jama.2017.0947">die annually of cardiovascular disease and diabetes</a> cases tied to what they eat.</p>
<p>The people in the estimated <a href="https://www.ers.usda.gov/webdocs/publications/104656/err-309_summary.pdf?v=9300.6">13.5 million U.S. households</a> experiencing food insecurity are more likely than others to have <a href="https://doi.org/10.1007%2Fs13668-021-00364-2">cardiometabolic health problems</a>, such as diabetes or heart disease. They also have <a href="https://doi.org/10.1161/JAHA.119.014629">shorter life expectancy</a> and <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6426124/">higher medical costs</a>. </p>
<p>Most Americans, regardless of their income, <a href="https://doi.org/10.1001/jama.2016.7491">don’t follow a healthy diet</a>. However, research shows that <a href="https://doi.org/10.1001%2Fjama.2019.13771">lower-income Americans tend to eat food</a> that’s slightly worse for their health than those who can afford to spend more.</p>
<p>The <a href="https://health.gov/our-work/nutrition-physical-activity/white-house-conference-hunger-nutrition-and-health">2022 White House Conference on Hunger, Nutrition and Health</a> brought together experts who outlined a national strategy to eradicate food insecurity and reduce diet-related illnesses. It <a href="https://www.whitehouse.gov/wp-content/uploads/2022/09/White-House-National-Strategy-on-Hunger-Nutrition-and-Health-FINAL.pdf">ended with a strategy calling for</a>, among other things, more produce prescription programs.</p>
<p>The last White House conference on hunger and nutrition, which occurred over 50 years earlier, <a href="https://doi.org/10.1093%2Fcdn%2Fnzaa082">led to significant and lasting changes in U.S. food policies</a>. The National School Lunch Program expanded and the <a href="https://www.fns.usda.gov/wic/about-wic-how-wic-helps">Special Supplemental Nutrition Program for Women, Infants and Children</a>, known as WIC, was created. </p>
<p>Within a year of the latest conference, two government agencies – the <a href="https://www.hhs.gov/about/news/2023/04/26/hhs-announces-25-million-produce-prescription-programs-indian-country.html">Indian Health Service</a> and the <a href="https://www.va.gov/houston-health-care/news-releases/va-and-the-rockefeller-foundation-join-forces-to-increase-healthy-food-access-improve-health-outcomes-for-veterans/">Veterans Health Administration</a> – announced produce prescription pilots. Eight state Medicaid programs have <a href="https://www.axios.com/2023/03/16/medicaid-for-food-next-states">received or applied for federal waivers</a> that would allow Medicaid to pay for produce prescriptions <a href="https://www.statnews.com/2023/06/27/food-as-medicine-cms-guidelines-produce-prescription/">for up to six months</a> for some people. However, these programs remain unavailable to most Americans who might benefit.</p>
<figure>
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<figcaption><span class="caption">Dariush Mozaffarian of Tufts University discusses ‘food is medicine’ initiatives.</span></figcaption>
</figure>
<h2>What’s next</h2>
<p>We are evaluating “food is medicine” pilots funded by the <a href="https://www.mass.gov/info-details/massachusetts-delivery-system-reform-incentive-payment-program#flexible-services-">Flexible Services Program</a> in Massachusetts’ Medicaid program. We are also running a large, randomized controlled trial, in which one group of patients with cancer will get free home-delivered meals and another will receive standard care.</p>
<p><em>The <a href="https://theconversation.com/us/topics/research-brief-83231">Research Brief</a> is a short take on interesting academic work.</em></p><img src="https://counter.theconversation.com/content/212072/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Kurt Hager volunteers as a steering committee member for the National Produce Prescription Collaborative.</span></em></p><p class="fine-print"><em><span>Fang Fang Zhang receives funding from the Rockefeller Foundation and East Bay Community Foundation for this work. </span></em></p>When people taking part in 22 pilot programs across the US got free fruits and vegetables, their health improved.Kurt Hager, Instructor of Epidemiology, UMass Chan Medical SchoolFang Fang Zhang, Professor of Epidemiology, Tufts UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2097352023-08-08T21:47:06Z2023-08-08T21:47:06ZCan physical activity boost our resilience to rising temperatures?<figure><img src="https://images.theconversation.com/files/540843/original/file-20230802-25-wjb3ec.jpeg?ixlib=rb-1.1.0&rect=8%2C0%2C1905%2C1276&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The number of days of extreme heat is set to increase in the years ahead. An active lifestyle can help reduce the impact on your health. </span> <span class="attribution"><span class="source">(Shutterstock)</span></span></figcaption></figure><p>Climate change, a high prevalence of chronic diseases and alarming levels of physical inactivity are three of the central challenges we face in the 21st century. </p>
<p>The increased frequency, duration and intensity of heat waves is one of the undeniable signs that climate change is well underway. According to the various climate scenarios, by the end of the century <a href="https://www.nature.com/articles/nclimate3322">between half and three-quarters of the world’s population will be exposed to lethal heat for more than 20 days per year</a>. </p>
<p>The future impact of extreme heat events will depend on the extent of climate change, but also on our ability to adapt to it by becoming less sensitive and vulnerable to heat, and therefore more resilient. As researchers in physical activity science and environmental physiology, we are assessing how adopting an active lifestyle can make us better equipped to cope with rising global temperatures.</p>
<h2>How can the human body combat heat?</h2>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/532038/original/file-20230614-6008-evbd3c.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/532038/original/file-20230614-6008-evbd3c.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=401&fit=crop&dpr=1 600w, https://images.theconversation.com/files/532038/original/file-20230614-6008-evbd3c.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=401&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/532038/original/file-20230614-6008-evbd3c.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=401&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/532038/original/file-20230614-6008-evbd3c.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/532038/original/file-20230614-6008-evbd3c.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/532038/original/file-20230614-6008-evbd3c.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">A child enjoys water jets in Montréal during a heat wave.</span>
<span class="attribution"><span class="source">(Shutterstock)</span></span>
</figcaption>
</figure>
<p>When exposed to heat, <a href="https://journals.lww.com/acsm-essr/Fulltext/2019/04000/Regulation_of_Body_Temperature_by_Autonomic_and.9.aspx">the body deploys several responses to try to dissipate it</a>. The first is conscious and depends on behavioural decisions we make to minimize exposure, such as seeking a cool place, switching on a fan or reducing our physical activity. </p>
<p>Secondly, if these strategies are not sufficient, the brain activates physiological responses that are beyond our control; blood vessels in the skin dilate to increase the blood supply and sweat glands increase their activity to excrete more sweat. </p>
<p>So it’s not surprising that any factor that affects these responses can alter the body’s ability to react adequately to heat exposure.</p>
<h2>Who are the most vulnerable groups?</h2>
<p>Although heat affects us all, evidence shows that <a href="https://www.canada.ca/en/health-canada/services/climate-change-health/populations-risk.html">certain groups of people are more sensitive to it, which increases their vulnerability</a>. </p>
<p>A number of individual factors including age, pre-existing health problems such as cardiovascular disease and Type 2 diabetes, the use of certain medications (anticholinergic drugs, beta blockers, antidepressants and diuretics, among others), being overweight or obese, having low functional and cognitive abilities and low cardiorespiratory fitness <a href="https://www.sciencedirect.com/science/article/pii/S0140673621012083">are all associated with reduced heat tolerance and a greater risk of developing heat-related health problems</a>. This is reflected in public health figures since <a href="https://www.cmaj.ca/content/182/10/1053.short">these factors are associated with an increased risk of hospitalization or death during an extreme heat event</a>. </p>
<p>This finding can be explained by the fact that several of these conditions are associated with two physiological responses:</p>
<ul>
<li><p>reduced voluntary and autonomous heat dissipation capacities, which increase the stress imposed on the body;</p></li>
<li><p>reduced physiological potential, which reduces the body’s ability to cope.</p></li>
</ul>
<p>Together, these two conditions increase the likelihood that the stress placed on the body will reach and exceed the body’s physiological potential, increasing the risk of developing heat-related health problems.</p>
<h2>How can regular physical activity improve resilience to heat?</h2>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/541144/original/file-20230804-18285-t9qc82.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/541144/original/file-20230804-18285-t9qc82.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/541144/original/file-20230804-18285-t9qc82.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=342&fit=crop&dpr=1 600w, https://images.theconversation.com/files/541144/original/file-20230804-18285-t9qc82.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=342&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/541144/original/file-20230804-18285-t9qc82.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=342&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/541144/original/file-20230804-18285-t9qc82.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=430&fit=crop&dpr=1 754w, https://images.theconversation.com/files/541144/original/file-20230804-18285-t9qc82.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=430&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/541144/original/file-20230804-18285-t9qc82.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=430&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption"></span>
<span class="attribution"><span class="source">Created with BioRender.com</span></span>
</figcaption>
</figure>
<p>Interestingly, of the many risk factors for developing heat-related health problems, several can be avoided by adopting a healthy, active lifestyle. In fact, doing regular physical activity throughout one’s life could mean being better equipped to cope with rising global temperatures:</p>
<ol>
<li><p>By bringing about a number of physiological adaptations that increase heat dissipation capacity (increased sweat production) and the body’s physiological potential (increased cardiovascular reserve), thereby increasing heat tolerance and helping to meet the increased demands placed on the cardiovascular system during heat stress;</p></li>
<li><p>By limiting the decline in cardiorespiratory fitness and thermoregulatory functions associated with obesity, chronic disease and the use of certain medications. Regular physical activity can also help to limit cognitive and functional decline, enabling people to maintain their independence, an important protective factor against heat;</p></li>
<li><p>By slowing the decline in cardiovascular function and thermoregulatory functions inherent in aging;</p></li>
<li><p>By contributing to improved mental well-being, which could help people cope with the stress associated with extreme heat episodes.</p></li>
</ol>
<p>Physical activity could therefore make an important contribution to our ability to adapt to rising global temperatures, increasing our individual and community resilience.</p>
<p>However, it is important to note that a number of other risk factors are not directly modifiable by a healthy and active lifestyle, including certain mental health disorders, low socio-economic status and limited access to cool or air-conditioned places, among others. It is also well established that people who engage in intense to moderate physical activity during heat episodes are at greater risk of developing heat-related health problems (agricultural workers, construction workers, restaurant workers, etc.).</p>
<h2>Is the next generation sufficiently equipped to meet this challenge?</h2>
<p>In Canada, the <a href="https://www.canada.ca/en/public-health/services/childhood-obesity/childhood-obesity.html">prevalence of obesity among five- to 17-year-olds has almost tripled in the last 30 years</a>. Currently, <a href="https://www.canada.ca/en/public-health/services/reports-publications/health-promotion-chronic-disease-prevention-canada-research-policy-practice/vol-37-no-11-2017/adherence-24hour-movement-guidelines-10-17-year-old-canadians.html">more than nine out of 10 young people do not meet Canada’s 24-hour exercise guidelines</a>. The same is true worldwide. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/532039/original/file-20230614-18-xsmcof.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/532039/original/file-20230614-18-xsmcof.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/532039/original/file-20230614-18-xsmcof.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/532039/original/file-20230614-18-xsmcof.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/532039/original/file-20230614-18-xsmcof.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/532039/original/file-20230614-18-xsmcof.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/532039/original/file-20230614-18-xsmcof.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Younger generations are less active than those who came before them. They risk being more vulnerable to extreme heat.</span>
<span class="attribution"><span class="source">(Shutterstock)</span></span>
</figcaption>
</figure>
<p>In Québec, recent figures paint a picture that is more than alarming: a <a href="https://www.frontiersin.org/articles/10.3389/fpubh.2022.1056484/full">15 per cent decrease in cardiorespiratory capacity and a 30 per cent decrease in functional capacity in young people</a> compared with their elders who underwent the same tests in the 1980s. Worse still, the researchers observed that among 15- to 17-year-olds, <a href="https://www.frontiersin.org/articles/10.3389/fpubh.2022.1056484/full">six out of 10 boys and seven out of 10 girls have a cardiorespiratory capacity that will expose them to cardiometabolic health problems in the future</a>. </p>
<p>Such trends suggest that today’s young people may be less and less equipped to tolerate heat, while they will be increasingly exposed to it. From a public health point of view, this is alarming. Maintaining regular physical activity and adequate fitness throughout their lives could make young people <a href="https://www.tandfonline.com/doi/full/10.1080/23328940.2022.2102375">better equipped to meet these challenges</a>.</p><img src="https://counter.theconversation.com/content/209735/count.gif" alt="La Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Les auteurs ne travaillent pas, ne conseillent pas, ne possèdent pas de parts, ne reçoivent pas de fonds d'une organisation qui pourrait tirer profit de cet article, et n'ont déclaré aucune autre affiliation que leur organisme de recherche.</span></em></p>Many heat-related health problems can be avoided by adopting a healthy, active lifestyle. But the younger generation is less active than previous generations, and therefore more vulnerable.Thomas Deshayes, Chercheur postdoctoral en sciences de l'activité physique, Université de MontréalJulien Periard, Research professor, University of CanberraLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2062042023-07-25T20:04:48Z2023-07-25T20:04:48ZCan’t afford a gym membership or fitness class? 3 things to include in a DIY exercise program<figure><img src="https://images.theconversation.com/files/538415/original/file-20230720-21-9hekky.jpg?ixlib=rb-1.1.0&rect=175%2C434%2C4490%2C2676&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><a class="source" href="https://unsplash.com/photos/lrQPTQs7nQQ">Jonathan Borba/Unsplash</a></span></figcaption></figure><p>With the rising cost of living, gyms memberships and fitness classes are becoming increasingly unaffordable. But the good news is you can make <a href="https://pubmed.ncbi.nlm.nih.gov/28655559/">just as much progress at home</a>.</p>
<p>Cardiovascular endurance, muscle strength and flexibility are the <a href="https://www.acsm.org/docs/default-source/publications-files/acsms-exercise-testing-prescription.pdf?sfvrsn=111e9306_4">most important</a> components of fitness. And each can be trained with little or no equipment. Let’s look at why – and how – to fit them into your DIY exercise program. </p>
<h2>1. Cardiovascular endurance</h2>
<p>Cardiovascular endurance exercise (or “cardio”) forces the heart and lungs to increase the supply of oxygen to the working muscles. Heart disease is a <a href="https://www.who.int/news-room/fact-sheets/detail/the-top-10-causes-of-death">leading cause of death</a> and cardiovascular endurance exercise helps keep the heart healthy. </p>
<p>The best thing about cardio is you don’t need any fancy equipment to do it. Walking, jogging and running are great options, as are cycling, skipping rope and swimming.</p>
<figure class="align-center ">
<img alt="Older man skips rope" src="https://images.theconversation.com/files/539133/original/file-20230725-17-g2ab6q.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/539133/original/file-20230725-17-g2ab6q.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/539133/original/file-20230725-17-g2ab6q.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/539133/original/file-20230725-17-g2ab6q.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/539133/original/file-20230725-17-g2ab6q.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/539133/original/file-20230725-17-g2ab6q.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/539133/original/file-20230725-17-g2ab6q.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Skipping rope can be a cardio workout.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/senior-man-running-city-jumping-rope-1411700741">Shutterstock</a></span>
</figcaption>
</figure>
<p>There are two approaches to maximise cardiovascular endurance:</p>
<ul>
<li><p><a href="https://pubmed.ncbi.nlm.nih.gov/8897392/">high-intensity interval training</a> (HIIT) – short bouts of hard exercise (around 80% to 95% of your maximum heart rate) interspersed with lower intensity recovery periods (around 40% to 50% of your maximum heart rate)</p></li>
<li><p><a href="http://pubmed.ncbi.nlm.nih.gov/26664271/">low-intensity steady-state</a> (LISS) exercise – aerobic activity performed continuously at a low-to-moderate intensity (around 50% to 65% of your maximum heart rate) for an extended duration.</p></li>
</ul>
<p>Both are great options. While high-intensity interval training can be more time efficient, low-intensity steady-state training might be more enjoyable and easier to sustain long-term. </p>
<p>No matter what you choose, <a href="https://www.who.int/news-room/fact-sheets/detail/physical-activity">aim for</a> a minimum of 150 minutes of moderate-intensity or 75 minutes of vigorous-intensity cardiovascular exercise each week. For example, you could try 30 minutes, five days per week of low intensity cardio, or 25 minutes, three days per week of high-intensity activity, or a combination of the two. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/dont-have-time-to-exercise-heres-a-regimen-everyone-can-squeeze-in-111600">Don't have time to exercise? Here's a regimen everyone can squeeze in</a>
</strong>
</em>
</p>
<hr>
<p>How do you know if you’re exercising at the right intensity? </p>
<p>Smart watches that measure heart rate can help to monitor intensity. Or you can rely on the good old-fashioned <a href="https://pubmed.ncbi.nlm.nih.gov/25536539/">talk test</a>. During low-intensity activity, you should be able to speak in full sentences. Conversely, short phrases (initially) or single words (towards the end) should be all that’s manageable during high-intensity exercise. </p>
<h2>2. Muscle strength</h2>
