Everyone loves naps, as long as they've got the science of it down before they doze off. If you're one of those people who's not sold on a bit of midday sleep, you may have just been approaching it wrong — sleeping too long, for example, and at the wrong time of day.
How long you should nap is covered fairly often — 10 to 20 minutes seems the accepted norm for a productivity-boosting power-nap, 30 minutes may leave you quite groggy and disoriented without many discernible benefits, while one hour plus starts to help your brain to function better (though still may leave you a little groggy). From the Wall Street Journal:
For a quick boost of alertness, experts say a 10-to-20-minute power nap is adequate for getting back to work in a pinch.
For cognitive memory processing, however, a 60-minute nap may do more good, Dr. Mednick said. Including slow-wave sleep helps with remembering facts, places and faces. The downside: some grogginess upon waking.
Finally, the 90-minute nap will likely involve a full cycle of sleep, which aids creativity and emotional and procedural memory, such as learning how to ride a bike. Waking up after REM sleep usually means a minimal amount of sleep inertia, Dr. Mednick said.
More interestingly is the science of when to nap. Most of us start feeling a slump after lunch, and according to a Boston Globe infographic this can be the best time to nap. Early risers are recommended a nap between 1pm and 2pm, while late risers can leave it a bit later: 2pm to 3pm. The infographic also includes a heap of other interesting information on optimising your nap.
If you're after something even more specific, however, Dr Sara Mednick has an interactive nap wheel, allowing you to figure out the best time to nap based on the time you usually wake up.
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