The 10-20 Minute Sweet Spot

Nap length matters enormously. The ideal power nap lasts 10 to 20 minutes, which keeps you in lighter sleep (stages 1 and 2). You get the alertness and thinking benefits without the grogginess that comes from deep sleep.

• 5 minutes: Barely enough to reach stage 1
• 10-20 minutes: The sweet spot, a real alertness boost with no grogginess
• 30 minutes: Risky, you may hit deep sleep and wake up feeling worse
• 90 minutes: A full sleep cycle, great for recovery but impractical at work

Set an alarm. Once you fall asleep during the afternoon dip, your body will happily take two hours if you let it.