tag:theconversation.com,2011:/au/topics/100m-dash-107445/articles100m dash – The Conversation2021-07-21T19:27:14Ztag:theconversation.com,2011:article/1628322021-07-21T19:27:14Z2021-07-21T19:27:14ZAre middle lanes fastest in track and field? Data from 8,000 racers shows not so much<figure><img src="https://images.theconversation.com/files/411575/original/file-20210715-32740-t68wyj.jpg?ixlib=rb-1.1.0&rect=0%2C123%2C5150%2C3299&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The fastest runners are usually rewarded with the middle lanes. </span> <span class="attribution"><a class="source" href="https://www.gettyimages.com/detail/photo/male-athltes-starting-from-blocks-on-track-royalty-free-image/457893067?adppopup=true"> Michael H/Stone vie Getty Images</a></span></figcaption></figure><p>As a short-distance track and field runner in high school and college, I often found myself wondering which of the eight or sometimes nine lanes on the track was the fastest. It was conventional wisdom that the middle lanes – lanes three through six – were the best.</p>
<p>This idea, in a way, is baked into the rules of track and field. In events with multiple heats – from the <a href="http://www.ncaapublications.com/p-4623-2021-2022-cross-country-and-track-and-field-rules.aspx">college level</a> all the way to the <a href="https://www.worldathletics.org/about-iaaf/documents/book-of-rules">Olympics</a> – the people who run faster times in earlier heats are assigned to middle lanes in later heats. In other words, the fastest runners are rewarded with what are, supposedly, better lane assignments. </p>
<p>My short-lived track career is long behind me, but in my <a href="http://www.middlebury.edu/academics/econ/faculty_staff_officehours/node/538091">professional life as an economist</a>, I think a great deal about using statistics to extract meaning from data. With the Olympics on my mind, I decided to examine the validity of lane assignment folklore from my days as a sprinter. </p>
<p>Using 20 years of track and field data from the <a href="https://www.worldathletics.org/">International Association of Athletics Federations</a>, I found that the long-held beliefs about lane advantages are not supported by the <a href="https://papers.ssrn.com/sol3/papers.cfm?abstract_id=3801883">data</a>. And in fact, for the 200-meter sprint, the evidence suggests that lanes often perceived as the least desirable are actually the fastest.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/411576/original/file-20210715-15-137tynv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Runners in a staggered spacing coming around a turn." src="https://images.theconversation.com/files/411576/original/file-20210715-15-137tynv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/411576/original/file-20210715-15-137tynv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=358&fit=crop&dpr=1 600w, https://images.theconversation.com/files/411576/original/file-20210715-15-137tynv.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=358&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/411576/original/file-20210715-15-137tynv.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=358&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/411576/original/file-20210715-15-137tynv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=450&fit=crop&dpr=1 754w, https://images.theconversation.com/files/411576/original/file-20210715-15-137tynv.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=450&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/411576/original/file-20210715-15-137tynv.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=450&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Tighter turns and staggered starting positions supposedly make inside and outside lanes slower.</span>
<span class="attribution"><a class="source" href="https://commons.wikimedia.org/wiki/File:Crawford,_Dzingai_200_m_Berlin_2009.jpg#/media/File:Crawford,_Dzingai_200_m_Berlin_2009.jpg">André Zehetbauer/WikimediaCommons</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<h2>Myth of the middle lane</h2>
<p>If lane assignments do matter, their impact would be most noticeable for events where the runners have to stay in their lanes for all of, or at least a large part of, the race, like 100-meter, 200-meter, 400-meter and 800-meter events. </p>
<p>In my experience, the myth of the middle lane being the fastest is most commonly associated with fast-paced races that also include corners, so the 200 and 400. There are two rationales behind this point of view, and they have to do with why the inside and outside lanes are bad, more than why middle lanes are better. </p>
<p>The reasoning for why inside lanes are bad is that in races with turns, the inside lanes are slower because the corners are too tight. Indeed, researchers who study the biomechanics of running find that tighter corners do <a href="https://doi.org/10.1242/jeb.133488">slow runners down</a>.</p>