<p>Next is muscle strength, which we train through resistance exercise. This is important for bone health, balance and metabolic health, especially as we age and our <a href="https://pubmed.ncbi.nlm.nih.gov/30276173/">muscle mass and strength declines</a>.</p>
<p>Aim for two days per week of whole-body resistance exercise performed at a moderate or <a href="https://www.who.int/news-room/fact-sheets/detail/physical-activity">greater intensity</a>. Try to build two weekly sessions that target the major muscle groups. This could include:</p>
<ul>
<li>squats – lower to the ground from standing by bending the hips, knees, and ankles while keeping the chest up tall before returning to standing by straightening the hips, knees and ankles</li>
</ul>
<figure class="align-center ">
<img alt="Man does a squat in his living room" src="https://images.theconversation.com/files/538417/original/file-20230720-27-ktr6ea.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/538417/original/file-20230720-27-ktr6ea.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/538417/original/file-20230720-27-ktr6ea.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/538417/original/file-20230720-27-ktr6ea.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/538417/original/file-20230720-27-ktr6ea.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/538417/original/file-20230720-27-ktr6ea.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/538417/original/file-20230720-27-ktr6ea.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=424&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">You don’t need any equipment for squats.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/muscular-athletic-fit-man-tshirt-shorts-1497529373">Shutterstock</a></span>
</figcaption>
</figure>
<ul>
<li><p><a href="https://www.physio-pedia.com/Hip_Hinge">hinges</a> – fold forward at the hips by pushing your bottom back to the wall behind you, keeping your back straight. A slight bend in the knees is fine but aim to keep your shins vertical </p></li>
<li><p><a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7196742/">push-ups</a> – if a full push-up is too difficult, you can place your hands on a raised surface such as a step or a chair</p></li>
<li><p>horizontal and vertical pull ups – using something like a portable chin up bar, which you can buy from sports supply stores</p></li>
<li><p>vertical pushes – pushing an object (or weight) vertically from the top of your chest to an overhead position.</p></li>
</ul>
<figure class="align-center ">
<img alt="Woman in wheelchair lifts weights" src="https://images.theconversation.com/files/539143/original/file-20230725-15-4euho7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/539143/original/file-20230725-15-4euho7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/539143/original/file-20230725-15-4euho7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/539143/original/file-20230725-15-4euho7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/539143/original/file-20230725-15-4euho7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/539143/original/file-20230725-15-4euho7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/539143/original/file-20230725-15-4euho7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Vertical pushes involve lifting a weight from chest to over your head.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/disabled-old-woman-wheelchair-raising-arm-1992294383">Shutterstock</a></span>
</figcaption>
</figure>
<p>Once you have selected your exercises, <a href="https://pubmed.ncbi.nlm.nih.gov/35873210/">perform</a> 2–3 sets of 8–12 repetitions at a moderate to greater intensity, with about 90 seconds rest between each set.</p>
<p>As you progress, continue to challenge your muscles by adding an extra set to each exercise, or including dumbbells, changing body position or wearing a backpack with weights. The goal should be to progress slightly each session.</p>
<p>However, if you have any underlying health conditions, disabilities, or are unsure how best to do this, see an exercise physiologist or physiotherapist.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/why-weightlifting-is-beneficial-before-and-after-the-menopause-204846">Why weightlifting is beneficial before and after the menopause</a>
</strong>
</em>
</p>
<hr>
<h2>3. Flexibility</h2>
<p>Improved flexibility can <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3273886/">increase your range of motion</a> and improve your ability to manage daily life. </p>
<p>While we don’t know the <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3273886/">best means of increasing flexibility</a>, the most basic and readily accessible is static <a href="https://www.topendsports.com/testing/flex.htm">stretching</a>. Here, we lengthen the muscle – for example, the hamstrings, until we feel a “stretching” sensation. Hold that position for 15–30 seconds. </p>
<figure class="align-center ">
<img alt="People stretch their arms" src="https://images.theconversation.com/files/539137/original/file-20230725-15-it5mvb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/539137/original/file-20230725-15-it5mvb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=401&fit=crop&dpr=1 600w, https://images.theconversation.com/files/539137/original/file-20230725-15-it5mvb.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=401&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/539137/original/file-20230725-15-it5mvb.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=401&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/539137/original/file-20230725-15-it5mvb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/539137/original/file-20230725-15-it5mvb.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/539137/original/file-20230725-15-it5mvb.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Stretching can increase your range of motion.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/close-hands-elderly-people-stretching-before-769325845">Shutterstock</a></span>
</figcaption>
</figure>
<p>While the precise intensity of this stretching sensation <a href="https://pubmed.ncbi.nlm.nih.gov/26347668/">remains elusive</a>, <a href="https://pubmed.ncbi.nlm.nih.gov/29506306/">around 5–10 minutes</a> per week per <a href="https://exrx.net/Lists/Directory">muscle group</a>, spread across five days, seems to provide the best results. </p>
<h2>How to stick with it?</h2>
<p>The best exercise is the one that gets done. So, whatever you choose, make sure you enjoy it. After all, it’s about creating an ongoing commitment to exercise that will deliver long-term health benefits. </p>
<p>It’s also important to ensure you’re ready to exercise, especially if you have any underlying health issues, have been previously inactive, or are unsure how to start. A <a href="https://www.ausactive.org.au/apss">pre-exercise screening</a> can help you to determine whether you should see a doctor or allied health professional before starting an exercise program and for guidance on the next steps. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/new-study-much-of-what-were-told-about-gym-exercises-and-resistance-training-is-from-studies-of-males-by-men-205753">New study: much of what we're told about gym exercises and resistance training is from studies of males, by men</a>
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</em>
</p>
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<img src="https://counter.theconversation.com/content/206204/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>The authors do not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.</span></em></p>With the rising cost of living, gyms and fitness classes are becoming unaffordable. But you can make just as much progress at home if you include these three components.Lewis Ingram, Lecturer in Physiotherapy, University of South AustraliaHunter Bennett, Lecturer in Exercise Science, University of South AustraliaSaravana Kumar, Professor in Allied Health and Health Services Research, University of South AustraliaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2100822023-07-20T11:03:24Z2023-07-20T11:03:24ZPeople who exercise only on the weekend have similar heart-health benefits as those who exercise throughout the week<p>Exercise is good for your overall health and your heart in particular. Guidelines recommend that we should be doing <a href="https://www.gov.uk/government/publications/physical-activity-applying-all-our-health/physical-activity-applying-all-our-health">150 minutes</a> of moderate-to-vigorous activity a week. But does it matter when you do this exercise? Should you spread it out in the week or does it lose some of the benefit if you cram it in at the weekend?</p>
<p>A <a href="https://jamanetwork.com/journals/jama/article-abstract/2807286">new study</a> analysing data from the UK Biobank has attempted to answer this very question. Around 90,000 healthy, middle-aged people wore wrist bands (accelerometers) that tracked their activity. It recorded their activity levels for a week with particular attention to moderate-to-vigorous activity (more on that later). </p>
<p>The researchers found that in the six years after the accelerometer assessment, people who did regular moderate-to-vigorous activity had less stroke, heart attack, heart failure and atrial fibrillation (an irregular heart rhythm) compared with sedentary people. </p>
<p>The novel finding of this study was that there was no difference in outcomes in people who did more than half of their activity at the weekend compared with those who spread it out across the week. It didn’t matter when it was done, moderate-vigorous physical activity was associated with improved heart health. </p>
<p>In the study, the authors called people who did most of their 150 minutes a week of moderate-to-vigorous activity over 1-2 days “weekend warriors”. This gives the impression of Lycra-clad cyclists riding up mountains or muddied middle-aged men playing a gruelling 90 minutes of football. </p>
<p>Over 37,000 people in the study met the definition of the “weekend warrior” so why aren’t the roads filled with cyclists and the parks filled with footballers? It certainly seems to contradict the epidemic of obesity and sedentary lifestyle that we hear so much about. </p>
<h2>Weekend warriors? Really?</h2>
<p>It may seem like semantics, but the definition of the “weekend warrior” is important. In this study, the threshold used for moderate-to-vigorous exercise was three “mets” (metabolic equivalent of task). The mets scale is used to measure physical activity. For example, washing the dishes is 2.5 mets, vacuuming is 3.3 mets and walking at 3mph is 3.5 mets. To put this into context, cycling at 15mph on the flat is 10 mets. </p>
<p>The threshold of three mets is rather unambitious and seems like something that many people would achieve in their everyday lives without a concerted effort to exercise. So perhaps when thinking of the people in this study instead of being called “weekend warriors” they should have been called “Saturday strollers” or “Sunday stretchers”. </p>
<p>The other point about this study is that these people were not sports people or athletes but rather normal middle-aged people doing their normal activities, some of which included exercise and some of which were normal activities measured on an accelerometer. </p>
<p>This context is important when thinking about how we can use these results to inform our patients. I would not want anyone to think that doing two and a half hours of vacuuming or strolling at the weekend is enough to stave off heart disease. It is the bare minimum level of exercise. To see real benefits, you are going to need to break a sweat. </p>
<figure class="align-center ">
<img alt="Older couple out for a run." src="https://images.theconversation.com/files/538353/original/file-20230719-27-6v48rs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/538353/original/file-20230719-27-6v48rs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/538353/original/file-20230719-27-6v48rs.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/538353/original/file-20230719-27-6v48rs.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/538353/original/file-20230719-27-6v48rs.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/538353/original/file-20230719-27-6v48rs.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/538353/original/file-20230719-27-6v48rs.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">For maximum benefit, you have to break a sweat.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/active-retirement-senior-couple-running-exercising-105193535">Diego Cervo/Shutterstock</a></span>
</figcaption>
</figure>
<p>The relationship between exercise and heart health is simple: the more you exercise the greater the improvements in your health. This study did show that doing some physical activity is better for your heart than being sedentary, which is an important message for the many people not managing 150 minutes of moderate activity a week. </p>
<p>Knowing these limitations of this study, we should avoid the interpretation that it is OK to live a sedentary existence from Monday to Friday and then atone by doing an hour or so of strolling on a Saturday and Sunday. </p>
<p>The findings of this study do not support this interpretation. If 150 minutes without breaking a sweat is all you can manage, then it doesn’t matter when you do it. But if you can manage something more strenuous, then you really should make an effort to do it. </p>
<p>The findings of this study do not apply to more intense exercise, and if the opportunity comes to go for a bike to work on a Tuesday or go swimming on a Thursday, you should take it. Your heart will thank you.</p><img src="https://counter.theconversation.com/content/210082/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Peter Swoboda receives funding from the British Heart Foundation and Heart Research UK. </span></em></p>New study looks at the benefit of ‘weekend-warrior’ pattern of exercise.Peter Swoboda, Senior Lecturer, Cardiology, University of LeedsLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2082022023-07-20T08:03:37Z2023-07-20T08:03:37ZWhat is atrial fibrillation, the heart condition US President Joe Biden lives with?<p>US President Joe Biden <a href="https://www.whitehouse.gov/wp-content/uploads/2023/02/Health-Summary-2.16.pdf">has</a> the heart condition atrial fibrillation. This increases his risk of having a stroke <a href="https://www.stroke.org.uk/what-is-stroke/are-you-at-risk-of-stroke/atrial-fibrillation">five-fold</a> and <a href="https://academic.oup.com/eurheartj/article/42/5/373/5899003?login=false">doubles</a> the risk of a heart attack or dementia.</p>
<p>More than <a href="https://journals.sagepub.com/doi/full/10.1177/1747493019897870?casa_token=xNrhAk_qBIQAAAAA%3A2DRaB1b1avVWKJFlBsKmEgRYXienljZDL4qhdajIGcOp4F4MwX9r_77vySuqdNS7pzHbY9RiZXuwkpw">37.5 million</a> people globally also have atrial fibrillation, but many don’t realise they have it. </p>
<p>For most, the condition has few symptoms and does not limit daily life. However, identifying it and treating it is the only way to reduce its serious health consequences.</p>
<p>Our research, <a href="https://heart.bmj.com/content/early/2023/07/03/heartjnl-2023-322602">just published</a> in the journal Heart, looks at the importance of managing blood pressure in reducing such risks.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/health-check-what-do-my-blood-pressure-numbers-mean-29212">Health Check: what do my blood pressure numbers mean?</a>
</strong>
</em>
</p>
<hr>
<h2>What is atrial fibrillation?</h2>
<p>Atrial fibrillation is when the heart <a href="https://www.heartfoundation.org.au/bundles/your-heart/atrial-fibrillation">beats irregularly</a>, sometimes fast, sometimes slow. It’s the <a href="https://journals.sagepub.com/doi/full/10.1177/1747493019897870?casa_token=xNrhAk_qBIQAAAAA%3A2DRaB1b1avVWKJFlBsKmEgRYXienljZDL4qhdajIGcOp4F4MwX9r_77vySuqdNS7pzHbY9RiZXuwkpw">most common</a> heart rhythm disorder and is more common as you get older. But some people develop it in their 30s and 40s.</p>
<p>The abnormal heart rhythm starts in the top chambers of the heart, meaning the heart does not propel the blood forward properly. This, and the erratic movements of these heart chambers, result in blood pooling, and occasionally clots.</p>
<p>The heart can go into atrial fibrillation for short periods of time, and then return to normal rhythm, or stay in this abnormal heart rhythm continuously.</p>
<figure>
<iframe width="440" height="260" src="https://www.youtube.com/embed/UOkseyF-wrA?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Here’s what happens if you have atrial fibrillation and your heart beats irregularly.</span></figcaption>
</figure>
<h2>How do I know if I have it?</h2>
<p>Some people have lots of symptoms, such as heart palpitations (a feeling of fluttering or pounding heart), breathlessness or even discomfort, and know exactly when they have gone into atrial fibrillation. Their symptoms can stop what they would normally do. But others have no symptoms and don’t know they have atrial fibrillation. We know very little about why some people have symptoms and others do not.</p>
<p>If you have symptoms, discuss these <a href="https://academic.oup.com/eurheartj/article/42/5/373/5899003?login=false">with your GP</a>. Your GP will ask about triggers for your symptoms, your general health and other risk factors, and will likely organise an <a href="https://www.heartfoundation.org.au/bundles/your-heart/medical-tests-for-heart-disease">electrocardiogram</a> (also called an ECG). This is a type of non-invasive test where 12 leads are attached to your chest to measure the electrical activity of the heart.</p>
<p>Generally, your GP will refer you to a cardiologist (heart specialist) or a hospital clinic if they suspect you have a heart rhythm problem, including atrial fibrillation, for further testing and treatment.</p>
<p>Some people say you can detect atrial fibrillation using <a href="https://theconversation.com/should-you-really-use-your-smartwatch-or-fitness-wearable-to-monitor-your-heart-194060">consumer wearables</a>, such as smartwatches. However, it’s not clear how accurate these are.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/536191/original/file-20230707-25-yl4bur.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Health worker with ECG trace in hand, man lying on hospital bed in background" src="https://images.theconversation.com/files/536191/original/file-20230707-25-yl4bur.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/536191/original/file-20230707-25-yl4bur.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=403&fit=crop&dpr=1 600w, https://images.theconversation.com/files/536191/original/file-20230707-25-yl4bur.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=403&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/536191/original/file-20230707-25-yl4bur.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=403&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/536191/original/file-20230707-25-yl4bur.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=507&fit=crop&dpr=1 754w, https://images.theconversation.com/files/536191/original/file-20230707-25-yl4bur.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=507&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/536191/original/file-20230707-25-yl4bur.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=507&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">An ECG measures the electrical activity of your heart.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/electrocardiogram-ecg-hand-clinic-cardiology-heart-566691763">Shutterstock</a></span>
</figcaption>
</figure>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/is-this-love-or-an-arrhythmia-your-heart-really-can-skip-a-beat-when-youre-in-love-176537">Is this love ... or an arrhythmia? Your heart really can skip a beat when you're in love</a>
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<hr>
<h2>What happens after you’re diagnosed?</h2>
<p>Once diagnosed with atrial fibrillation, you will be assessed for serious potential complications, such as an increased risk of stroke.</p>
<p>You’ll be advised to manage any risk factors that worsen atrial fibrillation and increase your risk of stroke. This includes cutting down on alcohol, managing your weight and doing more exercise.</p>
<p>Some people at higher risk of a stroke will be started on blood thinning medicines. Some people may also need to take medicines to control their heart rhythm or have a procedure called “ablation”. This is when wires are passed into the heart to identify and treat the electrical origin of the condition.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/what-should-my-heart-rate-be-and-what-affects-it-98945">What should my heart rate be and what affects it?</a>
