First let’s explore what happens if you have a crappy night’s sleep before your big race, game, or competition.
In 2014 a study was conducted with marathon runners. The runners were asked the morning of the race how they slept and had to estimate how they would do. 70% of the runners reported worse sleep, however the was no difference between their estimated performance and their predicted performance. So - one poor night sleep didn’t necessarily effect their running performance but it did affect their mood. The runners reported worse mood, more tension and more fatigue. (Lastella et al., 2014) Additionally - studies show poor sleep on a single night affects your submaximal output – but not your maximal efforts. Your mood deteriorates before your strength, and perceived exertion increases while endurance decreases slightly. In short - if you sleep bad one night - you won’t be in as good of a mood, things might feel a bit more difficult - your endurance will be down a bit, but overall you can still perform at a high level. https://www.youtube.com/watch?v=wWDhHHnYbt4But what happens if you get continuing bad sleep?
Well - in a study using younger athletes a lack of sleep resulted in increased injury. In fact - Athletes who slept on average <8 hours per night were 1.7 times more likely to have had an injury, compared with athletes who slept for ≥8 hours.
Not only does continuous poor sleep or a lack of sleep put you at higher risk of injury… but your performance suffers.
In a study they made subject sleep for 4 or 6 hours per night for 14 days and here’s what they found.