Rule #7: Sleep well, think well.

When we’re asleep, the brain is not resting at all. It is almost unbelievably active! It’s possible that the reason we need to sleep is so that we can learn.
Sleep must be important because we spend 1/3 of our lives doing it! Loss of sleep hurts attention, executive function, working memory, mood, quantitative skills, logical reasoning, and even motor dexterity.
We still don’t know how much we need! It changes with age, gender, pregnancy, puberty, and so much more.
Napping is normal. Ever feel tired in the afternoon? That’s because your brain really wants to take a nap. There’s a battle raging in your head between two armies. Each army is made of legions of brain cells and biochemicals –- one desperately trying to keep you awake, the other desperately trying to force you to sleep. Around 3 p.m., 12 hours after the midpoint of your sleep, all your brain wants to do is nap.
Taking a nap might make you more productive. In one study, a 26-minute nap improved NASA pilots’ performance by 34 percent.
Don’t schedule important meetings at 3 p.m. It just doesn’t make sense.