<p>The rationale behind slow outside lanes has to do with the <a href="https://www.sbnation.com/2016/8/15/12486250/rio-2106-track-athletics-lane-staggered-start-400-record-wayde-van-niekerk">staggered starts</a> required to make sure each racer runs the same distance. Due to this staggering, runners in the outside lanes cannot see their competitors for the majority of the race. The thinking goes that outside runners may have <a href="https://www.sbnation.com/2016/8/15/12486250/rio-2106-track-athletics-lane-staggered-start-400-record-wayde-van-niekerk">less motivation to chase competitors</a> or have <a href="https://www.livescience.com/55768-track-outside-lanes-olympic-running-swimming.html">difficulty gauging their speed</a> compared to the pack if they can’t see other racers.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/411577/original/file-20210715-32887-6l8zkl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="Racers at the starting blocks of a 200m sprint." src="https://images.theconversation.com/files/411577/original/file-20210715-32887-6l8zkl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/411577/original/file-20210715-32887-6l8zkl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=399&fit=crop&dpr=1 600w, https://images.theconversation.com/files/411577/original/file-20210715-32887-6l8zkl.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=399&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/411577/original/file-20210715-32887-6l8zkl.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=399&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/411577/original/file-20210715-32887-6l8zkl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=501&fit=crop&dpr=1 754w, https://images.theconversation.com/files/411577/original/file-20210715-32887-6l8zkl.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=501&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/411577/original/file-20210715-32887-6l8zkl.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=501&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">In the 200-meter sprint, where racers have a staggered start and go around one turn, the outside lane seems to be the fastest.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/nickwebb/7734445082/in/set-72157630789298326">Nick Webb/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<h2>Not all lanes are the same</h2>
<p>In most races, the <a href="https://www.worldathletics.org/about-iaaf/documents/book-of-rules">fastest runners are assigned to the middle lanes</a> in accordance with the competition rules. Not surprisingly, the fastest runners – who are in the middle lanes – often win. Are these racers winning because those lanes are the fastest or because those runners tend to be the fastest? </p>
<p>Similar to the idea behind clinical trials for a drug, the ideal way to test lane advantages would be to randomly assign runners to lanes and see how they do on average. Thankfully, there is a subset of race data that does this: Typically, runners are randomly assigned to lanes in the first heats of events. By using data only from first heats of elite track and field events, I was able eliminate the bias from faster runners being assigned to certain lanes. </p>
<p>Using roughly 8,000 individual race results, I found that the “middle is best” belief is not well supported by the data.</p>
<p>For the 100 – which is run on a straightaway – I found no evidence of lane advantages. The myth is less prevalent here, though, so this lack of difference isn’t surprising.</p>
<p>The most striking counterpoint to the “middle is best” assumption is the 200. I found that it is in fact outside lanes that are associated with faster race times – on average lane eight is roughly 0.2 seconds faster than lane two. This is sizable for a race in which the <a href="https://www.worldathletics.org/records/by-discipline/sprints/200-metres/outdoor/men">world record is 19.19 seconds</a>. Faster outside lanes make sense biomechanically as tighter corners produce slower race times. But the result seems to disprove the idea that not seeing competitors can slow a runner down.</p>
<p>In the 400, I found no evidence that middle lanes are fastest. All lanes seem to be roughly equal. It is worth noting that there is more variability in 400-meter times, so it is harder to detect small effects, if they exist. But even this nondifference between lanes in the 400 is striking. </p>
<p>In the 2016 Olympics, people <a href="https://www.bbc.com/news/newsbeat-37083059">marveled when Wayde Van Niekerk won the 400 final from lane eight</a>, the farthest outside lane. The astonishment stemmed from the belief that lane eight puts runners at a disadvantage. The data doesn’t support this. But what is impressive about Van Niekerk’s win is that he was one of the slower runners to qualify for the final – that’s why he was assigned to one of the “least desirable” lanes. </p>
<p>The last event I looked at, the 800, is distinct from the other events above. It has what is called a “lane break,” which is where runners must remain in their assigned lanes for the first 100 meters but are then free to run in any lane they wish. Since the inside lane of a track covers the shortest distance, runners in outside lanes move inward after the break. As they do this, they may have to run a tiny bit farther than their competitors and jockey for position with runners who are already in the inside lanes. I found that racers who start at the very inside lanes ran the fastest times. While outside lanes might have a small advantage over the first 100 meters, runners who have an established position on the inside of the track seem to have an overall advantage. </p>
<p>Next time you’re watching any of the shorter track and field events at the Olympics, listen to see if anyone repeats the old adage that the middle lanes are fastest. The data says this isn’t true, so if someone in the outside lanes takes a surprise gold, you’ll know to be surprised not because of their lane assignment, but because they were a slow qualifier.</p>
