Nick Littlehales, a sleep coach who’s worked with many world-class athletes and is a fellow Penguin Life author (I can’t tell you how cool it is to be able to put myself in that category), has a new book, Sleep: The Myth of 8 Hours, the Power of Naps… and the New Plan to Recharge Your Body and Mind. The Guardian has an excerpt on the secret of power napping.

One of the most important secrets of power naps (or Controlled Recovery Periods, as he calls them), is that you don’t really need to sleep in order to get benefits. There are people who resist naps on the grounds that “they simply ‘can’t nap.’ But,” it turns, out, “it doesn’t matter:”

What’s important is that you use this period to close your eyes and disconnect from the world for a short while. Falling asleep is great, but so is catching that place on the verge of sleep, when you’re not quite awake but not quite asleep either. It’s tapping into that point of the day when you’re not really thinking about anything at all, when your mind is a blank.

This is what scientists call hypnagogia, and it’s a state that some creatives, most notably Salvador Dali, actively used to tap their creative subconscious. But, Littlehales reveals, even if you never have Surrealist visions of melting clocks, bring in that state does you good.