Sleep and How it Impacts Performance

By: Taylor Heppner

How well do you sleep? How well do you perform? Do you have an injury? The relationship between sleep performance and athletic success is significant and should not be ignored by motivated athletes.  

Stages of Sleep

We have all heard that we should be getting 6-8 hours of sleep per night, but do you know what happens during that time? While you are asleep, your body cycles through two main stages. They are identified by your watch as light sleep and deep sleep. Both stages are precious to your recovery, next-day energy, and overall health.

Light Sleep

As soon as you fall asleep, you hit light stage sleep. In this stage, you can be woken up more easily or disrupted. Your body is starting to relax by slowing heart rate and breath rate.

Deep Sleep

When in deep sleep, it should be tough to be woken up, that means that you are fully relaxed, mind and body. Your breathing and heart rate have slowed down and are steady in this stage. Increased blood flow to your muscles in deep sleep increases oxygen and nutrients necessary for muscle regeneration being delivered to the tissues. The pituitary gland releases growth hormone in deep sleep as well. Growth hormone is essential for muscle recovery and growth. Additionally, the release of prolactin hormone in deep sleep fights the onset of inflammation. When you hit those deep sleep stages, your body is in full recovery mode. If you want to perform at a high level in the subsequent days, you need to maximize deep sleep hours! 

Injuries and Sleep

Suppose we are consistently getting too little sleep. In that case, there is a dramatic decrease in physical/sport and lung performance and decreased time to fatigue (by about 30%). There is also increased risk of injury (by about 60%), and an increase in lactic acid buildup. The less sleep we get consistently, the more likely we are to injure ourselves or others. Car crashes are an example. Sleep-deprived drivers are roughly 11.5x more likely to cause an accident.

In sports injuries specifically, if you are consistently getting less than six hours of sleep per night, you have over a 70% chance of injury. That percentage dramatically decreases with even just one more hour of sleep. If you managed to get 8 – 9 hours of sleep per night, your chance of injury decreases to 15-35%.

However, if we can better our sleep and build more consistent, healthy sleep habits, we can see improvement in all of these areas. After a bout of high-quality sleep, consistently, you are 20-30 times more effective at movements you learned the day prior. Essentially your brain rehearses while you are sleeping.

Sleep and Wake Drive

Circadian rhythm and adenosine are independent; therefore, your circadian rhythm ignores adenosine buildup. Circadian rhythm is more or less your drive to be awake, and this cycle would happen even without sunlight. Adenosine is your sleep drive, and it builds up throughout the day, and sleeping decreases or clears, that build up.

The relationship between circadian rhythm and adenosine is why after a period of extreme sleepiness, many people feel they get a second burst. That burst of energy is simply the restarting of your circadian rhythm. Still, your sleep drive (adenosine) will keep building up. If somebody consistently fights the urge to sleep, they risk sleep deprivation. In a constant sleep-deprived state, humans are 10x more likely to experience depression and 3x more likely to be obese. All the good stuff that is supposed to happen naturally during deep stage sleep is skipped in sleep deprived states. So now, not only are you tired and moody the next day, but your muscles have not recovered, and your performance will take a hit.

Optimal Performance

After just 20 hours of being awake, human performance is comparable to legal intoxication. Many people go through their daily lives in a state of sleep deprivation. Sports performance can be dramatically improved if we are not in this constant state of haze by simply allowing ourselves to get adequate sleep. Did you know that most Olympic records are set at the peak of average circadian rhythms? That peak happens in the early afternoon – in case you are planning for a competition or choosing your next race! But if you happen to be in a state of sleep deprivation, you cannot just snap out of it. It takes up to two weeks to return to baseline performance without outside agents (any variety of sleep medications) after sleep deprivation. 

How to Improve?

Sleep is essential, but what can you do about it if you do not have great sleeping habits? You’ve probably heard most of these tips and tricks before, but it doesn’t hurt to try to re-implement them and create a routine around bedtime to help your body unwind. The ideal temperature range for optimized sleeping is 65-72°F (18-22°C). All screens and aggressive sounds should be off, even put a small piece of tape over tiny lights like on a fan or smoke detector so that your space is completely dark. Cut out that “relaxing” or a habitual nightcap, and try cutting out your afternoon caffeine intake.

Suppose you tend to wake up throughout the night or are very hungry in the mornings; try adding a high-protein snack before bed. A snack provides your body with a source of protein to start rebuilding with while you are sleeping. That process will use some energy and help you feel a little more sleepy. And if all of this does not help you feel ready to go to sleep, do not just lay in bed awake and frustrated; it’s a sign you have too much energy. Get up and do some small, manageable tasks around the house and then when you are feeling tired, get back in bed.


Sleep performance is one of the most important components to athletic and daily success. By monitoring your sleep patterns on your watch, you can begin to build awareness into how much light and deep sleep you’re getting. Perhaps you will mix in a few tips noted above as you increase your sleep performance. As your sleep improves, you’ll find you have more energy and can begin to explore perfection!