<p>[<em>Insight, in your inbox each day.</em> <a href="https://theconversation.com/us/newsletters/the-daily-3?utm_source=TCUS&utm_medium=inline-link&utm_campaign=newsletter-text&utm_content=insight">You can get it with The Conversation’s email newsletter</a>.]</p><img src="https://counter.theconversation.com/content/162832/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>David R. Munro 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>In track and field, it’s a common belief that middle lanes are the fastest. But according to the data, middle lanes aren’t better, and in the 200-meter sprint, outside lanes might even be faster.David R. Munro, Assistant Professor of Economics, MiddleburyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/640742016-08-19T21:29:25Z2016-08-19T21:29:25ZWhat food does it take to fuel athletes like Usain Bolt to Olympic success?<p>Usain Bolt <a href="http://www.bbc.co.uk/sport/olympics/36690965">made history</a> at the Rio Olympics, becoming the first athlete to win gold in the 100 metre and 200 metre sprints at three consecutive games. He <a href="http://www.independent.co.uk/sport/olympics/rio-2016-usain-bolt-angry-world-record-200m-gold-medal-a7198746.html">didn’t beat his world record</a> of 9.58 seconds, but still managed to leave his competitors for dust. </p>
<p>It takes years of intense training and enormous discipline for athletes such as Bolt to achieve their Olympic dreams – and throughout it all they have to adhere to strict dietary requirements. To find out what sort of food it takes to fuel Bolt’s Olympic efforts, it’s worth taking a closer look at an Olympic sprinter’s ideal diet.</p>
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<p>In the run up to the Olympic Games, Bolt would actually require more energy than during the games themselves. High quality preparatory training sessions use up a huge number of calories which need to be replaced with the correct nutrients. After all, these sessions are crucial in giving Bolt the all-important muscle power and technique that help him to gain the advantage over his competitors.</p>
<h2>Protein over carbo-loading</h2>
<p>During training, sprinters have to maintain a nourishing and balanced diet. This is predicated on the familiar mix of protein, carbohydrate, vitamins and minerals. Unlike some endurance athletes, sprinters don’t need to <a href="https://theconversation.com/carbo-loading-for-sport-is-simple-when-you-know-how-8071">carbo-load</a> with bread, potatoes, rice, pasta and cereals. Instead, protein – found in eggs, meat, fish, nuts, beans and dairy products – is perhaps the key dietary requirement. Protein allows muscles to recover, repair and develop after sprint and resistance drills which cause minute damages to the muscle fibres. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/134765/original/image-20160819-30377-x9kvyu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/134765/original/image-20160819-30377-x9kvyu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=372&fit=crop&dpr=1 600w, https://images.theconversation.com/files/134765/original/image-20160819-30377-x9kvyu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=372&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/134765/original/image-20160819-30377-x9kvyu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=372&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/134765/original/image-20160819-30377-x9kvyu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=467&fit=crop&dpr=1 754w, https://images.theconversation.com/files/134765/original/image-20160819-30377-x9kvyu.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=467&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/134765/original/image-20160819-30377-x9kvyu.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=467&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Another piece of chicken?</span>
<span class="attribution"><span class="source">Elena Schweitzer/Shuttertock</span></span>
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</figure>
<p>Carbohydrates are still crucial for sprinters as sprint training also uses up a huge amount of a compound called glycogen. When we eat carbohydrate, it is broken down and stored by the body in the muscles and liver <a href="https://www.sciencedaily.com/terms/glycogen.htm">in the form of glycogen</a>. Sprint training can deplete glycogen stores very quickly since it’s the only fuel available to the body at such high intensity effort. Bolt’s 100 metre world record time of 9.58 seconds isn’t long enough for the body to process the oxygen it needs and so energy is provided anaerobically – without oxygen – from fuels already found in the muscles.</p>
<p>The all out effort of sprinting can use up most, if not all, of the glycogen stored in the body. During a training session, if Bolt is doing repeated sprints of 20 to 50 metres, the majority of his muscles’ glycogen <a href="http://www.faqs.org/sports-science/Fo-Ha/Glycogen-Depletion.html">will be depleted</a> after about eight to ten efforts. Good nutrition is therefore vital to restock the lost glycogen and repair any routine muscular damage that’s been done.</p>