</strong>
</em>
</p>
<hr>
<h2>How about high blood pressure?</h2>
<p>More than <a href="https://www.ahajournals.org/doi/10.1161/CIRCRESAHA.117.311402#:%7E:text=Hypertension%20ultimately%20increases%20the%20risk,%25%20to%2080%25%20of%20individuals">three in five</a> people with atrial fibrillation also have high blood pressure (hypertension). This is another major cause of stroke and heart attack. So managing blood pressure is very important.</p>
<p>In our <a href="https://heart.bmj.com/content/early/2023/07/03/heartjnl-2023-322602">new research</a>, we analysed data from the electronic medical records from about 34,000 Australian GP patients with both atrial fibrillation and hypertension. We found one-in-three had poorly controlled blood pressure. This places a group already at a high risk of stroke at an even greater risk.</p>
<p>When someone’s blood pressure is poorly controlled, this is usually because their medicines are not adequately bringing down their blood pressure. This could be because doctors are not increasing the number of different types of medicine when needed, or because patients cannot afford their medicines, or forget to take them.</p>
<p>We also found that people who visited the same GP regularly were more likely to have their blood pressure controlled, so were at lower risk of stroke.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/537245/original/file-20230713-15-lr4gwj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Female doctor checking blood pressure of older male" src="https://images.theconversation.com/files/537245/original/file-20230713-15-lr4gwj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/537245/original/file-20230713-15-lr4gwj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/537245/original/file-20230713-15-lr4gwj.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/537245/original/file-20230713-15-lr4gwj.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/537245/original/file-20230713-15-lr4gwj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/537245/original/file-20230713-15-lr4gwj.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/537245/original/file-20230713-15-lr4gwj.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Our research highlighted the importance of seeing the same GP regularly.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/young-woman-doctor-wearing-white-uniform-1805492158">Shutterstock</a></span>
</figcaption>
</figure>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/how-to-recognise-a-stroke-and-what-you-should-know-about-their-treatment-63651">How to recognise a stroke and what you should know about their treatment</a>
</strong>
</em>
</p>
<hr>
<h2>Why is this important?</h2>
<p>It is important people at the highest risk of stroke – such as those with both atrial fibrillation and high blood pressure – are receiving appropriate treatment to minimise their risk.</p>
<p>Strokes, heart attacks and dementia are still leading causes <a href="https://www.aihw.gov.au/reports/life-expectancy-death/deaths-in-australia/contents/leading-causes-of-death">of death</a> and <a href="https://www.aihw.gov.au/reports/burden-of-disease/australian-burden-of-disease-study-2022/contents/summary#">ill health</a> in Australia. Prevention is so much better than treating them when they develop.</p><img src="https://counter.theconversation.com/content/208202/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Ritu Trivedi is a recipient of the Commonwealth Government Research Training Program Stipend Scholarship to support her PhD studies.</span></em></p><p class="fine-print"><em><span>Clara Chow receives funding from National Health and Medical Research Council. Dr Chow is affiliated with the Cardiac Society of Australia and New Zealand. </span></em></p><p class="fine-print"><em><span>Liliana Laranjo receives funding from the National Health and Medical Research Council. </span></em></p>This common heart condition puts you at increased risk of having a stroke, especially if you also have high blood pressure. But our new research shows what you can do to lower your risk.Ritu Trivedi, PhD Student, University of SydneyClara Chow, Cardiologist at Westmead Hospital; Director of the Westmead Applied Research Centre, University of SydneyLiliana Laranjo, Senior Lecturer in Digital Health and Community and Primary Health Care Practice, University of SydneyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1983422023-06-20T09:33:09Z2023-06-20T09:33:09ZIs hot yoga good for you? Exploring the science behind the sweat<iframe id="noa-web-audio-player" style="border: none" src="https://embed-player.newsoveraudio.com/v4?key=x84olp&id=https://theconversation.com/is-hot-yoga-good-for-you-exploring-the-science-behind-the-sweat-198342&bgColor=F5F5F5&color=D8352A&playColor=D8352A" width="100%" height="110px"></iframe>
<p><a href="https://theconversation.com/yoga-isnt-timeless-its-changing-to-meet-contemporary-needs-97162">Hot yoga</a> also known as <a href="https://www.yoga-society.com/blogs/types-of-yoga/what-is-bikram-yoga">Bikram yoga</a> (more on that later) has <a href="https://www.cnet.com/health/fitness/benefits-of-hot-yoga/">gained significant popularity in recent years</a> as a fairly ferocious form of exercise. It combines yoga poses and breathing exercises and is practised in a heated studio – with room temperatures close to 40°C.</p>
<p>This style of yoga is designed to replicate the environmental conditions of India and is typically practised for around 90 minutes, leaving students (and teachers) dripping in sweat come the end of class.</p>
<p>Practising hot yoga challenges the mind and places additional physiological strain on the body. It makes you very sweaty and increases your heart rate, which can feel pretty intense. Indeed, hot yoga can lead to <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5433110/">dehydration and dizziness</a>, especially if it’s your first time and you don’t begin the class hydrated.</p>
<p>Designed to develop strength, flexibility and balance, hot yoga is believed to offer enhanced physical and <a href="https://journals.copmadrid.org/pi/art/pi2022a4">mental health benefits</a> – including improved levels of fitness and <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4609431/">reduced stress levels</a>. </p>
<p>But it can also feel uncomfortable – think sweat trickling into your eyes while doing a headstand – and hard going: with fast, dynamic sequences repeated numerous times. Then there are also those tricky balances and multiple lunges, all done at high temperatures, meaning that at times classes can feel pretty gruelling.</p>
<p>So are all these hot sweaty postures actually any good for you? Let’s take a look at the science. </p>
<h2>The origins of hot yoga</h2>
<p>Before we go into the evidence, a bit on the history. Originally known as “<a href="https://www.shape.com/fitness/workouts/things-you-need-know-about-bikram-yoga">Bikram yoga</a>”, named after its creator Bikram Choudhury, the traditional style of hot yoga was developed in the early 1970s. It involves a series of 26 fixed postures, carried out over 90 minutes while experiencing extreme heat stress. </p>
<p>In recent years many yoga studios have chosen to <a href="https://www.theguardian.com/tv-and-radio/2019/dec/03/he-made-a-fortune-from-his-trademarked-bikram-yoga-but-now-his-empire-is-in-tatters">rebrand</a> these classes as “hot yoga”, having changed from the original 26 fixed postures to be more flowing and individual and to include music (which Bikram classes don’t). </p>
<p>Another reason many yoga studios have chosen to <a href="https://www.huffingtonpost.co.uk/entry/bikram-choudhury-sexual-assault_n_5d4dc527e4b0fd2733f0286f">move away from the Bikram style</a> of yoga is that <a href="https://www.theguardian.com/lifeandstyle/2017/feb/18/bikram-hot-yoga-scandal-choudhury-what-he-wanted">multiple women</a> have <a href="https://www.independent.co.uk/life-style/bikram-choudhury-yoga-rape-sexual-abuse-netflix-documentary-who-a9210771.html">come forward</a> with <a href="https://www.vogue.in/culture-and-living/content/bikram-hot-yoga-controversy-bikram-choudhury-sexual-assault-netflix-documentary">accusations of sexual harassment</a> and <a href="https://www.theguardian.com/film/2019/nov/20/bikram-choudhury-yoga-founder-abuse-netflix-documentary">assault against Choudhury</a>. This has led to <a href="https://www.latimes.com/local/lanow/la-me-ln-bikram-yoga-lawsuit-20160126-story.html">legal action</a> and been the focus of a 2019 Netflix documentary: <a href="https://www.netflix.com/gb/title/80221584">Bikram: Yogi, Guru, Predator</a>.</p>
<p>Even before the <a href="https://www.refinery29.com/en-gb/2019/11/8874728/bikram-yoga-founder-scandal-new-netflix-documentary">Bikram scandal</a>, not everyone in the yoga community backed the idea of hot yoga. This is because traditional yoga practice involves a series of postures known as sun salutations, which are performed early in the morning (when it’s cooler), not during the midday heat. </p>
<h2>What the science says</h2>
<p>Although <a href="https://hfjc.library.ubc.ca/index.php/HFJC/article/view/220">comprehensive scientific reviews</a> are <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4609431/">still lacking</a>, some studies have indicated potential health benefits from hot yoga. Modified Bikram yoga performed regularly has been <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4609431/">associated with</a> increased aerobic fitness and improved cardiovascular function. </p>
<p>Hot yoga has <a href="https://journals.lww.com/nsca-jscr/Fulltext/2018/10000/Efficacy_of_Hot_Yoga_as_a_Heat_Stress_Technique.23.aspx">shown promise</a> in terms of <a href="https://www.liebertpub.com/doi/full/10.1089/acm.2012.0709">heart health</a>, by lowering “bad cholesterol” levels and <a href="https://pubmed.ncbi.nlm.nih.gov/24138995/">improving glucose tolerance</a>. Glucose intolerance may indicate an increased risk of metabolic conditions, such as diabetes.</p>
<p>It has <a href="https://journals.lww.com/nsca-jscr/fulltext/2013/03000/bikram_yoga_training_and_physical_fitness_in.35.aspx?casa_token=6VxlqbNhg6YAAAAA:Q1t8bes2-X1blvLrO0vMe7AdpxJyZ4xtU69WSWoLbTtwTb7kHur2Lv5XjeIsy7OIRntbCb5Le1ciqCsWq60MElzJaEqJWDQ">also been linked</a> to an increase in <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4609431/">strength</a>, <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7241641/">flexibility</a> <a href="https://scielo.isciii.es/pdf/inter/v31n2/1132-0559-inter-31-2-0067.pdf">and enhanced mental health</a>, including improved stress management and sleep quality.</p>
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<img alt="Women in hot yoga studio sweating." src="https://images.theconversation.com/files/531979/original/file-20230614-21-cbnbgo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/531979/original/file-20230614-21-cbnbgo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/531979/original/file-20230614-21-cbnbgo.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/531979/original/file-20230614-21-cbnbgo.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/531979/original/file-20230614-21-cbnbgo.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/531979/original/file-20230614-21-cbnbgo.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/531979/original/file-20230614-21-cbnbgo.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">Getting a sweat on for that mind-body connection.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/fitness-asian-female-group-doing-namaste-527129368">Southtownboy Studio/Shutterstock</a></span>
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<p>Yoga is classified as a “light-intensity exercise” by the <a href="http://www.alternative-therapies.com/openaccess/ATHM_20_4_pate.pdf">American College of Sports Medicine</a> but <a href="https://www.researchgate.net/profile/Rajasree-Nambron-2/publication/281017791_Unilateral_spontaneous_adrenal_hemorrhage_in_pregnancy/links/55d14c3a08ae6a881385ec32/Unilateral-spontaneous-adrenal-hemorrhage-in-pregnancy.pdf#page=6">studies</a> show that hot yoga sessions can result in high heart rates, increased core temperatures of 38˚C-40˚C and substantial sweat losses – <a href="https://pubmed.ncbi.nlm.nih.gov/33230967/">up to 1.5 litres per session</a> – making it a more <a href="https://cdnsciencepub.com/doi/abs/10.1139/apnm-2017-0495">intense exercise</a>.</p>
<p>When it comes to hot yoga classes, <a href="https://www.lboro.ac.uk/microsites/lds/EEC/ICEE/textsearch/13proceedings/Environmental%20Ergonomics%20XV_Proceedings%20for%20Webpage_V1.pdf#page=153">research</a> has also found that novices and experienced practitioners exhibit similarities in heart rate but can differ in sweat rate and core temperature changes. The more experienced you are, the more you sweat and the hotter you may get. This is likely because more experienced hot yogis will be better adapted to the heat and so able to push harder.</p>
<p>It’s often claimed that practising yoga in a heated environment may help with “<a href="https://www.yogajournal.com/practice/does-yoga-detox-your-body/">detoxification</a>” and the release of <a href="https://www.cbsnews.com/news/reality-check-yoga-does-not-release-toxins-from-the-body/">toxins from the body</a> due to excessive sweating. But this is rubbish – that’s what our kidneys are for. The reality is that those who practice hot yoga will probably lose more <a href="https://physoc.onlinelibrary.wiley.com/doi/full/10.14814/phy2.14647#:%7E:text=Abstract,cation%20of%20the%20extracellular%20fluid.">sodium</a> (or salt) and so are more likely to become dehydrated through increased sweat loss compared to yoga in cooler conditions. </p>
<p>Given this, hot yoga may be of benefit to those wishing to adapt to heat stress. For example, athletes preparing for elite sports such as <a href="https://pubmed.ncbi.nlm.nih.gov/29979281/">hockey</a> – if performed safely. </p>
<h2>And the risks?</h2>
<p>Because hot yoga can be physically demanding, <a href="https://www.hindawi.com/journals/ecam/2015/428427/">it may not be suitable for everyone</a>, especially for those with certain medical conditions or sensitivity to heat. Plus, some of the research looking at the benefits of hot yoga <a href="https://pubmed.ncbi.nlm.nih.gov/22592178/">hasn’t been replicated</a> – essentially meaning that further investigations are required to fully understand the true value of hot yoga in terms of physical fitness.</p>
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<iframe width="440" height="260" src="https://www.youtube.com/embed/796kNNslyLg?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
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<p>So while it does seem that there are some potential benefits, it’s important to be mindful of the potential risks associated with hot yoga, too. The heated environment, for example, can increase the risk of dehydration, heat exhaustion and potentially heat stroke, especially if <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5433110/">proper hydration practices</a> are not followed.</p>
<p>People with certain medical conditions, such as heart disease or high blood pressure, or those who are pregnant may need to exercise caution or consult their doctor before participating in hot yoga. And it’s vital that students listen to their bodies, take breaks when needed and stay hydrated throughout their practice.</p>
<p>With hot and humid conditions, on top of excessive sweating, hygiene and cleanliness is also important for you and your mat. So don’t forget your towel and wipe your mat down afterwards too.</p><img src="https://counter.theconversation.com/content/198342/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>The authors do not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Sweating it out can be beneficial for maintaining fitness and good mental health, but it’s not right for everyone.Ash Willmott, Senior Lecturer in Sport and Exercise Science, Anglia Ruskin UniversityJessica Mee, Senior Lecturer in Sport and Exercise Science, University of WorcesterLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2069682023-06-06T12:51:53Z2023-06-06T12:51:53ZWeighted vests: should you use them during exercise?<figure><img src="https://images.theconversation.com/files/530108/original/file-20230605-27-fk3adz.jpg?ixlib=rb-1.1.0&rect=12%2C6%2C4252%2C2837&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Weighted vests help boost the intensity of the exercise you're doing.</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/uzhgorod-ukraine-september-6-2020-athlete-1810216942">Yanosh Nemesh/ Shutterstock</a></span></figcaption></figure><p>Weighted vests have long been popular with athletes and celebrities such as David Beckham and former Hollyoaks star Gemma Atkinson. But interest in their use may have been piqued recently after Facebook founder Mark Zuckerberg shared a sweaty selfie of himself <a href="https://www.instagram.com/p/Cs1pltwPx1a/">wearing one</a> on Instagram.</p>
<p>Weighted vests usually weigh 5-20kg. They’re typically worn to increase exercise intensity. Some vests are a fixed weight and others contain pockets where different weight plates can be added before putting it on.</p>
<p>Historically, weighted vests have been used to train soldiers to carry heavy loads. These might include protective equipment that soldiers wear, such as <a href="https://academic.oup.com/milmed/article/175/9/664/4344622%22%22">bullet-proof vests</a>, which weigh around 10kg. In some countries, firefighters are also required to <a href="https://nationaltestingnetwork.com/publicsafetyjobs/cpat_info.cfm">train with weighted vests</a> to prepare them for the demands of their job.</p>
<p>More recently, people have been using weighted vests during workout challenges, as part of CrossFit or even while running, in the hope of boosting their fitness. And research backs their benefits.</p>
<p>For instance, <a href="https://www.tandfonline.com/doi/full/10.1080/00140139.2021.1961876">one study found</a> that runners who wore a weighted vest used more oxygen – a marker of fitness – than those who didn’t. </p>
<p>Participants were given a weighted vest (9kg for men and 6kg for women) and instructed to jog at half the intensity they were capable of. Alongside using more oxygen, the weighted vest group had a higher heart rate and burned more calories. The men who wore weighted vests while running also burned more carbohydrates. </p>
<p>These results mean that people who run with a weighted vest may get fitter quicker, and will probably <a href="https://www.sciencedirect.com/science/article/abs/pii/0026049594902593">burn more body fat in the long term</a>. However, you have to be fit to undertake these kinds of challenging workouts and see these types of results. </p>
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<img alt="A young man wearing a weighted vest runs along a beach." src="https://images.theconversation.com/files/530109/original/file-20230605-15-7t4hd2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/530109/original/file-20230605-15-7t4hd2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/530109/original/file-20230605-15-7t4hd2.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/530109/original/file-20230605-15-7t4hd2.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/530109/original/file-20230605-15-7t4hd2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/530109/original/file-20230605-15-7t4hd2.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/530109/original/file-20230605-15-7t4hd2.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">Weighted vests may be good for boosting cardiovascular fitness.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/young-bearded-athlete-training-outdoor-weighted-1432512671">Sergii Kovalov/ Shutterstock</a></span>
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<p>Weighted vests can also help to boost intensity during resistance training workouts. One study compared the effect of <a href="https://academic.oup.com/milmed/article/175/9/664/4344622">wearing a weighted vest</a> on participants who undertook a six-week military-style training programme. Participants completed various types of training, including running and calisthenics (a type of resistance training that uses bodyweight exercises to build strength).</p>
