Simply being awake ages you and damages the brain and body. Sleep effectively reverses some of that:
The number one thing you can do for health and fitness is take a look at your rest, recovery and sleep patterns, and how to optimize them.
Oftentimes, in a first appointment, people look at me puzzled when I’m more interested in this (I.e. - stress management) than food or training. But it’s no small thing. In a way, it’s everything.