<p>When the Olympic Games draws closer – and with the bulk of athletes’ training behind them – their energy requirements lessen and they look to simply maintain their weight. The good news for sprinters is that there’s a reasonable amount of flexibility with what they can eat the night before a medal race. Apart from adhering to the basic principals of a balanced diet, the main recommendations are to limit fibre intake and to avoid a high-fat meal – which can lie heavily in the stomach. Athletes should also stick to familiar dishes to avoid upsetting their digestion with food that they’re not used to the night before a race. Trying local delicacies is best left until after the games have finished. </p>
<p>Rest assured, however, that there is some wriggle room, even in the diet of a world class sprinter. If Bolt’s <a href="http://www.independent.co.uk/sport/general/athletics/usain-bolt-reveals-he-devoured-1000-chicken-mcnuggets-during-the-2008-beijing-olympics-8920870.html">fabled love of chicken nuggets</a> is indeed true, then he wouldn’t have to constantly deprive himself of his favourite snack. Although eating fried food every day would cause an excess of fat in the diet, the energy demands on athletes are so high during full training that they can get away with more sweet treats and slightly more fat than the average person. So Bolt can afford to indulge as an occasional luxury, and if he’s just won a gold medal, he certainly deserves it. </p>
<p>And although sprinters are recommended to have a slightly higher protein intake for repair and growth than the general population, Bolt’s diet is not fundamentally different to what an average person should be ideally looking to eat, except of course energy requirements would be higher. Most people should eat a well balanced mix of carbohydrates: pasta, bread, cereals and potatoes, and protein foods: meat, fish, cheese, egg and milk, beans and pulses as well as plenty of vitamin loaded fruit and vegetables. And there’s even room for the occasional indulgence, although the rest of us might not have quite as good an excuse as Bolt for a high-fat binge. </p>
<hr>
<p><em>This article was based on a segment from episode four of <a href="https://theconversation.com/uk/podcasts/the-anthill">The Anthill</a>, a podcast from The Conversation on the subject of fuel. <a href="https://theconversation.com/anthill-4-fuel-64021">Click here</a> to listen to the full episode.</em></p><img src="https://counter.theconversation.com/content/64074/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Emma Kinrade 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>No carb-loading necessary …Emma Kinrade, Lecturer in Dietetics, Glasgow Caledonian UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/629762016-08-15T07:12:23Z2016-08-15T07:12:23ZWhat makes a winning sprinter?<p>In all sprint running races (100m to 400m), every hundredth of a second gained or lost in the race counts. But, most importantly, the fastest male and female sprinters attain incredible top running speeds, <a href="https://www.youtube.com/watch?v=SyY7RgNLCUk">with peaks in excess of 44km per hour</a> and 38km per hour in the men’s and women’s 100m races, for example. So what makes a fast runner?</p>
<p>The fastest sprinters on average take longer strides than slower sprinters, but at a <a href="http://www.ncbi.nlm.nih.gov/pubmed/1615256">similar stride rate</a>. This results from larger forces being delivered to the ground in the short foot-ground contact period (often 0.1 second). </p>
<p>Of course, having longer legs can <a href="http://www.ncbi.nlm.nih.gov/pubmed/23717364">benefit stride length</a>, which appears to be a significant <a href="http://www.meathathletics.ie/devathletes/pdf/Biomechanics%20of%20Sprints.pdf">reason for Usain Bolt’s superior top speed</a>. </p>
<h2>Generating force</h2>
<p>In addition to improving stride length, the greater distance of the foot from the hip in taller sprinters allows a faster backwards horizontal foot speed to be attained for a given hip angular velocity, since the foot velocity (v) is a function of hip angular velocity (ω) and hip-foot distance (r); v = ωr.</p>
<p>But it’s not all good news for taller runners. Longer limbs have a greater moment of inertia (they’re harder to move), so they’re accelerated less for a given hip torque production (i.e. muscle force). </p>
<p>In this case, there are different costs-benefits for shorter versus taller sprinters; shorter sprinters must attain faster limb movement speeds, but taller sprinters need to generate sufficient torque to rapidly accelerate their longer limbs.</p>
<p>It’s also clear that rapid force production is paramount. Peak <a href="http://www.ncbi.nlm.nih.gov/pubmed/18317373">forces of more than 2500N</a> (255kg) are delivered to the ground within a few hundredths of a second in each step.</p>
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<a href="https://images.theconversation.com/files/132751/original/image-20160802-17165-1qrd3py.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/132751/original/image-20160802-17165-1qrd3py.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/132751/original/image-20160802-17165-1qrd3py.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/132751/original/image-20160802-17165-1qrd3py.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/132751/original/image-20160802-17165-1qrd3py.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/132751/original/image-20160802-17165-1qrd3py.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/132751/original/image-20160802-17165-1qrd3py.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/132751/original/image-20160802-17165-1qrd3py.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"></a>