<p>The researchers found that the participants who wore the weighted vests showed a nearly 4% improvement in their performance on an uphill treadmill walk compared with the control group who didn’t wear a vest. They also had an almost 4% improvement in the amount of oxygen their body used during exercise. However, the improvements in calisthenics measures (performing push ups and sit-ups) were similar in both the group who wore vests and the group who didn’t. It’s not clear why there was little difference between the two groups. </p>
<p>Weighted vests are also beneficial during less intense workouts. One study found that when men wore a 9kg weighted vest while <a href="https://www.tandfonline.com/doi/full/10.1080/00140139.2021.1961876">walking uphill</a> for ten minutes, their heart rate increased by ten additional beats per minute – a sign their body was working harder. They also burned 6% more calories while wearing the weighted vest compared with when they weren’t wearing one.</p>
<p>So doing something as simple as wearing a weighted vest on your daily dog walk could have a big benefit to your physical health – including your cardiovascular health and metabolism. </p>
<p>While we still don’t have much evidence showing whether weighted vests themselves improve our ability to gain muscle, we do know that wearing them can have big benefits for cardiovascular health. We also don’t have much research on older participants – and what studies we do have have used lighter weights (1-5kg), which may <a href="https://pubmed.ncbi.nlm.nih.gov/10733058/#:%7E:text=Conclusions%3A%20Weighted%20vest%20use%20did,strength%20gains%20or%20bone%20stimulation.">have no effect</a>. It will be important for more research to be done which looks at how weighted vests may benefit many different groups of people.</p>
<h2>Potential risks</h2>
<p>It’s important to note that weighted vests may also come with certain risks. Some research in military personnel found that carrying heavy items on their back or torso carried an increased risk of <a href="https://link.springer.com/article/10.1007/s10926-014-9540-7">musculoskeletal injury</a>, particularly in the legs and the back. This could be because carrying weight increases the <a href="https://pubmed.ncbi.nlm.nih.gov/17337189/#:%7E:text=Increased%2520GRFs%252C%2520particularly%2520in%2520the,associated%2520with%2520military%2520load%2520carriage.">amount of force</a> that exists between the body and the ground – making it harder on the joints when moving. However, much of this research is on carrying loads over 25kg, often more than what is used for weighted vests.</p>
<p>Research also shows that <a href="https://ke.army.mil/bordeninstitute/other_pub/loadcarriagepdf.pdf">military personnel</a> who frequently carry a heavy load experience changes in their <a href="https://pubmed.ncbi.nlm.nih.gov/20496244/">walking and running gait</a>. Typically, this manifests as a shorter stride. These changes probably occur to compensate for carrying more weight – and may in turn increase the risk of injury.</p>
<p>But <a href="https://www.tandfonline.com/doi/full/10.1080/00140139.2021.1961876">my research</a> using weighted vests in CrossFit showed no changes in gait. This suggests that using a weighted vest occasionally during training may not necessarily increase your risk of leg, knee or ankle injury.</p>
<p>Most research suggests the heavier the load, the <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8069713/">greater the risk</a> of injury. This is because heavy loads make our <a href="https://link.springer.com/book/10.1007/978-3-319-33012-9">backs and torsos stiffer</a>, which can increase the risk of muscle and tendon strains.</p>
<p>As such, most people in good health who don’t have any existing injuries can probably safely use a weighted vest during their workouts. But to avoid the risk of injury, make sure you start with a light weight at first (around 2-3kg) and gradually increase the weight over several weeks as your body becomes accustomed to it. This will maximise the benefits that weighted vests afford while limiting the risk of injury from pushing too hard too soon.</p><img src="https://counter.theconversation.com/content/206968/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Christopher Gaffney does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Weighted vests have long been popular among CrossFit athletes and celebrities.Christopher Gaffney, Senior Lecturer in Integrative Physiology, Lancaster UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2025952023-05-05T12:14:19Z2023-05-05T12:14:19ZObesity in children is rising dramatically, and it comes with major – and sometimes lifelong – health consequences<figure><img src="https://images.theconversation.com/files/524166/original/file-20230503-24-l7rhni.jpg?ixlib=rb-1.1.0&rect=22%2C33%2C7326%2C4869&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Knowing how to talk to kids about healthful eating is key.</span> <span class="attribution"><a class="source" href="https://unsplash.com/photos/xtd3zYWxEs4">MI PHAM/Unsplash</a></span></figcaption></figure><p>In the past two decades, <a href="https://doi.org/10.1542/peds.2021-053708">children have become more obese</a> and have developed obesity at a younger age. A 2020 report found that <a href="https://www.cdc.gov/obesity/data/childhood.html#">14.7 million</a> children and adolescents in the U.S. live with obesity. </p>
<p>Because <a href="https://childhoodobesityfoundation.ca/what-is-childhood-obesity/complications-childhood-obesity/">obesity is a known risk factor</a> for <a href="https://www.mayoclinic.org/diseases-conditions/childhood-obesity/symptoms-causes/syc-20354827">serious health problems</a>, its <a href="https://www.cdc.gov/mmwr/volumes/70/wr/mm7037a3.htm">rapid increase during the COVID-19 pandemic</a> raised alarms.</p>
<p>Without intervention, many obese <a href="https://doi.org/10.1111/obr.12334">adolescents will remain obese</a> as adults. Even before adulthood, some children will have serious health problems beginning in their preteen years.</p>
<p>To address these issues, in early 2023, the American Academy of Pediatrics released its <a href="https://www.aap.org/en/news-room/news-releases/aap/2023/american-academy-of-pediatrics-issues-its-first-comprehensive-guideline-on-evaluating-treating-children-and-adolescents-with-obesity/">first new obesity management guidelines</a> in 15 years.</p>
<p>I am a <a href="https://www.scvmc.org/find-provider-result?field_specialties_target_id=536&field_spoken_language_target_id=All&title=&field_gender_target_id=All&sort_bef_combine=field_last_name_value_ASC">pediatric gastroenterologist</a> who sees children in the largest public hospital in California, and I have witnessed a clear trend over the last two decades. Early in my practice, I only occasionally saw a child with a complication of obesity; now I see multiple referrals each month. Some of these children have severe obesity and several health complications that require multiple specialists.</p>
<p>These observations prompted my reporting for the <a href="https://centerforhealthjournalism.org/2023/03/06/pandemic-made-childhood-obesity-even-worse-how-can-we-help-children-most-risk">California Health Equity Fellowship</a> at the University of Southern California. </p>
<p>It’s important to note that not all children who carry extra weight are unhealthy. But evidence supports that obesity, especially severe obesity, requires further assessment.</p>
<h2>How obesity is measured</h2>
<p>The <a href="https://www.who.int/health-topics/obesity#tab=tab_1">World Health Organization defines obesity</a> as “abnormal or excessive fat accumulation that presents a risk to health.” </p>
<p>Measuring fat composition requires specialized equipment that is not available in a regular doctor’s office. Therefore most clinicians use body measurements to screen for obesity. </p>
<p>One method is body mass index, or BMI, a calculation based on a child’s height and weight compared to age- and sex-matched peers. BMI doesn’t measure body fat, but when <a href="https://www.cdc.gov/healthyweight/assessing/bmi/index.html">BMI is high</a>, it correlates with total body fat.</p>
<p>According to the <a href="https://doi.org/10.1542/peds.2022-060640">American Academy of Pediatrics</a>, a child qualifies as overweight at a BMI between the <a href="https://www.cdc.gov/growthcharts/clinical_charts.htm">85th and 95th percentile</a>. Obese is defined as a <a href="https://www.cdc.gov/obesity/basics/childhood-defining.html">BMI above the 95th percentile</a>. Other screens for obesity include <a href="https://www.nccor.org/nccor-tools/a-guide-to-methods-for-assessing-childhood-obesity/">waist circumference and skin-fold thickness</a>, but these methods are less common. </p>
<p>Because many children exceeded the limits of existing growth charts, in 2022 the Centers for Disease Control and Prevention introduced <a href="https://www.cdc.gov/growthcharts/extended-bmi.htm">extended growth charts</a> for severe obesity. Severe obesity occurs when a child reaches the 120th percentile or has a BMI over 35. For instance, a 6-year-old boy who is 48 inches tall and is 110 pounds would meet criteria for severe obesity because his BMI is 139th percentile.</p>
<p><a href="https://doi.org/10.1161/cir.0b013e3182a5cfb3">Severe obesity</a> carries a heightened risk of liver disease, cardiovascular disease and metabolic problems such as diabetes. As of 2016, almost <a href="https://doi.org/10.1542%2Fpeds.2017-3459">8% of children ages 2 to 19 had severe obesity</a>.</p>
<p>Other health problems associated with severe obesity include <a href="https://doi.org/10.1155%2F2012%2F134202">obstructive sleep apnea</a>, <a href="https://orthoinfo.aaos.org/en/diseases--conditions/slipped-capital-femoral-epiphysis-scfe">bone and joint problems</a> that can cause early arthritis, <a href="https://doi.org/10.5527%2Fwjn.v4.i2.223">high blood pressure</a> and <a href="https://doi.org/10.1159/000492826">kidney disease</a>. Many of these problems occur together.</p>
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<iframe width="440" height="260" src="https://www.youtube.com/embed/ZpbZ33Dc53E?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">More and more children are developing diseases that have traditionally only been seen in adults.</span></figcaption>
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<h2>How obesity affects the liver</h2>
<p>The liver disease associated with obesity is called nonalcoholic <a href="https://www.niddk.nih.gov/health-information/liver-disease/nafld-nash-children#">fatty liver disease</a>. To store excess dietary fat and sugar, the liver’s cells fill with fat. Excess carbohydrates in particular get processed into substances similar to the <a href="https://doi.org/10.3945%2Fan.112.002998">breakdown products of alcohols</a>. Under the microscope, a pediatric fatty liver looks similar to a liver with alcohol damage.</p>
<p>Occasionally children with fatty liver are not obese; however, the <a href="https://doi.org/10.1002/cld.1027">greatest risk factor for fatty liver</a> is obesity. At the same BMI, Hispanic and Asian children are more susceptible to fatty liver disease than Black and white children. Weight reduction or reducing the consumption of fructose, a naturally occurring sugar and common food additive – even without significant weight loss – improves fatty liver.</p>
<p>Fatty liver is the most common chronic liver disease in children and adults. In Southern California, <a href="https://doi.org/10.1542%2Fpeds.2020-0771">pediatric fatty liver doubled</a> from 2009 to 2018. The disease can progress rapidly in children, and <a href="https://doi.org/10.1136/gut.2008.171280">some will have liver scarring</a> after only a few years. </p>
<p>Although few children currently require liver transplants for fatty liver, it is the most <a href="https://doi.org/10.1097/mcg.0000000000000925">rapidly increasing reason for transplantation in young adults</a>. Fatty liver is the second-most common reason for liver transplantation in the U.S., and it will be the <a href="https://liverfoundation.org/about-your-liver/facts-about-liver-disease/fatty-liver-disease/">leading cause in the future</a>.</p>
<figure class="align-center ">
<img alt="A light micrograph image of fatty liver, with large vacuoles of triglyceride fat accumulated inside liver cells." src="https://images.theconversation.com/files/524456/original/file-20230504-17-zbul98.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/524456/original/file-20230504-17-zbul98.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/524456/original/file-20230504-17-zbul98.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/524456/original/file-20230504-17-zbul98.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/524456/original/file-20230504-17-zbul98.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/524456/original/file-20230504-17-zbul98.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/524456/original/file-20230504-17-zbul98.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">A light micrograph image of fatty liver, with large vacuoles of triglyceride fat inside liver cells.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/light-micrograph-of-a-fatty-liver-royalty-free-image/851075118?phrase=fatty+liver&adppopup=true">Dr_Microbe/iStock via Getty Images Plus</a></span>
</figcaption>
</figure>
<h2>Links between obesity and diabetes</h2>
<p><a href="https://doi.org/10.1016/S2213-8587(14)70032-4">Fatty liver is implicated</a> in <a href="https://www.nhlbi.nih.gov/health/metabolic-syndrome">metabolic syndrome</a>, a group of conditions that cluster together and increase the risk of cardiovascular disease and diabetes.</p>
<p>In a telephone interview, Dr. Barry Reiner, a pediatric endocrinologist, voiced his concerns to me about obesity and diabetes.</p>
<p>“When I started my practice, I had never heard of type 2 diabetes in children,” says Reiner. “Now, depending on which part of the U.S., between a quarter and a third of new cases of diabetes are type 2.”</p>
<p><a href="https://www.mayoclinic.org/diseases-conditions/type-1-diabetes/symptoms-causes/syc-20353011">Type 1 diabetes</a> is an autoimmune disease previously called juvenile-onset diabetes. Conversely, <a href="https://www.mayoclinic.org/diseases-conditions/type-2-diabetes/symptoms-causes/syc-20351193">type 2 diabetes</a> was historically considered an adult disease. </p>
<p>However, type 2 diabetes is increasing in children, and obesity is the <a href="https://www.endocrine.org/news-and-advocacy/news-room/2017/childhood-obesity-quadruples-risk-of-developing-type-2-diabetes">major risk factor</a>. While both types of diabetes have genetic and lifestyle influences, type 2 is more modifiable through diet and exercise. </p>
<p>By 2060, the number of people under 20 with type 2 diabetes will <a href="https://doi.org/10.2337/dc22-0945">increase by 700%</a>. Black, Latino, Asian, Pacific Islander and Native American/Alaska Native children will have more type 2 diabetes diagnoses than white children. </p>
<p>“The seriousness of type 2 diabetes in children is underestimated,” says Reiner. He added that many people express a misconception that type 2 diabetes is a mild, slow-moving disease.</p>
<p>Reiner pointed to an important study showing that type 2 diabetes acquired in childhood <a href="https://www.adameetingnews.org/live-updates/session-coverage/today2-study-youth-onset-type-2-diabetes-more-severe-than-adult-onset-disease">can rapidly progress</a>. As early as 10 to 12 years after their childhood diagnosis, patients developed nerve damage, kidney problems and vision damage. By 15 years after diagnosis, at an average age of 27, almost <a href="https://doi.org/10.1056/NEJMoa2100165">70% of the patients had high blood pressure</a>.</p>
<p>Most patients had more than one complication. Although rare, a few patients experienced heart attacks and strokes. When people with childhood onset diabetes became pregnant, 24% delivered premature infants, over <a href="https://www.marchofdimes.org/peristats/reports/united-states/prematurity-profile#">double the rate in the general population</a>.</p>
<h2>Heart health</h2>
<p>Cardiovascular changes associated with obesity and severe obesity can also increase a child’s lifetime chance of heart attacks and strokes. Carrying extra weight at 6 to 7 years old can result in higher blood pressure, cholesterol and artery stiffness by <a href="https://doi.org/10.1542/peds.2019-3666">11 to 12 years of age</a>. Obesity <a href="https://doi.org/10.1093/eurheartj/ehv089">changes the structure of the heart</a>, making the muscle thicken and expand. </p>
<p>Although still uncommon, more people in their 20s, 30s and 40s <a href="https://doi.org/10.1161/STROKEAHA.119.024156">are having strokes</a> and <a href="https://www.acc.org/about-acc/press-releases/2019/03/07/08/45/heart-attacks-increasingly-common-in-young-adults">heart attacks</a> than a few decades ago. Although many factors may contribute to heart attack and stroke, obesity adds to that risk.</p>
<h2>Talk about being healthy, not focusing on weight</h2>
<p>Venus Kalami, a registered dietitian, spoke with me about the environmental and societal influences on childhood obesity.</p>
<p>“Food, diet, lifestyle and weight are often a proxy for something greater going on in someone’s life,” says Kalami.</p>
<p>Factors beyond a child’s control, including <a href="https://med.stanford.edu/news/all-news/2018/04/pediatric-obesity-depression-connected-in-the-brain.html">depression</a>, <a href="https://doi.org/10.1542/peds.2021-055571">access to healthy food</a> and <a href="https://doi.org/10.1210/endrev/bnac005">walkable neighborhoods</a>, contribute to obesity.</p>
<p>Parents may wonder how to help children without introducing shame or blame. First, conversations about weight and food should be age appropriate.</p>
<p>“A 6-year-old does not need to be thinking about their weight,” says Kalami. She adds that even preteens and teenagers should not be focusing on their weight, though they likely already are. </p>
<p>Even <a href="https://doi.org/10.1542/peds.2016-1649">“good-natured” teasing</a> is harmful. Avoid diet talk, and instead discuss health. Kalami recommends that adults explain how healthy habits can improve mood, focus or kids’ performance in a favorite activity.</p>
<p>“A 12-year-old isn’t always going to know what is healthy,” Kalami said. “Help them pick what’s available and make the best choice, which may not be the perfect choice.”</p>
<p>Any weight talk, either criticism or compliments for weight loss, may backfire, she adds. Praising a child for their weight loss can reinforce a negative cycle of disordered eating. Instead, cheer the child’s better health and good choices.</p>
<p>Dr. Muneeza Mirza, a pediatrician, recommends that parents model healthful behavior.</p>
<p>“Changes should be made for the whole family,” says Mirza. “It shouldn’t be considered a punishment for that kid.”</p><img src="https://counter.theconversation.com/content/202595/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Christine Nguyen does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>The American Academy of Pediatrics has recently released new obesity management guidelines in order to help address the growing obesity crisis in children.Christine Nguyen, 2023 California Health Equity Fellow, University of Southern CaliforniaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/2002282023-03-19T11:51:51Z2023-03-19T11:51:51Z3 ways to unlock the power of food to promote heart health<figure><img src="https://images.theconversation.com/files/515920/original/file-20230316-2393-gn90tf.jpg?ixlib=rb-1.1.0&rect=172%2C111%2C5146%2C3700&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Heart-healthy approaches to eating include the Mediterranean diet, the DASH diet and the Portfolio diet.</span> <span class="attribution"><span class="source">(Shutterstock)</span></span></figcaption></figure><p>Your diet — the foods and drinks you eat, not short-term restrictive programs — can impact your heart disease risk. Evidence-based approaches to eating are used by dietitians and physicians to prevent and treat cardiovascular (heart) disease. </p>
<p>National Nutrition Month, with its 2023 theme of <a href="https://www.dietitians.ca/Advocacy/Nutrition-Month/Nutrition-Month-2023?lang=en-CA">Unlock the Potential of Food</a>, is an ideal opportunity to learn more about these approaches and adopt more heart-friendly behaviours.</p>
<p>The <a href="https://doi.org/10.1016/j.cjca.2016.07.510">Canadian Cardiovascular Society (CCS) Clinical Practice Guidelines</a> recommend three main dietary patterns for lowering heart disease risk: the Mediterranean Diet, Dietary Approaches to Stop Hypertension (DASH) and the Portfolio Diet.</p>
<ol>
