Individuals should determine if napping interferes with their nighttime sleep and adjust nap duration accordingly, with naps over 90 minutes potentially problematic.

“I nap every afternoon. 10 to 20 minutes. As long as it doesn’t interfere with your nighttime sleep you’re good.”

“60-90 for folks that have a problem with a really big afternoon dip in energy. I suggest people try it.”

“1) Keep them to 90min or less”

“And there are essentially two varieties of people: people for whom napping interferes with falling asleep later that night and staying asleep and people for whom the nap does not interfere. You have to decide who you are. And if you're somebody who can nap and not have any trouble falling asleep and staying asleep later that night, well, by all means, nap. Just make it 90 minutes or less. Again, these 90-minute cycles are really a vital constraint that we should all obey. If it's 91 minutes, don't worry. You won't dissolve into a puddle of tears. But if you're starting to sleep for an hour or more in the afternoon, that can be problematic.”

“Naps should be 90 minutes or less, and 20-minute naps are fine, but not longer than 90 minutes.”

“do not nap after about 300 p.m.”