<figcaption>
<span class="caption">Ground forces during sprint running. Faster sprinters (black line) produce greater forces in a shorter time (often <0.1s) than slower sprinters (grey line). The ability to produce large forces rapidly against the ground is a key to successful sprinting.</span>
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<p>If we continued to produce such rates of force for just one second, we could accelerate a Forumula 1 car to 100km per hour, or an 80kg athlete to about 900km per hour. Of course, peak force potential is limited in humans, so we won’t see this in Rio.</p>
<h2>Muscular design</h2>
<p>To deliver such forces, we might expect that sprinters possess a unique muscular design, and there is some evidence for this. Better sprinters have a <a href="http://www.ncbi.nlm.nih.gov/pubmed/129449">high proportion of type II muscle fibres</a>, which can develop forces so rapidly that they’re commonly called “fast twitch” fibres. </p>
<p>Further, some important power-producing muscles in their calf and thigh regions may possess <a href="http://www.ncbi.nlm.nih.gov/pubmed/10710372">longer muscle fibre bundles</a> (which is thought to contribute to faster muscle-shortening speeds) attaching at <a href="http://www.ncbi.nlm.nih.gov/pubmed/10710372">smaller angles to the tendon</a> than slower runners.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/133617/original/image-20160810-18014-1jo9xuz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/133617/original/image-20160810-18014-1jo9xuz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/133617/original/image-20160810-18014-1jo9xuz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/133617/original/image-20160810-18014-1jo9xuz.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/133617/original/image-20160810-18014-1jo9xuz.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/133617/original/image-20160810-18014-1jo9xuz.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/133617/original/image-20160810-18014-1jo9xuz.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/133617/original/image-20160810-18014-1jo9xuz.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"></a>
<figcaption>
<span class="caption">In this ultrasound image of the vastus lateralis, a lateral thigh muscle, the muscle fibre bundles can be seen to run at an angle (dotted line denotes the fibre direction at one part of the muscle) to the muscle’s shortening direction (arrow). Sprinters tend to have longer fibres that attach, in this muscle at least, at smaller angles to the muscle-shortening direction. This is believed to improve the high-speed shortening of the muscle.</span>
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<p>But, perhaps paradoxically, the best sprinters don’t have super-sized muscles.</p>
<p>One reason is that even the fastest muscles produce forces too slowly to allow humans to come close to the fast running speeds required, and increasing their size doesn’t help them produce forces any faster.</p>
<p>Instead, muscular forces stretch elastic tissues, such as tendons, and stored energy is subsequently recaptured at much faster rates when they recoil. Because of this, tendons work as “<a href="http://www.ncbi.nlm.nih.gov/pubmed/21228194">power amplifiers</a>”. </p>
<p>However, we know little about the effect of changing tendon properties. We do know that sprint runners have <a href="http://www.ncbi.nlm.nih.gov/pubmed/17101142">stiffer Achilles tendons</a> than non-runners. This should allow them to cope better with forces of over <a href="http://www.ncbi.nlm.nih.gov/pubmed/1638639">900kg placed on the tendon</a> and to recoil faster while under load during the propulsion phase of the foot-contact phase. </p>
<p>We also know that exercise such as <a href="http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4535734/">strength training tends to increase</a> their stiffness while detraining reduces it. </p>
<p>But we don’t yet know what the optimum stiffness is for the Achilles tendon (or other tendons), and we can’t yet set training programs to optimise them.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/132754/original/image-20160802-17198-1gc8hrv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/132754/original/image-20160802-17198-1gc8hrv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/132754/original/image-20160802-17198-1gc8hrv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/132754/original/image-20160802-17198-1gc8hrv.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/132754/original/image-20160802-17198-1gc8hrv.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/132754/original/image-20160802-17198-1gc8hrv.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/132754/original/image-20160802-17198-1gc8hrv.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/132754/original/image-20160802-17198-1gc8hrv.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Before foot-ground contact (left panel) the muscle (pink) and tendon (spring) are relatively inactive. During ground contact, the joints are flexed and muscles highly active (red). Tendons and other elastic structures are stretched and store energy. As the leg extends behind the athlete during propulsion (right panel), muscle shortening is accompanied by tendon recoil, allowing for high rates of force production.</span>