<li><p><strong>The Mediterranean Diet</strong> is rich in colourful vegetables and fruits, whole grains, legumes, nuts, olive oil and seafood. Research studies have shown that this diet <a href="https://doi.org/10.1056/nejmoa1800389">reduces risk of having a heart attack or stroke</a>, even <a href="https://doi.org/10.1016/s0140-6736(22)00122-2">if you already have heart disease</a>, and provides several other health benefits. <a href="https://www.dietitians.ca/DietitiansOfCanada/media/Documents/Mediterranean%20Diet%20Toolkit/Mediterranean-Diet-Toolkit-A-Guide-to-Healthy-Eating-(handout).pdf">Dietitians of Canada has created a resource</a> that summarizes the details of this approach to eating. </p></li>
<li><p><strong>The DASH Diet</strong> focuses on eating plenty of vegetables, fruit, low-fat dairy, whole grains and nuts, while limiting red and processed meats, foods with added sugar, and sodium. <a href="https://doi.org/10.3390/nu11020338">Originally developed to treat high blood pressure</a>, this diet can also lower low-density lipoprotein cholesterol (LDL-C — the unhealthy type of cholesterol) and provides several other health benefits. <a href="https://www.heartandstroke.ca/healthy-living/healthy-eating/dash-diet">Heart & Stroke has several resources</a> on this approach to eating. </p></li>
<li><p><strong>The Portfolio Diet</strong> was originally developed in Canada to treat high cholesterol. It emphasises plant proteins (for example, soy and other legumes); nuts; viscous (or “sticky”) fibre sources such as oats, barley and psyllium; plant sterols; and healthy oils like olive oil, canola oil and avocado. <a href="https://doi.org/10.1016/j.pcad.2018.05.004">Many research studies</a> have shown that this diet can lower LDL-C, and provides several other health benefits. Research shows that <a href="https://doi.org/10.1161/jaha.121.021515">even small additions of Portfolio Diet heart-healthy foods</a> can make a difference; the more you consume of these recommended foods, the greater your reductions in LDL-C and heart disease risk. The <a href="https://ccs.ca/app/uploads/2020/11/Portfolio_Diet_Scroll_editable_eng.pdf">Canadian Cardiovascular Society has an infographic</a> on how to follow the Portfolio Diet. </p></li>
</ol>
<p>A common theme among these three approaches to eating is that they are all considered plant-based, and small changes can make a difference in your overall heart disease risk. “Plant based” does not necessarily mean you have to be 100 per cent vegan or vegetarian to get their benefits. Plant-based diets can range from entirely vegan to diets that include small to moderate amounts of animal products.</p>
<p>Knowledge of healthy eating approaches is key, but behaviours unlock the power of food. Below are three strategies to use to apply the potential of food to promote heart health. They show that by combining the power of nutrition and psychology, you can <a href="https://www.newharbinger.com/9781684033331/healthy-habits-suck/">improve your chances of making long-term changes</a>.</p>
<p>You don’t need to do this alone. We recommend requesting a referral from your physician (this helps with getting the appointment covered by your insurance) to work with a registered dietitian and/or psychologist (behaviourist) to co-create your own ways to unlock the potential of food. </p>
<h2>3 ways to unlock the power of food</h2>
<figure class="align-center ">
<img alt="A woman in a white coat holding an apple, with a bowl of fresh produce on her desk, consulting with a woman who has her back to the camera" src="https://images.theconversation.com/files/516092/original/file-20230317-4846-oh3wlb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/516092/original/file-20230317-4846-oh3wlb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/516092/original/file-20230317-4846-oh3wlb.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/516092/original/file-20230317-4846-oh3wlb.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/516092/original/file-20230317-4846-oh3wlb.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/516092/original/file-20230317-4846-oh3wlb.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/516092/original/file-20230317-4846-oh3wlb.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Working with a registered dietitian or psychologist (behaviourist) can help you create a personalized plan to unlock the potential of food. A physician’s referral can help with getting the appointment covered by insurance.</span>
<span class="attribution"><span class="source">(Shutterstock)</span></span>
</figcaption>
</figure>
<h2>1. Master and conquer the 90 per cent goal</h2>
<p>Pick a goal you’re 90 per cent sure you can succeed at, while creating a plan to meet larger and harder goals in the future. This approach will help you build confidence in your skills and give you valuable information about what does and does not work for you.</p>
<p><a href="https://www.newharbinger.com/9781608824342/the-abcs-of-human-behavior/">Research shows</a> starting with 90 per cent goals makes it more likely we meet future goals. A 90 per cent goal could be swapping out animal protein for plant protein — such as tofu or beans — at lunch on Mondays (<a href="https://www.mondaycampaigns.org/meatless-monday">Meatless Mondays</a>). Another example: use a meal delivery service that provides measured ingredients with plant-based recipes on Monday, Wednesday and Friday, so you can get some new ideas about how to incorporate more plants into your meals.</p>
<h2>2. Why eliminate and restrict, when you can substitute?</h2>
<p>Pick a “do instead” goal or work with a registered dietitian to substitute healthier choices for your current foods and drinks. Avoid setting goals that may <a href="https://doi.org/10.1016/j.eatbeh.2010.03.001">make you focus MORE on the foods you’re trying to avoid</a> (for example, “stop eating sugar”).</p>
<p>Instead, the substitution approach can include things like choosing lower-sodium soup or purchasing pre-cut vegetables with the aim of reducing your starch portion at meals by half. <a href="https://food-guide.canada.ca/en/tips-for-healthy-eating/make-healthy-meals-with-the-eat-well-plate/">Canada’s Food Guide</a>, <a href="https://www.diabetes.ca/resources/tools---resources/basic-meal-planning">Diabetes Canada</a> and <a href="https://www.heartandstroke.ca/-/media/pdf-files/what-we-do/publications/living-well-with-heart-disease/chapter-3.ashx?rev=bae93023086643e8873730f4bd29b946">Heart & Stroke</a> recommend that half your plate be vegetables.</p>
<h2>3. Set value-based goals</h2>
<p>Connect your goal to something that deeply matters to you. While long-term outcomes (such as heart disease) may be the impetus for change, <a href="https://doi.org/10.1093/oxfordhb/9780197550076.013.18">research shows that things that matter to us right now motivate us most</a>. Picking personal and meaningful reasons for change will help with sustained change.</p>
<p>For example, choose to cook one meal that incorporates a vegetable with a close friend or family member, so you can share the experience and spend time together. This example may be rooted in the following values: kindness, relational values, cultural values, empathy, courage.</p>
<h2>Unlock the power of food</h2>
<p><a href="https://obesitycanada.ca/wp-content/uploads/2021/07/10-Psych-Interventions-2-v7-with-links-1.pdf">Research shows</a> a key to changing diet is focusing on changing eating habits and food behaviours, one at a time. The support of a nutrition professional, such as a registered dietitian and/or a psychologist, can help you make informed choices and plans, tailored to your unique needs, situation, preferences, traditions, abilities and capacity.</p><img src="https://counter.theconversation.com/content/200228/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Shannan M. Grant has received funding from Diabetes Canada, Dietitians of Canada and currently holds funding from Medavie, Tri-Council Funding Programs, Canadian Foundation for Dietetic Research, IWK Health, Mount Saint Vincent University. She is affiliated with Mount Saint Vincent University, IWK Health, Dalhousie University, Dietitians of Canada, Diabetes Canada, People in Pain (PIPN), and Dr. Dayna Lee-Baggley and Associates.</span></em></p><p class="fine-print"><em><span>Andrea J. Glenn receives postdoctoral research funding from the Canadian Institutes of Health Research (CIHR). She has received honoraria from the Soy Nutrition Institute (2020) and the Academy of Nutrition and Dietetics (2022). </span></em></p><p class="fine-print"><em><span>Dayna Lee-Baggley, Ph.D, Registered Psychologist owns shares in Dr. Lee-Baggley and Associates. She has received funding in the past from the Kidney Foundation of Canada (research grant), QEII Foundation (research grant), CIHR (research grant), SSHRC (research grant) and honoraria/speaking fees from Tobacco Free Nova Scotia, Bausch Health, and Novo Nordisk. She receives royalties from New Harbinger. </span></em></p>Research shows the key to changing your diet is focusing on changing eating habits and food behaviours, one at a time.Shannan M. Grant, Associate Professor, Registered Dietitian, Department of Applied Human Nutrition, Mount Saint Vincent UniversityAndrea J. Glenn, Postdoctoral research fellow, Department of Nutrition, Harvard T.H. Chan School of Public Health, Harvard UniversityDayna Lee-Baggley, Adjunct professor, Department of Family Medicine & Department of Psychology and Neuroscience, Dalhousie UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1948982022-12-26T20:52:15Z2022-12-26T20:52:15ZHeart rate variability – what to know about this biometric most fitness trackers measure<figure><img src="https://images.theconversation.com/files/500755/original/file-20221213-14408-pvtw3d.jpg?ixlib=rb-1.1.0&rect=1047%2C901%2C6039%2C3884&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">An increase in this particular biometric is a good thing.</span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/senior-man-using-smartwatch-in-bed-royalty-free-image/1371086366">visualspace/E+ via Getty Images</a></span></figcaption></figure><p>Your heart beats <a href="https://www.pbs.org/wgbh/nova/heart/heartfacts.html">around 100,000 times every day</a>. <a href="https://theconversation.com/tracking-your-heart-rate-5-questions-answered-about-what-that-number-really-means-124066">Heart rate</a> is a key marker of cardiovascular activity and an important vital sign. But your pulse is not as steady as a precision clock – nor would you want it to be.</p>
<p><a href="https://scholar.google.com/citations?hl=en&user=uXcM0scAAAAJ">As a cardiovascular physiologist</a>, I measure heart rate in nearly every experiment my students and I perform. Sometimes we use an <a href="https://medlineplus.gov/lab-tests/electrocardiogram/">electrocardiogram</a>, such as you’d see in a medical clinic, which uses sticky electrodes to measure electrical signals between two points of your body. Other times we use a chest strap monitor, like ones you might see on someone at the gym, which also detects heartbeats based on electrical activity.</p>
<p>As wearable technology has grown more popular, it’s not just researchers and cardiologists who are paying attention to heart rate. You might be monitoring your own all day long via a fitness tracker you wear on your wrist. This kind of wearable device <a href="https://help.fitbit.com/articles/en_US/Help_article/1565.htm">uses green light to detect blood flow</a> beneath your skin and deduces your heart rate.</p>
<p>Here are what heart rate and other measurements derived from this biometric can tell you about your body’s health.</p>
<h2>Pumping blood where it needs to go</h2>
<p>The heart’s primary job is to contract and generate pressure that helps pump blood to the lungs to be oxygenated and then on to the rest of the body to deliver oxygen and other nutrients. Heart rate is simply how fast your heart is beating. Sometimes called a pulse rate, it’s normally presented in beats per minute. You can <a href="https://www.health.harvard.edu/heart-health/want-to-check-your-heart-rate-heres-how">count your own heart rate</a> by feeling for your pulse inside your wrist or behind your jaw. </p>
<p>When your body demands more oxygen, such as during exercise, heart rate will increase along with the increasing workloads.</p>
<p>While many people are familiar with tracking their heart rate during exertion, the heart rate at rest can also provide valuable information. The two parts of the <a href="https://www.webmd.com/heart/what-is-heart-rate-variability">autonomic nervous system</a>, the sympathetic and parasympathetic, influence resting heart rate. The sympathetic branch helps coordinate your body’s stress response. The more active it is, the higher it dials up your heart rate, preparing you for fight or flight. </p>
<p>The parasympathetic branch of your nervous system is responsible for keeping lots of your body’s functions running smoothly while you’re at ease. Via the vagus nerve that runs from the brain all the way to the abdomen, the parasympathetic nervous system actively slows the heart down to resting values between <a href="https://www.heart.org/en/health-topics/high-blood-pressure/the-facts-about-high-blood-pressure/all-about-heart-rate-pulse">60 and 100 beats</a> per minute for the average healthy adult. Without any parasympathetic activity putting the brakes on the sympathetic nervous system’s signals, your heart would beat at approximately 100 beats per minute. </p>
<p>A lower resting heart rate indicates an efficient heart and a higher level of parasympathetic activity. When you’re at rest your nervous system is ideally minimizing sympathetic activity, so you’re conserving energy and avoiding unnecessary stress to the body.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/500523/original/file-20221212-119183-4pofku.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="chart of red peaks of a heartbeat at slightly different intervals" src="https://images.theconversation.com/files/500523/original/file-20221212-119183-4pofku.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/500523/original/file-20221212-119183-4pofku.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=274&fit=crop&dpr=1 600w, https://images.theconversation.com/files/500523/original/file-20221212-119183-4pofku.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=274&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/500523/original/file-20221212-119183-4pofku.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=274&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/500523/original/file-20221212-119183-4pofku.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=344&fit=crop&dpr=1 754w, https://images.theconversation.com/files/500523/original/file-20221212-119183-4pofku.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=344&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/500523/original/file-20221212-119183-4pofku.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=344&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The chart of a heart rate reveals tiny differences in spacing between the peaks representing heartbeats.</span>
<span class="attribution"><span class="source">YitzhakNat via Wikimedia Commons</span>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<h2>Time between each heartbeat</h2>
<p>One specific way to understand the balance of the nervous system’s influence on heart rate is to look at <a href="https://my.clevelandclinic.org/health/symptoms/21773-heart-rate-variability-hrv#:%7E:text=Heart%20rate%20variability%20is%20where,issues%20like%20anxiety%20and%20depression.">heart rate variability</a>, or HRV – the slight fluctuation in the time between each heartbeat. Even if your heart rate is 60 beats a minute, that doesn’t mean your heart is pumping exactly once every second.</p>
<p>Less variability is a sign that your body is under greater stress and that the balance in your autonomic nervous system is tipping toward the sympathetic branch being in charge. Greater variability suggests you’re more relaxed and your parasympathetic nervous system is in control. </p>
<p>For nearly 30 years, scientists have been interested in <a href="https://doi.org/10.1161/01.CIR.93.5.1043">how to measure and interpret HRV</a>, specifically as it relates to this balance of autonomic control.</p>
<p>The clinical utility of HRV emerged in patients following cardiac events, but researchers are now considering how this measure can help explain patient outcomes in a range of <a href="https://doi.org/10.2147/VHRM.S279322">cardiac</a>, <a href="https://doi.org/10.1371/journal.pone.0195166">endocrine</a> and <a href="https://doi.org/10.1016/j.jad.2018.04.071">psychiatric</a> disorders.</p>
<p>More recently, researchers have investigated <a href="https://doi.org/10.15420/aer.2018.27.2">how to use HRV</a> in <a href="https://doi.org/10.15420/aer.2018.30.2">athletic training and prognosis of medical conditions</a>.</p>
<p>Several fitness wearables also report <a href="https://support.whoop.com/WHOOP_Data/Recovery__HRV/What_is_Heart_Rate_Variability_(HRV)%3F">heart rate variability</a>, either as a <a href="https://support.ouraring.com/hc/en-us/articles/360025441974-An-Introduction-to-Heart-Rate-Variability#:%7E:text=How%20Oura%20Measures%20HRV,samples%20measured%20while%20you%20sleep.">stand-alone metric</a> or used in the calculation of “readiness” or “recovery” scores. <a href="https://doi.org/10.1055/a-1864-9726">Endurance athletes now commonly track HRV</a> as one way to monitor their overall physiological state.</p>
<p>Researchers have started checking which <a href="https://doi.org/10.3390/s22166317">commercially available wearable devices are most reliable and accurate</a> at measuring HRV, which can vary from tracker to tracker. Many of these devices use colored lights, or optical sensors, to measure pulse rate and other variables at the wrist or finger. Unfortunately, the <a href="https://www.statnews.com/2019/07/24/fitbit-accuracy-dark-skin/">accuracy of this method can vary based on skin type and skin color</a>. It is important that companies include diverse populations in the design, testing and validation of these products to help address potential racial health disparities.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/500758/original/file-20221213-19390-g5huck.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="woman doing standing pose on yoga mat" src="https://images.theconversation.com/files/500758/original/file-20221213-19390-g5huck.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/500758/original/file-20221213-19390-g5huck.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/500758/original/file-20221213-19390-g5huck.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/500758/original/file-20221213-19390-g5huck.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/500758/original/file-20221213-19390-g5huck.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/500758/original/file-20221213-19390-g5huck.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/500758/original/file-20221213-19390-g5huck.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Another health benefit of stress-busting activities can be an increase in heart rate variability.</span>
<span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/woman-standing-on-yoga-mat-in-warrior-pose-while-royalty-free-image/1397801043">David Espejo/Moment via Getty Images</a></span>
</figcaption>
</figure>
<h2>Nudging HRV in a good direction</h2>
<p>One of the biggest influences on heart rate variability is stress; along with increased sympathetic nervous system activity, stress is associated with lower HRV. Stress-reducing interventions, <a href="https://my.clevelandclinic.org/health/treatments/13354-biofeedback">biofeedback</a> and <a href="https://doi.org/10.1016/s0828-282x(10)70395-0">increased fitness</a> can increase heart rate variability. Remember, an increase is good for this metric. Overall, <a href="https://www.webmd.com/heart/what-is-heart-rate-variability#091e9c5e82171840-2-4">heart rate variability depends on</a> a range of physiological, psychological, environmental, lifestyle and nonmodifiable genetic <a href="https://doi.org/10.3389/fpubh.2017.00258">factors</a>.</p>
<p>The most useful way to consider heart rate variability as a metric is to look at data trends. Are there consistent changes in HRV in either direction? Examine these changes alongside other health factors such as fitness, mood, illness, sleep and dietary intake to see if you can draw any conclusions about lifestyle modifications you may want to make.</p>
