Humans weren't meant to go for along time without rest. That's why the Sabbath is a commandment, you should spend a day where you aren't working or worried about things. It's also why Jesus would continuously go off by Himself to pray to God, we were designed to need time at rest with God. This is totally against our society where everything is go, go, go, so it's hard to rest when everyone else is yelling at you to stop being lazy. Not that I'm saying you shouldn't work hard or anything like that, I'm saying you should work but you also need time set apart just to relax in God's presence. No one is their best self when running on little sleep and little rest, you're typically miserable and you make everyone else miserable. That's not what God wants for our lives so He told us we needed to rest and yet we still don't listen. You can't do life the way the world tries to tell you to do it, you need to take a break and just be with God. He will renew your energy and your peace.