</figcaption>
</figure>
<h2>Getting a move on</h2>
<p>Another issue is that increased muscle mass increases limb inertia (in much the same way as greater limb lengths do), so reducing the acceleration for a given joint torque production. </p>
<p>The best sprinters therefore have very low limb masses, which enables them to cyclically move their arms and legs at high speeds. So, the <a href="http://www.ncbi.nlm.nih.gov/pubmed/21916672">leanest sprinters may be the fastest</a>.</p>
<p>Of final note is that sprinters must deliver their large forces to the ground in a <a href="http://www.ncbi.nlm.nih.gov/pubmed/22422028">very specific direction</a> and with the least wasted energy. They spend years learning techniques that minimise unnecessary limb movements, particularly those in the frontal and transverse planes (those that are not in the direction of running). </p>
<p>The sprinters at the front in the finals will surely display better running techniques.</p>
<p>So while you might not be able to pick the fastest sprinters through muscle fibre type, fibre bundle length, or tendon stiffness tests, you can be sure their limb masses will be small and their techniques will be the most efficient. And after the races are over, perhaps we’ll be able to answer the final question: long legs or short?</p><img src="https://counter.theconversation.com/content/62976/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Anthony Blazevich 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>The fastest male and female sprinters attain incredible top running speeds with peaks in excess of 44km per hour and 38km per hour, respectively, in the men’s and women’s 100m races.Anthony Blazevich, Professor of Biomechanics, Edith Cowan UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/637322016-08-12T08:47:21Z2016-08-12T08:47:21ZThe maths behind the fastest person on Earth (and no it’s not Usain Bolt)<p>Who is the fastest man on Earth? Usain Bolt, right? Wrong. The unpopular answer is, in fact, Justin Gatlin. In 2011, he ran the 100 metres in 9.45 seconds, the fastest time a human has ever run that distance, smashing Usain Bolt’s best time by a massive 0.13 seconds. </p>
<p>At the time, the controversial US athlete – <a href="http://www.bbc.co.uk/sport/athletics/34060181">twice banned from competing for drug-related offences</a> – was being pushed along the track by a huge 20 metre-per-second tail wind (the limit for a time to be ratified as a record is +2m/s). The wind was generated by a number of giant fans as part of a <a href="http://www.mirror.co.uk/sport/row-zed/justin-gatlin-beats-usain-bolts-7468931">Japanese game show</a>, so the “record” didn’t count. Nevertheless, no-one has ever been recorded to run faster from a stationary start on the flat – although some sub-world record times have also been clocked for <a href="https://www.youtube.com/watch?v=a1sO7moXC-s">people running down hill</a>.</p>
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<p>Wind assistance improves athletes’ performances only in these short sprinting events and some of the field events, such as long jump, triple jump, which require sprints in a single direction. For most other track athletes, wind is anathema.</p>
<h2>You wind some, you lose some</h2>
<p>When Roger Banister looked out of the window on the morning of May 6 1954, for example, he almost decided to postpone his attempt to break the four-minute mile record <a href="http://news.bbc.co.uk/onthisday/hi/dates/stories/may/6/newsid_2511000/2511575.stm">because it was too windy</a>. Just before the event, however, the winds dropped enough for him to want to take part and the rest is history. He knew what mathematics can prove: that if you have to do at least one lap of the track, then wind, no matter how light, will always slow you down.</p>
<p>Consider a wind blowing up the home straight of a standard 400 metre athletics track. When Mo Farah runs with the wind, his speed is increased by a set amount, but when he runs against it on the back straight the wind decreases his speed by the same amount. It seems reasonable that these two effects might balance each other out giving Farah the same lap time as if there were no wind at all. Strangely, however, it doesn’t work out that way.</p>
<p>The reason, in essence, is that because you run faster down the home straight, you derive the benefit of being pushed by the wind for only a short time. When you run down the back straight, however, you spend longer going slower, fighting against the wind. The difference in the time you spend being assisted by the wind versus the time you spend battling it ensures your lap time always slows. Imagine the extreme example of a wind so strong that it doubles your speed down the home straight. On the back straight, however, it would reduce your speed to zero meaning that you’d never finish the race.</p>
<p>So wind and other adverse weather conditions can act as a leveller, adding to the uncertainty about the results of individual races. Surely, though, whatever the weather, one thing we can be confident about is that the world’s fastest sprinter will always be a man? <a href="http://news.bbc.co.uk/1/hi/uk/3702650.stm">Well, perhaps not</a>. Researchers from the University of Oxford found that, although 100 metres’ times for both men and women have been decreasing linearly over the years, the women’s time was decreasing at a much faster rate than than the men’s.