<p>In general, the <a href="https://www.va.gov/WHOLEHEALTHLIBRARY/tools/heart-rate-variability-and-arrhythmias.asp">same approaches</a> you would take to lowering resting heart rate can also improve heart rate variability, such as increasing cardiovascular fitness, maintaining a healthy weight, reducing stress and getting sufficient sleep.</p>
<p>It’s important to remember that heart rate variability is the normal, healthy, very slight fluctuation of timing of heartbeats – just milliseconds of difference from beat to beat. More dramatic changes in heart rhythms or the way in which the heart contracts, known as <a href="https://www.mayoclinic.org/diseases-conditions/heart-arrhythmia/symptoms-causes/syc-20350668">arrhythmias</a>, may signal a more serious condition that requires medical attention.</p><img src="https://counter.theconversation.com/content/194898/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Anne R. Crecelius does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Tiny fluctuations in the time between each beat of your heart can provide clues about how much stress your body is experiencing.Anne R. Crecelius, Associate Professor of Health and Sport Science, University of DaytonLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1871052022-07-21T10:19:10Z2022-07-21T10:19:10Z‘Weekend warrior’ exercise still lowers risk of premature death – new research<figure><img src="https://images.theconversation.com/files/474820/original/file-20220719-12-v65214.jpg?ixlib=rb-1.1.0&rect=14%2C14%2C4760%2C3168&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Only exercising on weekends can still be good for your health.</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/elevated-view-busy-gym-people-exercising-289557899">Monkey Business Images/ Shutterstock</a></span></figcaption></figure><p>We’re all told time and again just how important it is to exercise for good health. But with our busy schedules, <a href="https://www.researchgate.net/profile/Stewart-Trost/publication/11001088_Correlates_of_adults'_participation_in_physical_activity_Review_and_update/links/57031b3808aea09bb1a3089f/Correlates-of-adults-participation-in-physical-activity-Review-and-update.pdf">finding the time to work out</a> is often easier said than done. For many of us, the weekend is the only time we can get to the gym or go for a run.</p>
<p>UK exercise guidelines suggest that adults should do at least 150 minutes of moderate exercise (or 75 minutes of vigorous exercise) a week for good health. But debate is growing around the issue of whether or not you can still get the <a href="https://academic.oup.com/eurjpc/article/15/3/239/5933086">benefits of exercise</a> if you squeeze it all in on a weekend (sometimes called “weekend warrior” exercise) instead of spreading it throughout the week. This is what a recent study sought to find out.</p>
<p>They found that weekend warrior exercise still has <a href="https://jamanetwork.com/journals/jamainternalmedicine/article-abstract/2596007">many benefits to health</a> – with the study showing people who only exercise two days a week had lower risk of premature death from any cause, compared to people who do not exercise. But, they also found that spreading your workouts throughout the week was associated with the greatest benefits for your health.</p>
<p>To conduct their study, the researchers looked at more than 60,000 adults aged 40 and over. Data on the participants was collected by the <a href="https://digital.nhs.uk/data-and-information/publications/statistical/health-survey-for-england">Health Survey for England</a> and the <a href="https://www.gov.scot/collections/scottish-health-survey/">Scottish Health Survey</a> between 1994 and 2012. Participants were also asked about their exercise habits.</p>
<p>Participants were then categorised as being a “weekend warrior” (meeting recommended activity guidelines over a minimum one to two days per week), “regularly active” (meeting recommended activity guidelines over a minimum of three days per week), “insufficiently active” (exercising less than recommended) or “inactive”. Using data from the surveys and The British National Health Service Central Registry for Deaths, the authors then compared how many from each category had died during the study. </p>
<p>Weekend warrior exercisers had a 30% lower risk of premature death from all causes compared to inactive people. Risk of death from cardiovascular disease was also around 40% lower, while risk of death from all types of cancer was around 18% lower compared to those who were inactive.</p>
<p>Of course, regularly active people had the best health overall – and had a 5% lower risk of premature death from any cause compared to weekend warriors. This finding is consistent with <a href="https://www.sciencedirect.com/science/article/pii/S0091743515002662?casa_token=s3fn0BZS_dEAAAAA:f7YjhB13G92AieKCD15IkI36VHuOgxHo7R9AXF9iEZ8G1I16xpga--fKbG6G5nM0zVt_h2624b0">previous research</a>, which suggests the more exercise you do, the more beneficial it is to your health. But this is only true up to a certain point – with research showing that doing more than five times the minimum recommended weekly activity (the equivalent of around 12.5 hours of moderately exercise, or just over six hours of vigorous activity) has no added benefits. </p>
<h2>Weekend warriors</h2>
<p>It’s well-known that exercise improves our <a href="https://bmcpublichealth.biomedcentral.com/articles/10.1186/s12889-020-09801-3">cardiorespiratory fitness</a>, which is important for making sure our heart and lungs function effectively. Not only does this allow us to exercise longer and more intensely, it also improves other aspects of our health – such as lowering blood pressure. This is also likely the reason research shows people who exercise regularly have lower risk of premature death from any cause.</p>
<figure class="align-center ">
<img alt="An adult couple go for a run in the city." src="https://images.theconversation.com/files/474824/original/file-20220719-24-oldnle.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/474824/original/file-20220719-24-oldnle.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/474824/original/file-20220719-24-oldnle.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/474824/original/file-20220719-24-oldnle.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/474824/original/file-20220719-24-oldnle.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/474824/original/file-20220719-24-oldnle.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/474824/original/file-20220719-24-oldnle.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Exercise leads to a number of beneficial changes in our body.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/out-run-full-length-young-couple-738806251">G-Stock Studio/ Shutterstock</a></span>
</figcaption>
</figure>
<p>Exercise also lowers body fat and reduces inflammation, which may all explain why physical activity reduces <a href="https://bjsm.bmj.com/content/bjsports/50/6/339.full.pdf">risk of death from cancer</a>. </p>
<p>But research shows that <a href="https://web.archive.org/web/20040928012207id_/http:/www.unm.edu:80/%7Errobergs/MetabolismDetraining.pdf">how often you exercise</a> is also important for <a href="https://journals.lww.com/nsca-jscr/Fulltext/2021/05000/Maintaining_Physical_Performance__The_Minimal_Dose.35.aspx?context=FeaturedArticles&collectionId=1&casa_token=R69HMZQjiJEAAAAA:VBigmQ5iavbKUIVBBopFpL0jd2pxqKh2mwkl_F-xt64e16p-LOJUBq52Smj7oGmISzUpA2wUEFLbjpWonfEfVeIwvOohql4">improving and maintaining fitness</a>. In fact, as little as <a href="https://web.archive.org/web/20040928012207id_/http:/www.unm.edu:80/%7Errobergs/MetabolismDetraining.pdf">72 hours</a> between workouts is enough for “detraining” to happen. This refers to the partial or complete loss of training adaptations (such as better cardiovascular function) that happens when we stop exercising. While some detraining is likely to happen in people who only exercise on weekends, consistently training – even if it’s only on weekends – will still lead to adaptations that are good for health.</p>
<p>While this research gives hope to those who can’t exercise regularly, it must be interpreted with caution. The study has limitations, as acknowledged by the authors. The data was self-reported by participants, some of whom may have embellished the <a href="https://bjsm.bmj.com/content/37/3/197">amount of exercise</a> they really did. Also, the amount of exercise participants reported on only referred to the amount they did in the four weeks prior to the interview, which might not actually represent how much they did for the duration of the 20-year study. The researchers also excluded the physical activity a person did as part of their job. This is relevant as it can also contribute to <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2027542/pdf/brmedj03082-0009.pdf">lower risk of death</a> from disease.</p>
<p>The key message from this study is that doing some physical activity is better than doing nothing. So if you can only get your workouts in on weekends, you’re still likely to have better health compared to someone who does not exercise regularly. But the more regular physical activity you can do, the better.</p>
<p>Exercise, combined with a <a href="https://www.nejm.org/doi/full/10.1056/nejmra1203528">proper diet</a>, is essential for good health. Adding in <a href="https://journals.sagepub.com/doi/pdf/10.1177/2047487319850718?casa_token=bNUtL0_-nhgAAAAA:1CB1H_asBrO2k6Y1lAmKCYtV95AQ0DQloJ7E4WXWeP-bIcRrUDEMgvR-4tg6WKkQ9nBObTPGHBqTbw">resistance training</a> (such as weight lifting) alongside cardio may help further boost the benefits of exercise on your health.</p><img src="https://counter.theconversation.com/content/187105/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>The authors do not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.</span></em></p>So-called ‘weekend warriors’ had a 30% lower risk of death from any cause compared to those who never exercised.Jonathan Taylor, Lecturer in Sport and Exercise, Teesside UniversityMichael Graham, Senior Lecturer in Sport and Exercise Science, Teesside UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1835912022-06-08T12:33:31Z2022-06-08T12:33:31ZNo, Latinos don’t actually have less heart disease – a new large study refutes the longstanding ‘Latino paradox’<figure><img src="https://images.theconversation.com/files/467233/original/file-20220606-20-3pn9ey.jpg?ixlib=rb-1.1.0&rect=233%2C0%2C4958%2C3362&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">For at least three decades, studies have shown that Latinos have better heart health than other people, but new research calls that into question. </span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/grandmother-teaching-granddaughter-to-cook-in-royalty-free-image/1312462880?adppopup=true">The Good Brigade/DigitalVision via Getty Images</a></span></figcaption></figure><p><em>The <a href="https://theconversation.com/us/topics/research-brief-83231">Research Brief</a> is a short take about interesting academic work.</em> </p>
<h2>The big idea</h2>
<p>Latinos may have higher rates of heart disease than previously thought, refuting a well-accepted idea known as the “Latino paradox,” according to a <a href="https://doi.org/10.1007/s11606-022-07625-y">new study that I was involved in</a>.</p>
<p>The crux of the Latino paradox is as follows: A broad body of research shows that Latinos have <a href="https://www.diabetesresearch.org/file/national-diabetes-statistics-report-2020.pdf">higher rates of diabetes</a>, <a href="https://doi.org/10.1001/jama.2020.14590">obesity</a> and <a href="https://doi.org/10.1097/HCO.0000000000000636">uncontrolled blood pressure</a> and <a href="https://doi.org/10.1161/JAHA.115.001867">cholesterol levels</a> than non-Hispanic white people. So naturally, it would follow that Latino people should also have higher levels of cardiovascular disease. </p>
<p>But for the past 30 years, <a href="https://doi.org/10.2105/AJPH.2012.301103">a wide body of studies</a> has found the opposite: Despite greater risk factors for heart disease, Latinos have lower mortality from rates of heart disease than non-Latino people. </p>
<p>We found, however, that both Latino men and women have significantly higher rates of heart disease than non-Hispanic whites. In fact, for men we found rates of heart disease that were even slightly higher than among Black people, a group with <a href="https://doi.org/10.1161/cir.0000000000000534">the highest rates of heart disease</a>. We found that 9.2% of Latinos had a diagnosis of heart disease, compared with 8.1% among Black people and 7.6% among non-Hispanic white men. </p>
<p>To do the analysis, we used data from <a href="https://doi.org/10.1056/NEJMsr1809937">the All of Us research program</a>, which seeks to enroll at least 1 million people from diverse backgrounds over the next few years. We examined medical record data from the more than 200,000 people who have already signed up for the program, <a href="https://doi.org/10.1371/journal.pone.0234962">including over 40,000 Latinos</a>. </p>
<p>Going into the study, we assumed that we would find evidence in support of the Latino paradox. Prior data on the paradox was based mostly on mortality records or self-reporting, both of which have inherent limitations. For example, without an autopsy, it is often hard to know for certain what led to a person’s death. People also may not be aware that they had heart disease, especially if they have not seen a doctor in a long time.</p>
<p>Instead, our work looked at medical records and examined diagnoses of heart disease as determined by a physician during health care visits. We think this is a novel approach, as it uses more robust data to examine this issue. </p>
<h2>Why it matters</h2>
<p>The widely accepted <a href="https://doi.org/10.1016/j.ejim.2013.09.003">“Latino paradox</a>” has been studied extensively. And until now, most <a href="https://doi.org/10.1016/j.pcad.2014.09.001">studies have supported it</a>, though none have found a <a href="https://theconversation.com/the-cheerful-lexicon-of-the-spanish-language-may-help-solve-a-health-mystery-called-the-hispanic-paradox-173598">concrete explanation for it</a>. Medical and public health students are often taught about it as an unexplained phenomenon. But our study, using the largest research cohort of Latinos in the United States, seems to refute the paradox.</p>
<p>The implications are critical because they suggest that like all groups, Latinos still need to take care of themselves by eating healthily, exercising regularly, watching their weight, avoiding smoking and getting regular check-ups. Those with diabetes, hypertension or cholesterol, need to make sure those conditions are well-controlled. </p>
<p>These seemingly straightforward messages are the ones that doctors have been telling all of their patients for decades. Yet this study makes it clear that Latinos don’t get a free pass when it comes to heart disease and that they also need to follow health guidelines. And our study highlights the ongoing need for culturally tailored cardiovascular health programs for the Latino community. </p>
<h2>What is still unknown</h2>
<p>Although our study analyzed data from the largest existing cohort of Latinos, we do not think ours is the definitive word on the topic. More research is needed, and we need to continue to think creatively about how to get at these questions. It is also important to keep in mind that Latino populations are not homogeneous. Latinos come from many different parts of Latin America, where diets, customs and lifestyles are all unique.</p>
<p>For that reason, our team is interested in looking at health data focused on Latino subgroups, as well as comparing U.S.-born Latinos with immigrants. We also hope to examine the Latino paradox when it comes to other conditions such as cancer, which research has also shown occurs <a href="https://doi.org/10.3322/caac.21695">less frequently among Latinos than other groups</a>. That is another paradox that we need to reexamine.</p><img src="https://counter.theconversation.com/content/183591/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Olveen Carrasquillo receives funding from National Institutes of Health (NIH) and Patient Centered Outcomes Research Institute (PCORI).</span></em></p>It has long puzzled researchers why Latinos seem to have lower rates of heart disease than their non-Latino counterparts, even though they have higher risk factors for heart disease.Olveen Carrasquillo, Professor of Medicine and Public Health Sciences, University of MiamiLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1812342022-04-18T11:52:27Z2022-04-18T11:52:27ZCardiac rehab for heart patients saves lives and money, so why isn’t it used more?<figure><img src="https://images.theconversation.com/files/458242/original/file-20220414-18-37ha6h.jpg?ixlib=rb-1.1.0&rect=0%2C120%2C2232%2C1473&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Cardiac rehab is an outpatient chronic disease management program covering exercise, diet, lifestyle and psychosocial elements in hour-long sessions about twice per week over several months.</span> <span class="attribution"><span class="source">THE CANADIAN PRESS/Aaron Vincent Elkaim</span></span></figcaption></figure><p>Despite all the attention on COVID-19, <a href="https://www150.statcan.gc.ca/n1/daily-quotidien/220124/dq220124a-eng.htm">heart disease remains one of the biggest health threats</a>. Indeed, many people have <a href="https://doi.org/10.3390/ijerph19031108">not taken care of their heart health during the pandemic</a>, and are experiencing reduced quality of life because of it. If you’re reading this from the sofa with a bag of potato chips, this may include you.</p>
<p>Cardiac rehabilitation mitigates this, yet only <a href="http://dx.doi.org/10.1007/s11886-021-01543-x">10 to 25 per cent of heart patients</a> access it. It helps if patients and their loved ones are aware of cardiac rehab <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3176827/">and ask their doctor for a referral</a>, but there are <a href="https://doi.org/10.3390/jcm8020189">established strategies</a> to ensure patients access these programs that we desperately need to implement. </p>
<p>As a cardiac rehabilitation researcher for the past 20 years, I work with the preventive cardiology community to ensure more patients access these lifesaving programs.</p>
<h2>What cardiac rehab is all about</h2>
<p>Heart diseases are chronic and without cure, so they <a href="https://doi.org/10.1093/eurheartj/ehu505">often result in further cardiac events</a> such as readmission to the hospital or needing a stent — a tiny tube put in a vessel in your heart muscle to keep it open so oxygen and nutrient-rich blood can flow to it. But the chances of this can be drastically lowered with the <a href="https://doi.org/10.1016/j.mayocp.2016.12.024">low-cost, comprehensive cardiac rehab approach</a>.</p>
<figure class="align-right ">
<img alt="A stethoscope wrapped around an apple." src="https://images.theconversation.com/files/458223/original/file-20220414-18-xnpkkt.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/458223/original/file-20220414-18-xnpkkt.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=900&fit=crop&dpr=1 600w, https://images.theconversation.com/files/458223/original/file-20220414-18-xnpkkt.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=900&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/458223/original/file-20220414-18-xnpkkt.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=900&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/458223/original/file-20220414-18-xnpkkt.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1131&fit=crop&dpr=1 754w, https://images.theconversation.com/files/458223/original/file-20220414-18-xnpkkt.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1131&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/458223/original/file-20220414-18-xnpkkt.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1131&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Cardiac rehab includes exercise, diet, lifestyle and psychosocial counselling.</span>
<span class="attribution"><span class="source">(Piqsels)</span></span>
</figcaption>
</figure>
<p>Cardiac rehab is an outpatient chronic disease management program, offering patients hour-long sessions about twice per week over several months. <a href="http://dx.doi.org/10.1136/heartjnl-2015-309209">Programs offer</a> structured exercise, patient education, as well as lifestyle (such as diet, tobacco use, medication adherence) and psychosocial (things like depression, anxiety, sleep, stress, sex, as applicable) counselling. Think of it as one-stop shopping for <a href="https://doi.org/10.1093/eurheartj/ehab484">all the proven recommendations to lower your heart disease risk</a>, delivered in a co-ordinated way with your acute care physicians and primary care provider over time. We are the middle link in a chain that supports patients to thrive.</p>
