Sleep and Sport

Sleep is a complex physiological process that scientists are only just beginning to understand.  We do know that when you are asleep, there is a clear alteration in the activity of the brain.  There are also changes in the levels of some hormones, for example, growth hormone is released during the deeper stages of sleep.  Sleep is described as a highly restorative process.   

Studies where sleep is deprived of animals and humans show that there are plenty of negative effects caused by the sleep loss. For example, immune function is impaired by sleep loss, increasing the likelihood of infection.  A famous study in 1989, where sleep was totally deprived from rats, reported that the rats all died within one month.  Although the picture is a little different in humans, this shows the importance of getting plenty of good sleep.

We also know that exercise has a profound impact upon sleep.  Up to a point, the more you ask your body to do in the day, the more sleep is required to recover.  This is why endurance athletes in particular generally need more sleep.  However, excessive exercise can actually disrupt sleep, so it is important to strike a balance.      

Successful training, particularly for endurance sport, is a balance between physical work and subsequent recovery.  It has been said that winning athletes are not those that train the hardest, but those who recover the most effectively.  Training is all about recovery.  Each training session causes damage to the body which must be repaired.  Over time if recovery is inadequate, the body eventually breaks down.  

Recent research has shown that Rapid Eye Movement (REM) sleep, which is the deepest stage of sleep but where the brain is most active, is essential for improving memory and learning, so this could be crucial for athletes learning complex tasks.  ‘Power naps’ may also be effective in restoring mental alertness, although these do not offer the same restorative benefits as sleeping at night.   

If you are getting good sleep then there is no need to try to improve it, however, some simple tips can often improve things where sleep is poor.  For example, not training too late in the day, ensuring the bedroom is very dark and very quiet, and avoiding excessive caffeine intake and all help to promote good sleep.  This is called good sleep hygiene.