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The almost superhuman feats of Olympic athletes are the result of years of meticulous training and preparation. But one aspect is often overlooked – how they sleep. Few actually manage to get the kip they need.
On the day of his flight to the summer Olympic Games in Tokyo in 2021, Irish artistic gymnast Rhys McClenaghan woke up at 4.30am to fit in a training session, hoping to tire himself out. In a bid to defeat jet lag, he planned to sleep for just the first half of the 16-hour flight, hoping his body clock would slot into the new time zone – eight hours ahead of Dublin – when he landed.
"My coach says he should be able to wake me up in the middle of the night and I should be able to do a routine straight away," McClenaghan said in a video he posted on YouTube at the time. It seems being prepared to perform at any moment, even with an insufficient amount of sleep, is just part of the groundwork needed ahead of the historic sporting competition.
Most Olympic athletes undergo years, if not decades, of punishing exercise and conditioning regimes as they get ready to compete at the height of their sport.
Yet sleep is a crucial and often overlooked part of how someone performs in at the Games.
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It is well-known thatsleep is essentialfor the brain and the body. Not getting enough of it can contribute topoor mental and physical health. And while we all feel the consequences of a bad night's sleep, in the world of elite sport – where shaving fractions of a second off a time or making micrometres of adjustment can mean the difference between winning or losing – it can make a world of difference. At the 2008 Beijing Olympics, for example, a1% improvementwould have meant a gold medal for the competitor who came fourth place in the women's 400m swim, 400m track race and the women's road race. It would also have clinched the fourth-place sprinter in the men's 100m a silver medal.
Certainly,much of the scientific researchpoints at how poor sleep and sleep deprivation can have a harmful effect on athletic performance. Many elite athletes worksleep into their training schedulesas an essential part of their preparation for competitions. US Olympic gold medal-winning sprinterGabby Thomas, for example, has described how prioritising sleep has helped her to become one of the best runners in the world. The British Cycling team even went as far astaking their own pillows and mattresses to the Beijing Olympics in 2008so their athletes could sleep in the same position every night to help give them the "marginal gains" that saw the team win seven out of 10 gold medals available in track cycling.
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According to one study by researchers at Stanford University, extending sleep by spending at least 10 hours in bed per night improved sprint times, shooting accuracy and decreased fatigue among college basketball players. The researchers say sleep and rest was as important as training and diet.
Other studies have shown that elite athletes who have their sleep restricted to four hours per night for three nights suffer a decrease in joint coordination and aren't able to jump as high as they could with more than seven hours of sleep a night.
For ultramarathon runners, the time spent asleep the nights before a competition accounted for around a third of the variation in performance among ultra-endurance triathlon competitors.
"If you talk about a pyramid, it's [sleep] the base, or the foundation of a building," says Matthew Crawley, assistant strength and conditioning coach and sport scientist for the Dallas Stars, and adjunct professor at Canisius University, in Buffalo, New York. "It's fascinating – when the body is recovering during sleep, the human growth hormone is released, and emotions are regulated... These are all complex physiological processes in the body that are overlooked."
How to improve your own sleep routine
According to Matthew Crawley, a sports scientist at Canisius University, there are a few basic steps you can take to improve your sleep before exercising:
1) Get more sleep – ideally aim for eight or nine hours a night
2) Develop a consistent sleep schedule with regular bedtime and waking routines
3) Personalise your bedroom environment – keep it cool, calm and dark
4) Wind down in the best way for you – a cold or hot bath, reading, meditation or breathing exercises
5) Limit use of electronics one hour before bed – use a night mode where you can
6) Crawley also recommends something he calls the 3, 2, 1 rule: no physical exercise for three hours before bed, no meals for two hours before, and no electronics for one hour before
For world-class athletes, sleep allows for better concentration, a better mental state during competitions, as well as improving recovery and consequently reducing the risk of injury. However, Olympic athletes frequently get less than the recommended eight hours of sleep a night, especially the night before a competition. Studies reporting global sleep quality show that 50-78% of elite athletes experience sleep disturbance and 22-26% suffer with highly disturbed sleep. This may be due a variety of reasons – from early morning and late evening training sessions, unfamiliar sleeping environments, travelling between time zones and psychological stress due to performance pressures.
Negative effects of sleep deprivation on the performance of athletes include reaction time, accuracy, strength and endurance, as well as cognitive functions such as decision-making and judgement. But this can vary between sports and individuals – for example with something like archery, it affects fine motor skills, reaction time and decision making, as opposed to something like a 100m sprint, where they will feel the effects on their speed, power and endurance.