<p>Cardiac rehabilitation is “not just broccoli and running shoes” as our medical director likes to say; participation <a href="https://doi.org/10.1002/14651858.CD001800.pub4">reduces death and hospitalization by more than 20 per cent</a>, and also <a href="https://doi.org/10.1016/j.cjca.2018.11.013">improves well-being</a> and supports return to desired life roles. Yet few heart patients receive it, while other heart care recommendations like medication are <a href="https://doi.org/10.1016/j.ahj.2016.04.002">implemented over 80 per cent</a> of the time.</p>
<p>As a cardiac rehabilitation community, we have done the research to establish what can rectify this. This includes innovative health system payment models, <a href="https://doi.org/10.1038/nrcardio.2009.223">automatic electronic referral</a>, clinician training courses, and tech-based cardiac rehabilitation. <a href="https://doi.org/10.3399/bjgp08X342219">Unfortunately things have not changed</a> and patients are not getting the support they need. </p>
<h2>Paying for cardiac rehab</h2>
<p>In Canada and other countries, health-care providers cannot directly bill government health-care systems for cardiac rehabilitation like they can for a stent or a cardiologist visit, despite all the <a href="https://doi.org/10.1161/CIR.0b013e318235eb4d">clinical recommendations</a> for patients to get rehab. We <a href="https://doi.org/10.1186/s12913-016-1658-1">advocate for this reimbursement</a>, or other innovative payment models, to make it more financially viable to offer cardiac rehab and ensure enough cardiac rehab spots for all the patients who need it.</p>
<figure class="align-center ">
<img alt="A man on a treadmill with a trainer beside him" src="https://images.theconversation.com/files/458225/original/file-20220414-24-8vrlvr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/458225/original/file-20220414-24-8vrlvr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/458225/original/file-20220414-24-8vrlvr.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/458225/original/file-20220414-24-8vrlvr.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/458225/original/file-20220414-24-8vrlvr.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/458225/original/file-20220414-24-8vrlvr.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/458225/original/file-20220414-24-8vrlvr.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Automatically flagging stent patients for referral to cardiac rehab may help improve access rates.</span>
<span class="attribution"><span class="source">(Shutterstock)</span></span>
</figcaption>
</figure>
<p>For example, if a patient gets a stent or heart bypass surgery, the hospital could be paid one <a href="https://www.commonwealthfund.org/publications/2020/apr/bundled-payment-models-around-world-how-they-work-their-impact">“bundled” fee</a> that includes money not only for the procedure, but also the rehabilitation that follows. <a href="https://www.health.gov.on.ca/en/pro/programs/ecfa/funding/ifm/">Bundled payments that include rehab have been rolled out now for hip and knee replacements in Ontario</a> for example, but we are still waiting for <a href="http://www.hqontario.ca/Portals/0/Documents/evidence/clinical-handbooks/heart-failure-02042015-en.pdf">heart procedures as promised</a>.</p>
<p>As a cardiac rehab advocate, I’ve heard the argument that heart risks are lifestyle-related, and government-funded health systems should not be in the business of individual health behaviour change. This is despite evidence that cardiac rehabilitation is cost-effective, results in <a href="https://doi.org/10.1002/14651858.CD010748.pub2">earlier return to work</a>, as well as <a href="https://doi.org/10.3390/jcm7120514">reductions in deaths and repeat visits to the hospital</a> (which are <a href="https://doi.org/10.1016/S0828-282X(09)70098-4">very expensive for the health system</a>).</p>
<p>Moreover, the same unhealthy lifestyle behaviours that underlie heart disease <a href="https://doi.org/10.1161/CIRCULATIONAHA.112.001183">are also associated with cancer</a>, but we don’t blame cancer patients for their condition. </p>
<p>Arguably, it is lack of public policy — to ensure citizens have access to safe <a href="https://doi.org/10.1371/journal.pone.0226524">green spaces</a> to exercise, <a href="https://doi.org/10.1161/JAHA.118.010694">sources of healthy food</a> and <a href="https://doi.org/10.1038/s41569-020-0371-2">clean air</a> in all neighbourhoods regardless of socio-economic status, as well as <a href="http://doi.org/10.1016/j.gheart.2015.04.007">better tobacco control</a> — that leads to heart disease; so governments clearly have an important role in lifestyle change. </p>
<figure class="align-center ">
<img alt="Illustration of an EKG heartbeat readout incorporating a figure running and a heart" src="https://images.theconversation.com/files/458224/original/file-20220414-18-ejdmfe.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/458224/original/file-20220414-18-ejdmfe.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=258&fit=crop&dpr=1 600w, https://images.theconversation.com/files/458224/original/file-20220414-18-ejdmfe.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=258&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/458224/original/file-20220414-18-ejdmfe.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=258&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/458224/original/file-20220414-18-ejdmfe.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=324&fit=crop&dpr=1 754w, https://images.theconversation.com/files/458224/original/file-20220414-18-ejdmfe.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=324&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/458224/original/file-20220414-18-ejdmfe.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=324&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Participation in cardiac rehab reduces death and hospitalization by more than 20 per cent improves well-being and supports return to desired life roles.</span>
<span class="attribution"><span class="source">(Pixabay)</span></span>
</figcaption>
</figure>
<p>People need support to learn how to manage their condition and change multiple health behaviours, as well as to address their <a href="https://doi.org/10.1016/j.rehab.2016.09.002">high rate of psychosocial issues</a> that not only hinder their ability to manage their condition but also result in <a href="https://doi.org/10.1038/nrcardio.2016.181">poorer health outcomes</a>.</p>
<p>Other solutions include leveraging electronic health records so that, for example, when a heart patient gets a stent or bypass surgery, their file is flagged automatically for cardiac rehab because of its <a href="https://doi.org/10.1038/s41569-021-00611-7">clear benefits</a> in these patients. Systematic referrals such as these <a href="https://doi.org/10.1001/archinternmed.2010.501">increase rehab use eight times</a>, and this is augmented even further by <a href="https://globalcardiacrehab.com/CR-Utilization">training inpatient clinicians</a> to inform and encourage patients to enrol in cardiac rehabilitation at the bedside.</p>
<h2>Reaching the patients most in need</h2>
<p>Finally, we can also deliver cardiac rehab broadly <a href="https://doi.org/10.2196/18773">using technology</a> to reach all patients in need. The 10-to-25-per-cent rates of rehabilitation use are an average. Use is even lower in certain populations such as <a href="https://doi.org/10.1016/j.cjca.2013.11.007">women</a>, <a href="https://doi.org/10.1007/s40615-018-0478-x">rural and racialized people</a> as well as <a href="https://doi.org/10.1097/HCR.0000000000000646">people of low-income in Canada</a> and <a href="http://dx.doi.org/10.1136/heartjnl-2018-314486">around the world</a>. And this is particularly disconcerting because <a href="https://doi.org/10.1016/j.jacc.2020.11.010">in lower-income countries, heart disease rates are epidemic</a>.</p>
<p>Many middle-income countries are now developing cardiology programs as the burden of disease shifts from communicable to non-communicable. Disconcertingly, these advanced centres are <a href="http://usa.chinadaily.com.cn/china/2012-10/15/content_15816265.htm">placing stents at high rates</a>, but often <a href="https://doi.org/10.1016/j.ahj.2009.06.020">neglect cardiac rehabilitation</a>, <a href="http://dx.doi.org/10.1136/heartjnl-2017-312809">which is lower cost</a> and in many cases of <a href="https://doi.org/10.1093/eurjpc/zwab191">similar</a> or <a href="https://doi.org/10.1161/01.CIR.0000121360.31954.1F">better</a> benefit. Moreover, doctors prefer to specialize in interventional rather than preventive cardiology as it is <a href="https://doi.org/10.1001/jamainternmed.2018.8737">more lucrative</a>, such that there are few clinicians to deliver cardiac rehab. </p>
<p>Efforts are underway to increase <a href="https://doi.org/10.1097/HCR.0000000000000655">training of health-care professionals to deliver cardiac rehab</a> around the globe. We hope their cardiology systems don’t end up looking like those in high-income settings, with most of the focus and resources on acute care to the neglect of prevention and chronic care.</p>
<p>When we put all these strategies together, the cardiac rehab community can reach and care for the patients who need us most. If you or a loved one have heart disease, ask your doctor for a cardiac rehab referral — it can save your life.</p><img src="https://counter.theconversation.com/content/181234/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Sherry L. Grace has received funding from the Canadian Institutes of Health Research, Heart and Stroke Foundation of Canada, among other international funding agencies to support her research, but has not directly profited from it. She is affiliated with the International Council of Cardiovascular Prevention and Rehabilitation (ICCPR; <a href="https://globalcardiacrehab.com/">https://globalcardiacrehab.com/</a>). </span></em></p>Cardiac rehabilitation is a low-cost approach with proven benefits for heart patients, that drastically lowers future cardiac risks. So why do only 10 to 25 per cent of heart patients access it?Sherry L. Grace, Professor & Sr. Scientist, Faculty of Health, York University, CanadaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1796952022-03-28T11:41:39Z2022-03-28T11:41:39ZPlyometric training: jumping and skipping exercises can help improve strength and fitness<figure><img src="https://images.theconversation.com/files/454650/original/file-20220328-25-pl1ag6.jpg?ixlib=rb-1.1.0&rect=8%2C0%2C5742%2C3837&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Jumping rope is one common form of plyometric training.</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/young-fitness-woman-jumping-rope-home-747150445">Shunevych Serhii/ Shutterstock</a></span></figcaption></figure><p>It’s recommended that <a href="https://www.who.int/publications/i/item/9789240015128">people get 150 minutes</a> of moderate to vigorous physical activity a week. But the part of this advice that people often ignore is that we should do muscle strengthening exercises twice a week. </p>
<p>When we think of muscle strengthening exercises, we often imagine people lifting weights in the gym. But there are actually many ways we can strengthen our muscles that don’t involve going to the gym. For example, carrying food shopping bags in from the car or even walking uphill may both help us build strength.</p>
<p>One way athletes often improve strength and performance is through a method called plyometric training. This includes any exercise that uses jumping, hopping or skipping. The aim of plyometric training is to train the muscles, tendons and nervous system to get better at using their elastic energy. This allows athletes to have faster and more powerful movements that require less muscular effort to perform. So if a sprinter practices plyometric training, they may find it easier to reach their top speed and maintain it during races. </p>
<p>But while we might think plyometric training is a type of exercise only athletes need to do, it may actually have health benefits for everyone – whether you’re a novice or avid exerciser. </p>
<h2>Full-body benefits</h2>
<p>“Explosiveness” – which helps athletes jump higher or sprint a little faster – isn’t the only benefit of plyometric exercises.</p>
<p>Studies have shown plyometric training improves <a href="https://pubmed.ncbi.nlm.nih.gov/18978625">strength, muscle size and muscle speed</a>, alongside <a href="https://pubmed.ncbi.nlm.nih.gov/20836583/">improving coordination</a>. These changes can all lead to <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7931718/pdf/peerj-09-11004.pdf">better athletic performance</a> – from improved jumping, sprinting, strength and even endurance. </p>
<p>And it isn’t just athletes who will benefit from plyometric training. Research shows older adults who perform plyometric exercises (such as vertical jumps) are <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7447006/">better able to jump and climb stairs</a> compared to those who only perform resistance training or walking. It’s also been shown to improve posture, bone health and reduce body fat in <a href="https://link.springer.com/article/10.1007/s40279-018-1018-x">older adults</a>. </p>
<p>In adolescents, <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7463663/">jumping rope</a> (a form of plyometric training) is shown to improve strength, flexibility and bone density. For adults, it can help <a href="https://onlinelibrary.wiley.com/doi/full/10.1111/sms.13487">improve everything</a> from jumping and sprinting ability to lower body strength. It may even improve <a href="https://rjptonline.org/HTMLPaper.aspx?Journal=Research%20Journal%20of%20Pharmacy%20and%20Technology;PID=2019-12-10-46">cardiovascular fitness and flexibility</a> in men and <a href="https://link.springer.com/article/10.1007/s40279-016-0494-0">bone density</a> in women.</p>
<p>Since plyometric exercises help improve coordination, they are also commonly used to help people <a href="https://journals.sagepub.com/doi/full/10.1177/0363546505282619">avoid and recover from injuries</a>.</p>
<h2>What to know</h2>
<p>While plyometric training can be very beneficial, it also has a risk of causing injures if the exercises are performed incorrectly. </p>
<p>In the past, it was suggested people shouldn’t perform plyometric training if they couldn’t squat one and a half times their body weight – alongside being able to balance on one leg in a half-squat position for 30 seconds. This might be relevant for more advanced types of plyometric training such as <a href="https://www.youtube.com/watch?v=AFLthPcyMmk">drop jumps</a> (where you drop off a platform onto one or both legs, and quickly jump back up upon impact) and <a href="https://www.youtube.com/watch?v=quYtoRx87KM">bounding</a> (running with a long, leaping stride). But there are many different types of plyometric training out there, which even beginners can do.</p>
<p>For example, activities such as skipping are lower intensity – so they have less impact on our muscles and bones than other types of plyometric training (such as jogging). Many people probably already do plyometric exercises without realising.</p>
<figure class="align-center ">
<img alt="A group of athletic young people perform box jumps in a gym." src="https://images.theconversation.com/files/454651/original/file-20220328-25-pkfk5q.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/454651/original/file-20220328-25-pkfk5q.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/454651/original/file-20220328-25-pkfk5q.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/454651/original/file-20220328-25-pkfk5q.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/454651/original/file-20220328-25-pkfk5q.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/454651/original/file-20220328-25-pkfk5q.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/454651/original/file-20220328-25-pkfk5q.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Box jumps are a more advanced form of plyometric training.</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/fitness-sport-training-exercising-concept-group-635915837">Syda Productions/ Shutterstock</a></span>
</figcaption>
</figure>
<p>Risk of injury with plyometric training increases with the force on landing – so exercises such as drop jumps and bounding should be avoided until you have more strength. But if plyometric training is done in a way that’s suited to your ability, it has a low risk of injury. </p>
<p>If you want to try plyometric training, there are a few movements you should master to keep your risk of injury low.</p>
<p>First, learn how to land properly. When you land, it should be on a full foot with the ankles, knees and hips bent to absorb force. You can work on this by simply balancing on one leg, then hopping slightly and landing on both. To progress, try balancing on one leg but landing on the opposite leg when you hop. </p>
<p>Once you’ve learned to land, it’s important to learn to jump. Choose an object of suitable height that you feel comfortable to jump up on to – such as a small step – and practise jumping up and using the landing techniques to properly absorb the impact. </p>
<p>When you’ve mastered landing and jumping then you can progress to jumping on the spot repeatedly, such as skipping. Start with two feet at a time and progress to alternate single legs. As you become more confident and competent you can then start to progress the height of the repeated jumps in places – such as squat jumps (performing a squat as normal, but exploding into a jump at the top of the movement) and tuck jumps (similar to a squat jump, but tucking your legs into your chest at the top of your jump). To progress this further, try jumping forwards or sideways. Remember that the main aim of plyometric training is to be elastic. This is why it’s important to aim to be “springy” on all of your jumps. </p>
<p>The most demanding plyometrics are known as shock jumps or depth jumps. These involve dropping off a bench or box (usually over 30 cm) onto the floor and performing an instant jump. These jumps will have high landing forces and should only be performed when you’ve mastered all the other techniques and can do them with confidence.</p>
<p>Plyometric training is a cost-effective, time-efficient form of exercise that can improve your health and fitness. If you want to try plyometric training, aim to do plyometric exercises one to three times a week.</p><img src="https://counter.theconversation.com/content/179695/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>The authors do not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Plyometric training isn’t only for athletes – but there are a few movements beginners will need to master if they want to try it.Lindsay Bottoms, Reader in Exercise and Health Physiology, University of HertfordshireJon Brazier, Senior Lecturer Strength and Conditioning, University of HertfordshireLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1752882022-02-01T21:21:23Z2022-02-01T21:21:23ZThe baffling case of metabolically healthy obese people: Are they protected from chronic diseases?<figure><img src="https://images.theconversation.com/files/443086/original/file-20220127-9640-1k7cbpu.jpeg?ixlib=rb-1.1.0&rect=0%2C276%2C1211%2C783&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Some studies have demonstrated that a significant number of obese people are metabolically healthy, leading to the contention that one could be healthy at any size.</span> <span class="attribution"><a class="source" href="https://www.instagram.com/juliakubow/">(Julia Kubow)</a>, <span class="license">Author provided</span></span></figcaption></figure><iframe style="width: 100%; height: 175px; border: none; position: relative; z-index: 1;" allowtransparency="" src="https://narrations.ad-auris.com/widget/the-conversation-canada/the-baffling-case-of-metabolically-healthy-obese-people--are-they-protected-from-chronic-diseases" width="100%" height="400"></iframe>
<p>There is a growing global body positivity movement to combat the <a href="https://www.euro.who.int/__data/assets/pdf_file/0017/351026/WeightBias.pdf">stigma and prejudice that overweight and obese individuals face</a>. Some of this stigma arises from the perception that obese individuals are unhealthy. </p>
