" So how much rest is “adequate”?

Science says: 42 percent.

That’s the percentage of time your body and brain need you to spend resting. It’s about ten hours out of every twenty-four. It doesn’t have to be every day; it can average out over a week or a month or more. But yeah. That much.

“That’s ridiculous! I don’t have that kind of time!” you might protest—and we remind you that we predicted you might feel that way, back at the start of the chapter.

We’re not saying you should take 42 percent of your time to rest; we’re saying if you don’t take the 42 percent, the 42 percent will take you. It will grab you by the face, shove you to the ground, put its foot on your chest, and declare itself the victor. "

― Emily Nagoski , Burnout: The Secret to Unlocking the Stress Cycle