It's ridiculous how many times a week I have to remind myself of this. Even if I'm not physically moving around, I'm almost constantly working on something; stressing over it, sweating over it, whatever. And honestly, if you force yourself to keep going and going even after you've reached overkill level, you will burn out. You need to take "you" time and you need to just chill out a bit every now and again.
Oh, and this beautiful photo is courtesy of my lazy, bum-of-a-cat, Zelda.