Feeling sluggish? Grouchy even? Difficulties getting out of bed? Mondayitis can happen to the best of us. But rest assured: it’s a phenomenon science can actually explain.
In fact, there are a range of explanations: perhaps you hate your job and/or are bullied at work; or maybe you live it large at the weekends and come down with a crash on Mondays.
But perhaps the most common cause involves our body clock – i.e. our circadian rhythms – and how our weekend sleeping habits throw our normal rhythms out of whack.
As Sally Ferguson of the University of South Australia explained in a recent article for The Conversation, your circadian rhythm is your “natural pacemaker”. It controls a range of bodily cycles including the 24-hour cycle that regulates your degree of alertness at various times of day.
Normally, our rhythm helps sustain our wakefulness until the end of the day and sustain our sleep until we’re ready to arise in the morning.
The above image shows how the normally-timed circadian “bed” (approximately 11pm to 7am) is surrounded by periods of low sleepiness (or alertness): this is also known as the “sleep forbidden zone” and the “wake-up zone”.
In both, your body “wants” you to be awake: in the “sleep forbidden zone” you’ll find it hard to get to sleep, and in the “wake-up zone”, your body will “try” to wake you up.
If the timing of your body clock changes – by partying till the wee hours, for example – these two zones can shift, making it harder to get to sleep at certain hours.
In practice, this means that if you stay up a couple of hours later than normal one night, the “sleep forbidden zone” will drift to between 8pm and midnight, making it very difficult to get to sleep until after midnight.
If this drifting occurs when it is necessary to get up early – e.g. on weekdays – you’ll lose sleep and be tired the next day.
If this happens most days of the week, you’ll build up a sleep debt over the week that you will probably want to “pay off” when you have the opportunity to do so – on the weekend for most of us.
Sleep-in, and pay the price
How do you catch up on sleep on the weekend? You could go to bed earlier on Friday or Saturday night or you could sleep in later on Saturday and Sunday mornings. Ah, the luxury of the weekend sleep-in! Isn’t that what weekends are for?
Unfortunately, though, that long-awaited weekend lie-in can cause problems come Monday.
By sleeping in, you actively delay your body clock again, which can make it hard to get to sleep on Sunday night and leave you not feeling properly awake until later on Monday morning.
I don’t like Mondays (tell me why!)
Thanks to your weekend lie-in(s), your circadian rhythms have drifted away from their normal position and so, when that alarm clock starts bleating, you’re still at your lowest body temperature (see image above).
You are expected to be up and out into the world while still in your “circadian bed”.
Sure, you’ll probably feel better by noon with the help of the circadian “wake-up zone” (and maybe a stiff coffee or two) but the bad start to Monday has put you behind and you spend the rest of the week in catch-up mode.
This vicious cycle is a problem for many, particularly “night owls” whose rhythms are delayed even more than normal.
So what can be done?
Minimising the number of late bedtimes you have is a good start, as this will reduce your need for catch-up sleep.
And if you do need to have catch-up sleep on the weekend, don’t sleep in late: get up about the same time you normally would and, if you need it, have a siesta instead.
You’ll feel better for it come Monday morning.
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