<p>However, weight is only one of the metrics that medical professionals use to assess overall health. In fact, some studies have demonstrated that a significant number of obese people are metabolically healthy, leading to the contention that one could be <a href="https://dx.doi.org/10.2105%2FAJPH.2015.302552">healthy at any size</a>. This phenomenon is referred to as <a href="https://www.mdpi.com/2218-1989/10/2/48">metabolically healthy obesity</a> (MHO). Research is now starting to explore what this means. </p>
<p>A person who is MHO has healthy blood pressure, normal levels of blood lipids (cholesterol and triglycerides) and normal blood sugar. Having high values of one or more of these measures significantly increases one’s risk for cardiovascular disease. </p>
<figure class="align-right ">
<img alt="Illustration of foods representative of the Mediterranean diet: olive oil, seafood, nuts, grains" src="https://images.theconversation.com/files/443864/original/file-20220201-21-obngem.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/443864/original/file-20220201-21-obngem.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=465&fit=crop&dpr=1 600w, https://images.theconversation.com/files/443864/original/file-20220201-21-obngem.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=465&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/443864/original/file-20220201-21-obngem.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=465&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/443864/original/file-20220201-21-obngem.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=584&fit=crop&dpr=1 754w, https://images.theconversation.com/files/443864/original/file-20220201-21-obngem.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=584&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/443864/original/file-20220201-21-obngem.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=584&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Healthy diets provide anti-inflammatory and antioxidant benefits that help achieve a healthy metabolic profile.</span>
<span class="attribution"><span class="source">(Shutterstock)</span></span>
</figcaption>
</figure>
<p>It has been proposed that metabolically healthy obese individuals might be protected against obesity-related diseases. The extent of this protection has been controversial within the scientific community, and this is partly because we still <a href="https://www.karger.com/Article/Fulltext/495852">don’t have a standardized definition of MHO</a>. </p>
<p>So, over the past few years, researchers have gone to work to find out who can be defined as MHO, and to what extent people with MHO are protected from chronic disease. </p>
<h2>Emerging consensus</h2>
<p>Several large population studies have been initiated towards this end. So far, results show that, indeed, more rigorous definitions of MHO are needed. This can be achieved by <a href="https://doi.org/10.1172/JCI129186">including other measures of health</a> such as insulin resistance and blood markers of inflammation. Insulin resistance is when the body does not respond well to the insulin hormone that helps to take up sugar from the bloodstream for use as a fuel for energy. This leads to elevated blood sugar and the consequent health complications.</p>
<p>An emerging consensus has been that although MHO individuals show some protection from chronic disease, they still seem to be significantly less protected than those who are metabolically healthy and lean.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/443629/original/file-20220201-21-t6nwbh.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Infographic showing different combinations of health status and obesity" src="https://images.theconversation.com/files/443629/original/file-20220201-21-t6nwbh.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/443629/original/file-20220201-21-t6nwbh.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=390&fit=crop&dpr=1 600w, https://images.theconversation.com/files/443629/original/file-20220201-21-t6nwbh.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=390&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/443629/original/file-20220201-21-t6nwbh.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=390&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/443629/original/file-20220201-21-t6nwbh.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=490&fit=crop&dpr=1 754w, https://images.theconversation.com/files/443629/original/file-20220201-21-t6nwbh.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=490&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/443629/original/file-20220201-21-t6nwbh.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=490&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Individuals with metabolically healthy obesity have lower risk of disease than those with metabolically unhealthy obesity, but still higher risk than non-obese, metabolically healthy individuals.</span>
<span class="attribution"><span class="source">(Kubow/Iskandar)</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>The fact that people with MHO still have a relatively higher disease risk led some researchers to suggest that the term “metabolically healthy obesity” could be a misnomer. Moreover, <a href="https://doi.org/10.1172/JCI129186">a majority of the MHO population tends to progress towards “metabolically unhealthy obesity” or MUO over a number of years</a>, leading to enhanced risk of diabetes, cardiovascular disease and other disorders linked with obesity. </p>
<p>This leads to another question: is MHO truly protective over an entire lifetime, or is it just a question of time before MUO sets in, making MHO a transient state? </p>
<h2>Protective factors</h2>
<p>One factor to consider that might differentiate metabolically healthy versus unhealthy obesity is how fat is distributed in the body. A <a href="https://doi.org/10.3390/ijms20153690">genetic predisposition for depositing fat under the skin</a>, called subcutaneous fat, seems to play a protective role. </p>
<p>People with this predisposition are mostly premenopausal women who accumulate subcutaneous body fat in the hips rather than the waist (pear-shaped). They are <a href="https://doi.org/10.1016/S2213-8587(19)30084-1">better protected against diabetes and cardiovascular disease</a> compared to people whose body fat is located more in the abdomen (apple-shaped). </p>
<p>In contrast, obese individuals with a high waist circumference show excessive fat deposition in the abdomen and a <a href="https://nutrition.org/inflammation-what-is-it-and-how-can-my-diet-and-behavior-affect-it/">pro-inflammatory</a> state that leads to insulin resistance, which can be a precursor to Type 2 diabetes.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/443863/original/file-20220201-14-4iu6yf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Series of illustrations of a woman in exercise clothes" src="https://images.theconversation.com/files/443863/original/file-20220201-14-4iu6yf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/443863/original/file-20220201-14-4iu6yf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=269&fit=crop&dpr=1 600w, https://images.theconversation.com/files/443863/original/file-20220201-14-4iu6yf.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=269&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/443863/original/file-20220201-14-4iu6yf.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=269&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/443863/original/file-20220201-14-4iu6yf.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=338&fit=crop&dpr=1 754w, https://images.theconversation.com/files/443863/original/file-20220201-14-4iu6yf.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=338&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/443863/original/file-20220201-14-4iu6yf.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=338&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">People with metabolically healthy obesity are involved in regular physical activity to a greater extent than those with metabolically unhealthy obesity.</span>
<span class="attribution"><span class="source">(Shutterstock)</span></span>
</figcaption>
</figure>
<p>Researchers have also looked at the lifestyle habits that differentiate MHO from MUO individuals to see if development of metabolically unhealthy obesity can be prevented. </p>
<p>One factor is exercise. People with MHO are involved in <a href="https://doi.org/10.1016/j.pcad.2018.07.008">regular physical activity to a greater extent than MUO individuals</a>. The other is diet. Although <a href="https://doi.org/10.1172/JCI129186">dietary studies show mixed results</a>, it seems that <a href="https://doi.org/10.3390/nu13113925">MHO people consume healthier diets</a> such as the Mediterranean diet, which is rich in fish, fruits, vegetables, whole-grain products, legumes, extra virgin olive oil and nuts. </p>
<p>Healthy diets provide <a href="https://www.health.harvard.edu/staying-healthy/foods-that-fight-inflammation">anti-inflammatory and antioxidant</a> benefits that help achieve a healthy metabolic profile. Indeed, of the MHO population, those who <a href="https://doi.org/10.1038/ijo.2016.114">follow the Mediterranean diet seem to have lower mortality rates</a>. Adopting these healthy lifestyle habits could help prevent the trajectory of metabolically healthy obesity moving towards metabolically unhealthy obesity over the course of a lifetime. </p>
<h2>Is metabolically healthy obesity real?</h2>
<p>So is MHO real and does it protect against disease? There isn’t a yes or no answer yet. The more we learn about it, the more nuance is injected into the concept that one can be perfectly healthy at any size. Based on the information we have so far, <a href="https://doi.org/10.1038/s41574-021-00619-6">only a narrow segment of obese individuals are without risk</a> of developing obesity-related chronic diseases. </p>
<p>We also know a lot more about their characteristics. They have less abdominal fat and more subcutaneous fat. They have less insulin resistance, less inflammation and a metabolically healthy cardiovascular profile. They also have healthy lifestyle habits such as regular exercise and a healthy diet. It seems that genetics play a role as well. </p>
<p>We can expect more insight from major international population studies and clinical trials that are currently underway. But in the meantime, the age-old advice holds truer than ever: regular physical activity and a healthy diet are crucial to maintain health and longevity.</p><img src="https://counter.theconversation.com/content/175288/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>The authors do not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Some obese people lack the classic metabolic risk factors of high blood pressure, high cholesterol and high blood sugar linked with obesity. But are they still at risk for heart disease and diabetes?Stan Kubow, Associate Professor, School of Human Nutrition, McGill UniversityMichele Iskandar, Research Associate and Lecturer, School of Human Nutrition, McGill UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1751422022-01-24T03:14:46Z2022-01-24T03:14:46ZA healthier heart can protect your brain too. 5 lifestyle changes to prevent dementia<p>When we think of dementia, we often <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5995109/">fear</a> a loss of control. But the reassuring news is up to 40% of dementias can be <a href="https://pubmed.ncbi.nlm.nih.gov/32738937/">prevented or delayed</a> if we change our health habits.</p>
<p>Nearly half a million Australians are <a href="https://www.dementia.org.au/information/statistics/prevalence-data">living with dementia</a>. Without a cure, this number is expected to reach 1.1 million by 2058. </p>
<p>Dementia shares key risk factors with cardiovascular (of the heart and blood vessels) disease, including high blood pressure, high blood sugar, being overweight and smoking. Inflammation and oxidative stress (where protective antioxidants are losing their fight with damaging free radicals) follow. This damages blood vessels and reduces the flow of blood and oxygen to the brain. </p>
<p>Without enough oxygen, brain cells can’t function effectively, and eventually die. Reduced blood flow also leaves the brain vulnerable to the <a href="https://www.alz.org/alzheimers-dementia/what-is-alzheimers/brain_tour_part_2">plaques and tangles</a> seen in forms of dementia.</p>
<p>But by changing our habits, we can both improve heart health and reduce the risk of dementia. Here are five lifestyle changes we can make now … </p>
<h2>1. Eat 2–3 serves of oily fish each week</h2>
<p>Oily fish, like salmon, sardines and mackerel are rich in omega-3 polyunsaturated fatty acids. Omega-3’s have anti-inflammatory effects and have been shown to significantly <a href="https://pubmed.ncbi.nlm.nih.gov/24610882/">reduce blood pressure</a>. </p>
<p>Omega-3s are also needed to support the structure and function of our brain cells and are “essential nutrients”. This means we need to get them from our diet. This is especially true as we age, because reductions in omega-3 intake have been <a href="https://pubmed.ncbi.nlm.nih.gov/28466678/">linked</a> to faster rates of cognitive decline. </p>
<h2>2. Eat plant foods with every meal</h2>
<p>Plant foods – like leafy greens, extra virgin olive oil, blueberries, nuts and pulses - contain a range of vitamins and minerals, including polyphenols, flavonoids, carotenoids, vitamin C and vitamin E. These micronutrients have both <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5456284/">antioxidant and anti-inflammatory effects</a> that protect and improve our blood vessel functioning.</p>
<p>Diets high in plant foods, like the Mediterranean diet, have been shown to improve blood pressure, glucose regulation and body composition, and have also been <a href="https://pubmed.ncbi.nlm.nih.gov/28212320/">linked</a> to lower rates of cognitive decline, better markers of <a href="https://alz-journals.onlinelibrary.wiley.com/doi/abs/10.1002/alz.045349">brain health</a> and <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5015034/">lower risk</a> of dementia.</p>
<h2>3. Eat less processed food</h2>
<p>On the other hand, saturated fats, refined carbohydrates and red and processed meats are <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6269634/">believed to trigger</a> inflammatory pathways and highly processed foods have been linked to <a href="https://pubmed.ncbi.nlm.nih.gov/27927627/">hypertension</a>, <a href="http://ijmpnet.com/journals/ijmp/Vol_8_No_1_June_2020/1.pdf">type 2 diabetes</a> and <a href="https://www.nature.com/articles/s41387-020-00141-0">obesity</a>. </p>
<p>Eating more of these foods means we’re also likely to miss out on the benefits of other foods. Whole grains (like whole oats, rye, buckwheat and barley) provide fibre, vitamin B, E, magnesium and phytonutrients which have anti-inflammatory and antioxidant properties. Refined grains (like white bread, rice and pasta) are highly processed, meaning many of these beneficial nutrients are removed. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/why-people-with-dementia-dont-all-behave-the-same-100960">Why people with dementia don't all behave the same</a>
</strong>
</em>
</p>
<hr>
<h2>4. Get physical and make it fun</h2>
<p>Physical activity can <a href="https://www.ahajournals.org/doi/full/10.1161/HYPERTENSIONAHA.116.08398">reduce inflammation and blood pressure</a>, while improving blood vessel functioning. This helps the body deliver more oxygen to the brain, <a href="https://www.sciencedirect.com/science/article/abs/pii/S0378512219301203">improving memory and other cognitive functions</a> affected by dementia. </p>
<p>Guidelines suggest adults should engage in physical activity on most days, break up long bouts of inactivity (like watching TV) and incorporate some resistance exercises.</p>
<p>The key to forming long-term exercise habits is choosing physical activities you <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3646077/">enjoy</a> and making small, <a href="https://pubmed.ncbi.nlm.nih.gov/26857881/">gradual increases</a> in activity. Any movement that raises the heart rate can be classified as physical activity, including gardening, walking and even household chores.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/aiming-for-10-000-steps-it-turns-out-7-000-could-be-enough-to-cut-your-risk-of-early-death-167447">Aiming for 10,000 steps? It turns out 7,000 could be enough to cut your risk of early death</a>
</strong>
</em>
</p>
<hr>
<h2>5. Quit smoking</h2>
<p>Smokers are <a href="https://pubmed.ncbi.nlm.nih.gov/32738937/">60% more likely to develop dementia</a> than non-smokers. This is because smoking increases inflammation and oxidative stress that harm the structure and function of our blood vessels.</p>
<p><a href="https://www.cancercouncil.com.au/cancer-prevention/smoking/quitting-smoking/">Quitting smoking</a> can begin to reverse these effects. In fact, former smokers have a significantly <a href="https://pubmed.ncbi.nlm.nih.gov/30349854/">lower risk of cognitive decline and dementia</a> compared to current smokers, similar to that of people who have never smoked.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/covid-19-has-offered-us-an-unexpected-opportunity-to-help-more-people-quit-smoking-146747">COVID-19 has offered us an unexpected opportunity to help more people quit smoking</a>
</strong>
</em>
</p>
<hr>
<h2>Is it too late?</h2>
<p>It’s never too early, or too late, to begin making these changes. </p>
<p>Obesity and high blood pressure in midlife are key predictors of dementia risk, while diabetes, physical inactivity and smoking are stronger predictors later in life. Regular physical activity earlier in life can reduce blood pressure and decrease your risk of diabetes. Like giving up smoking, changes at any stage of life can reduce inflammation and change your dementia risk. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/442123/original/file-20220124-21-1yd61jt.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="brains scans" src="https://images.theconversation.com/files/442123/original/file-20220124-21-1yd61jt.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/442123/original/file-20220124-21-1yd61jt.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/442123/original/file-20220124-21-1yd61jt.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/442123/original/file-20220124-21-1yd61jt.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/442123/original/file-20220124-21-1yd61jt.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/442123/original/file-20220124-21-1yd61jt.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/442123/original/file-20220124-21-1yd61jt.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">PET scans show the brain changes seen in Alzheimer’s disease, the most common form of dementia.</span>
<span class="attribution"><a class="source" href="https://photos-cdn.aap.com.au/Image/20180410001341633387?path=/aap_dev9/device/imagearc/2018/04-10/80/17/9b/aapimage-6znbjhqxi15mvg4kp3i_layout.jpg">AP Photo/Evan Vucci</a></span>
</figcaption>
</figure>
<h2>Little by little</h2>
<p>It can be overwhelming to change your whole diet, start a new exercise program and quit smoking all at once. But even small changes can lead to significant improvements in health. Start by making manageable swaps, like:</p>
<ul>
<li> use extra virgin olive oil in place of butter, margarine and other cooking oils</li>
<li> swap one serve of processed food, like chips, white bread, or commercial biscuits, for a handful of nuts</li>
<li> swap one serve of meat each week for one serve of oily fish</li>
<li> swap five minutes of sedentary time for five minutes of walking and slowly increase each day.</li>
</ul><img src="https://counter.theconversation.com/content/175142/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Ashleigh Elizabeth Smith receives funding from the National Health and Medical Research Council (NH&MRC) and the Hospital Research Foundation. </span></em></p><p class="fine-print"><em><span>Maddison Mellow receives funding from the Dementia Australia Research Foundation (PhD scholarship). </span></em></p><p class="fine-print"><em><span>Alexandra Wade does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>Heart health is strongly linked to brain health and risk of dementia. That means improving one can protect us from the other.Alexandra Wade, Research associate, University of South AustraliaAshleigh E. Smith, Senior Lecturer - Exercise Physiology, University of South AustraliaMaddison Mellow, PhD candidate, University of South AustraliaLicensed as Creative Commons – attribution, no derivatives.