There is currently limited research into how specific sports affect sleep, though one study showed that individual athletes went to bed earlier, woke earlier and obtained less sleep than team athletes. This could be influenced by training demands – for example, sports like swimming and the triathlon may require multiple training sessions a day, which in turn could disrupt the quality of sleep.
Morning lark vs night owl
If you asked me to wake up at 6am to go to the gym, I would politely laugh in your face. The only thing I like to lift in the morning is the kettle full of boiling water for my tea. Whereas I struggle to exercise first thing in the morning, needing to let my body fully wake up, some people feel more sluggish in the evening. And there is some science behind this, as being a night owl or morning lark affects sports performance. (Find out more about the best time of day to exercise.)
Our bodies' internal clock cycles approximately every 24 hours. This cycle helps to align our sleeping cues with the environment, such as the hours of darkness, when we eat, or when we are physically active. This cycle is referred to as our circadian rhythm.
Researchers at the University of Birmingham, in the UK, found that an athlete's performance may also be different depending on their circadian rhythm, after 20 female field hockey players completed a multi-stage fitness test (also known as a BLEEP test) at six times of day, between 7am and 10pm. The larks peaked at 12pm, intermediates peaked just before 4pm and owls peaked just before 8pm, and there was a 26% difference between their best and worst times. Ultimately the results indicate how determining the circadian pattern of an athlete will help them and their team to understand when they perform best.
Team GB invested in sleep pods for the Paris 2024 Games to help optimise the quantity and quality of sleep for athletes
Crawley also mentions the process known as the homeostatic sleep drive that works concurrently with the circadian rhythm, increasing throughout the day to leave us feeling sleepy at nighttime. "Without sleep, it can be challenging for the body to regulate metabolism, immunity, neurological function, cognitive function, emotional and physical health," he says.
Though it's unlikely official competitions will ever change because an individual athlete may perform better at a certain time of day, Crawley believes that personalising training and sleeping routines according to an athlete's circadian rhythm could "change the future of training".
Is technology changing the way we analyse sleep?
While sleep diaries and questionnaires can also be effective to keep track of how you feel you slept, wearable fitness devices are increasing in popularity as they give concrete data about sleep quantity and quality. They track stages of sleep – REM (rapid eye movement) and non-REM (which is further broken down into light, deeper and the deepest stage of sleep) – as well as sleep duration and latency (how long it takes you to fall asleep). Analysing the metrics allows sleep experts to get insight into sleep patterns and identify the areas where athletes can improve their sleep hygiene.
However, this might not work for all athletes, some of whom might feel more stressed by the figures each morning, says Crawley. "Some might not look at it the night before or the day of a competition as it might affect their psychological preparation, for example if they only managed to get six hours of sleep the night before, but they know they probably need at least seven or eight to feel great to perform," Crawley says.
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How can athletes achieve a healthy sleep routine?
New research is showing that sleep hygiene routines are an effective way for athletes to regulate their sleep, and to ensure that they make sleep a top priority. However, it takes commitment – for example, waking up at the same time each day, establishing a bed-time routine, limiting caffeine and avoiding blue light from electronic devices. McClenaghan, for example, wears red-lens glasses to block out blue light while travelling. (Intriguingly, while blue light exposure before bed can affect sleep quality, at other times it can improve reaction time and alertness, which could be beneficial in some sports.)
"Understanding their upcoming schedule is important – what does the training week look like? When is the competition?" says Crawley. "Could they go to bed a little sooner, or focus on getting sunlight in the morning before travelling?" Sunlight in the morning helps to regulate or circadian rhythm, by boosting our serotonin levels and in turn suppressing melatonin (a naturally occurring hormone which rises at night to help control how and when you sleep).
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A new concept of "banking sleep" (sleeping for longer the night before a night of deprived or disrupted sleep) has also been suggested to improve athletic performance. Napping is also been shown to bring positive effects to sports performance – a quick 30 or 90 minutes of shuteye has been shown to boost alertness and reduce sports-related fatigue.
Though it may not be the most helpful for those who struggle to fall asleep, napping can be used to supplement a night of bad sleep, or to combat "daytime sleepiness". In fact, Team GB invested in sleep pods for the Paris 2024 Games to help optimise the quantity and quality of sleep for athletes in a high-pressure and unfamiliar environment.
I guess my days of scrolling on my phone before bedtime are over, because if moaning about how badly I slept the night before was an Olympic sport, I'd definitely have a gold medal.
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