Sleep comes before everything else. Clearly sleep is important, as we spend almost half our lives doing it. For an athlete, it is the greatest recovery tool we have in our toolbox. What does sleep do for us? Recovery, rebuilding cells (that means brain cells, muscle cells, repairing all the damage done throughout our daily life), strengthening our memories, cleans out waste products from the brain, helps regulate mood and appetite. It helps strengthen the cardiovascular system, immune system, and balances metabolism. Sleep help manages production of cortisol, growth hormones, and hormones that manage appetite.
While you're sleeping, your body releases growth hormones to repair all the damage done while living your life during the day. If you want to repair your muscles efficiently, sleeping is the best way to do it. Another hormone that actually decreases when you sleep is cortisol! Cortisol is often released during stressful situations in order to provide a jolt to get through the difficulty. It also peaks right after you wake up in order to get your alert and ready for the day. While this sounds great, cortisol is not necessary in excessive doses and therefore sleep is important to decrease those levels and allow your body to rest and recover.
When you sleep, your brain basically reviews the days input and processes information to create long term memories. Lack of sleep results in poor concentration, poor focus, increased irritability, poor mood stability, lower energy levels, and puts you more at risk of injury. Without enough rest, your blood pressure can increase and your body doesn't get the chance to shut off it's fight or flight mode. This level of alertness is not good for your ability to manage stress and thus can increase not only cardiovascular stress, but anxiety and depression. When you're sleeping, you're giving your heart a rest. We often think about giving our muscles a rest that we exercised, but sleep also allows your heart rate to come back down and improves your overall cardiovascular health and ultimately aerobic strength.
The Sleep Foundation notes that after a period without enough sleep, people can go into a state of REM rebound, in which their body is spending too much time in REM and not getting adequate deep sleep. Your brain is basically working in overdrive when it should be resting, and this can increase depression and anxiety.
The most impressive component of sleep, in my opinion, is the release of cytokines. These are tiny proteins released by your immune system in order to fight inflammation. Whether that inflammation comes from sickness like a cold, or physical injury, these little proteins help fight that inflammation and boosts your immune system!
On your rest days when you don't need to get up at the ass crack of dawn for a workout, it might be worth it to sleep in! On these days, nothing helps us recover and rejuvenate our minds and bodies more than sleep. Sitting around binging Netflix is great and all, but spending some of that time actually sleeping will do wonders.
If this information didn't convince you to sleep longer, how about some of these stats:
The following improvements happened when athletes slept 9-10+ hours per night (I know that is difficult for those of us who are not professional athletes, but the jist is that getting some extra sleep is good.):
-Basketball players were faster in their full and half court sprints and shooting accuracy improved 9%. That's huge.
-Swimmers had faster reaction times, improved agility, faster swim sprints, and faster kick strokes.
-Tennis players' accuracy increased by 6%
Without adequate sleep:
-Athletes accuracy, speed, agility, reaction time, and time to exhaustion decreased. We don't want any of this.
-Increased RISK OF INJURY. This is enormous.
-People make poor decisions.
While studies suggest 9+ hours of sleep for elite athletes, for recreational athletes, we require 7-9 hours of sleep per night. We should be treating sleep equally as important, if not more important as our training sessions. Lack of sleep vs adequate sleep has more of an impact on your athletic abilities than getting in an extra rep or an extra mile.