Carrying out athletics at any level requires significant focus and training. When we think of elite athletes’ training, we probably visualise some physically gruelling Rocky-style training montage involving thousands of press-ups, chin-ups and ridiculously fast skipping. There might even be a couple of scenes involving eating raw eggs or downing a protein shake. Probably no one imagines an elite athlete sleeping. Yet, sleep sits alongside exercise and nutrition in what is known as ‘The Three Pillars of Health’.
Much is written on the importance of different exercise regimes and specific fitness diets, but there is generally very little advice on how and why an athlete should get good sleep. Ignoring one of these vital functions will cause the remaining two to suffer. Understanding how sleep impacts athleticism gives an interesting perspective on modern international sports.
Elite athletes are frequently known to get less than their required sleep. The reasons for this vary, but a common cause is the strict training timetables they have to keep that often involve early starts and late finishes and cut into the periods when normal healthy sleep would occur. Even if athletes have adequate opportunities for sleep, they may find that pre-match anxiety will keep them awake. Travelling across time zone can bring an extra element that will disrupt sleep. In addition, athletes are often unaware of the importance of sleep, especially when so much emphasis is placed on the other two pillars of health.
Sleep is vital for sports in two ways. One is a component of fitness and training, and the other is by giving you the edge in your performance on the day.
Most of your body’s growth and repair occurs in a specific sleep stage called ‘deep NREM’. This is facilitated by having most of your growth hormone released from your pituitary gland during this stage. Sleep also replenishes muscle glycogen, the energy stores needed for endurance. Sleep is also vital in learning new skills due to its effect on memory. Many studies have shown the benefits of sleep in learning lists of information, known as declarative memory. But sleep is also needed when consolidating muscle memory.
The ‘on the day’ effect of sleep cannot be underestimated. Sleep profoundly impacts mood and will help you get ‘in the zone’ for a big match, race or event. Multiple studies have shown how strength, speed, accuracy and reaction time are all improved with good sleep.
One study in 1994 looked at how the weightlifting performance of 18-24-year-olds changes following sleep deprivation. The weight lifting performance was measured over four days of normal sleep, then repeated following three nights of just three hours of sleep. Muscle strength was substantially lower when sleep deprived.
Another study in 2003 compared the aerobic performance of cyclists when having normal sleep, then when sleep deprived for 24 hours and again after 36 hours of no sleep. The cycling performance was maintained up to 24 hours, but after 36 hours of no sleep, their performance level dropped across the board.
There have been several other interesting progressions of these kinds of studies, including one assessing female swimmers who received 2.5 hours less sleep each night over four nights. The study found that the physical aspects of performance, such as muscle strength and lung function were maintained. However, the psychomotor aspects of performance all deteriorated. Depression and tension increased, and vigour – the self-reported feeling of energy and enthusiasm, dropped. A number of other studies have shown those crucial psychological aspects of performance, such as reaction time and decision-making, often get affected first.
Increasing the amount of sleep an athlete gets has extremely beneficial effects on both the psychomotor and cognitive aspects of performance. A study looking at male basketball players got them to increase their sleep by around two hours per night for six weeks. Shooting accuracy went up by almost 10%. Vigour and mood all improved, as well as sprinting time.
Another study confirmed the improved reaction times from swimmers diving from the starting boards and increased kick stroke efficiency following two hours of extra sleep a night.
As well as assessing the effect of better overnight sleep, several studies have reported the impact of a 30-minute daytime nap. One study cut volunteers to four hours of sleep a night and confirmed the expected drop in vigilance tasks. When the volunteers had a 30-minute power nap at midday, their vigilance scores returned to normal. This provides a possible solution for athletes who struggle to get a full night’s sleep. Many athletes are famous proponents of power napping, including sprinter Usain Bolt and Basketball player LeBron James.
As humans are so dependent on light for functioning, we have evolved to be most active during daylight hours and rest at night. This fluctuating activity level is governed by our internal body clock, or circadian rhythm. A strong circadian rhythm promotes daytime alertness and a natural urge to sleep in the evening. Moving an individual with a strong and healthy functioning circadian rhythm from one time zone to another is highly disruptive but, unfortunately, familiar in top-level sports. This jet lag causes feelings of sleepiness and wakefulness to occur at the wrong time of day.
Besides sleep and wake, the activity of many other biological functions wax and wanes with this rhythm. Alertness and muscle function are essential areas regarding sports. Many studies have concluded that maximum muscle function occurs between 4pm and 8pm.
The impact this has on sports was nicely summed up in a study of American football teams across 40 years. America is enormous, and the mainland crosses four different time zones. A study looked at the impact of time zone shifting on the performance of West Coast NFL teams when they play away against East Coast teams and vice-versa. The study balanced other factors, such as the benefit of playing in your home stadium.
While no significant difference was noticed when a West Coast team played an evening game on the East Coast, when it was the other way around, East Coast teams played significantly worse in evening games on the West Coast. This is because the East Coast is three hours ahead, so a game finishing at 10pm in the West would be the body clock equivalent of finishing at 1am for an East Coast player. The only touchdown you want to do at that time is head to pillow.
Athletes improve this sleep in many ways the general population does. The first is to make sleep a priority and ensure adequate opportunity for sleep is made. Sleep hygiene advice can improve sleep quality and quantity.
Ensuring any formal sleep disorders are diagnosed and treated. Athletes are often considered to be in peak fitness, but this doesn’t mean they cannot get sleep disorders. Insomnia and obstructive sleep apnea can be especially prevalent in certain athletic groups, and they can both be very effectively treated.
Sleep banking is a technique used by some athletes. This involves getting more than the required night of sleep in the run-up to an event when you know you’ll get less sleep – either due to jet lag or pre-match anxiety. This obviously depends on the athlete’s ability to command more sleep when they want, which isn’t a skill everybody has!
Tactical napping is another key road to success. Many premiership football clubs now have facilities purpose-built for a power nap. This is something that several office-based industries are starting to adopt as well.
While we might not all be elite athletes, we all have things we strive towards and days we need to be at our best. In the same way that sportspeople often inspire us to achieve great things, their successful approach to health and fitness, which includes sleep, should be no different. The same lessons that can lead Usain Bolt to nap and then shortly after winning his first Olympic gold medal can help us achieve in our own lives.
If you consider the correlation between sleep and athletic performance prevalent to yourself, get in touch at www.thebettersleepclinic.co.uk.