The team concluded that, if trends continue as they have over the last 90 years, <a href="http://www.nature.com/news/2004/040927/full/news040927-9.html">women could be dominating the 100 metres by 2156</a>.</p>
<p>However, sports scientists have been critical of the findings and have suggested that increased participation and training opportunities for women over the same time period have led to the artificially rapid reduction in their 100 metre times in comparison to the men’s. They argue that now men and women are on a roughly level playing field the decrease in women’s 100 metre times will begin to slow to a rate comparable with that of the men. Critics also cite fundamental difference in men’s and women’s physiology, <a href="http://www.nature.com/news/2004/040927/full/news040927-9.html">including oxygen carrying capacity and body fat levels</a>, which suggest that the “fastest person on earth” will never be a woman.</p>
<h2>The fastest race</h2>
<p>In fact, although billed as the race for the fastest person on Earth, it’s questionable whether the 100 metres always produces the fastest performance. When Bolt set two new world records for the 100 metres and 200 metres at the 2008 Bejing Olympics in the bird’s nest stadium, his 200 metres took him 19.30 seconds, less than twice the time of his 9.69 second 100 metres. This means that on average, he was running faster in the longer event. </p>
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<p>Part of this increase, however, is due to not having to react and accelerate up to speed in the second 100 metres of the 200 metre race. Based on average speed over the whole race, the title of “fastest person on earth” has switched back and forth between 100 and 200 metre runners since the records began. </p>
<p>This effect is even more exaggerated in the 4x100 metre relay in which all but one of the runners begins their 100-metre stretch from a running start. In the last leg, the “anchor” doesn’t even have to worry about passing on the baton at the other end so can achieve some incredibly quick times. Several sub-nine second times have been recorded in this leg of the race including Bolt’s <a href="http://www.alltime-athletics.com/m4x100ok.htm">electronically-timed 8.65 seconds in 2014</a>.</p>
<p>Despite this, the <a href="https://www.youtube.com/watch?v=SyY7RgNLCUk">fastest human footspeed</a> was recorded between 60 and 80 metres in Bolt’s world record 9.58-second 100 metres in Berlin. He was clocked at <a href="https://www.google.co.uk/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&uact=8&ved=0ahUKEwiGv-GIx7bOAhUkAsAKHVBYCSIQFggjMAA&url=https%3A%2F%2Fwww.iaaf.org%2Fdownload%2Fdownload%3Ffilename%3D76ade5f9-75a0-4fda-b9bf-1b30be6f60d2.pdf%26urlslug%3D1%2520-%2520Biomechanics%2520Report%2520WC%2520Berlin%25202009%2520Sprint%2520Men&usg=AFQjCNEDtoC5EopOC8khd78hdvqowCT0iw&sig2=hDooBLWS4NVhe3M5eD62Gw">44.64kph or 27.8mph</a>.</p>
<p>So despite Gatlin’s “record”, the <em>official</em> “fastest man on Earth” title still rests with Bolt – at least for now.</p><img src="https://counter.theconversation.com/content/63732/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Christian Yates 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>… and how wind played its part.Christian Yates, Lecturer in Mathematical Biology, University of BathLicensed as Creative Commons – attribution, no derivatives.