You've heard it a thousand time from your trainer already: sleep is important, and you need between 6 to 8 hours a night minimum. That's all fine and dandy if it weren't for life getting hectic, deadlines to be met and parties to be attended.
Why is sleep so important? how much do we really need? can we sleep less on some nights and then more on others? Let's figure all this out.
What happens when you sleep
There are 3 very important systems that are affected by sleep: your nervous system, your hormones and your brain waste removal.
Let's talk about the waste removal part first, because I think it's the most important one yet no one really talk about it. Your brain has only two modes: ON and OFF. When it is ON, it does all the information processing that we know it to do. This happens mainly when we are awake. Beta amyloid is a molecule that builds up around your brain cells during this activity. The build up deteriorates communication between brain cells over time. When the brain is OFF, it flushes the beta amyloid out. The brain cannot be on and off at the same time, hence the importance of sleep.
Next up, the nervous system, is also related to the brain. Sleep deprivation affects the quality of nervous cells communication. That's why it affects cognitive function, mood and memory. When you sleep, your nervous cells get a chance to relax and recuperate.
Hormones! Long story short, sleep plays an important role in blood sugar regulation by lower cortisol levels and increases growth hormones. But it also helps regulate your hunger hormones ghrelin (I'm hungry hormone) and leptin (I'm not hungry hormone).
The waste removal system plays a major role in the long term. You won't feel the beta amyloid build up for decades. On the other hand, you will feel the negative effects of the nervous and hormone system in a matter of hours and you will be able to physical see these effects in a matter of weeks if not days.
How many hours should you sleep
You should know by now that I don't believe in general recommendations by now since we are so different. some people will need more sleep than others, that's a fact. It seems like nowadays, the ability to sleep little is valued. Yes there are some individuals that require less sleep than others, that doesn't mean we can all survive on 4-5 hours of sleep a day. I seem to be fine with 7 hours per night. My morning clients can testify that any less than that I'm not fully operational.
Napping for less than 20 minutes has been shown to increase cognitive function. The same is true for longer naps but they do screw up your sleep cycles and you feel more drowsy after them. It has been observed that naps are more effective for people that do them regularly. So if you're going to nap, make it a habit, your body will benefit more from it.
Tips to sleep better
Let's keep it super simple here: exercise, diet and staying away from screens are your best friends for a good sleep.
Exercise increase the quality of sleep and diet just entails not eating 2 hours before your bedtime so that you're not digesting food while trying to fall asleep.
Screens are a constant problem for modern sleep since they are everywhere. When your eyes receives the light from your screen, it doesn't differentiate it from sun light. So your the information relayed to your brain says that it's still time to be up because the sun is still up.
Our bodies are very complex machines, with many systems at play to make it function properly. The complexity lies in the fact that all system are intertwined and work together as a whole. These systems need time to recover from your daily activity, even if you didn't do much. You don't feel your cells working, yet I assure you that they are constantly doing something when you are up.
Humans have been around for millions of years, if sleep weren't necessary for survival, we would of evolved out of it by now. So just because modern society values less sleep, doesn't mean it's a good idea.
Sleep plays a very important role for your body and should be treated with the same attention you give to diet and exercise in your endeavour to take care of your body.