There's a debate happening on Twitter over how long a nap should last. First of all, let's get one thing straight: naps should last as long as they need to last. Some days that means 20 minutes, some days that means tow hours. And sometimes we need naps to be longer! Like when you put the baby down. If that kid doesn't nap for AT LEAST two hours, consider your day ruined. But while people may not be able to agree on how long a nap should be, science has weighed in and their opinion. And science is pretty much always right!

The nap debate on Twitter is all over the place. Some people say around 20 minutes, which seems WAY too short, to be honest.

Some people say anywhere between 2 - 6 hours, which ... at that point maybe you should just go to bed? Waking up after a six hour nap is rough.

The nap debate seems to have gotten pretty intense, resulting in one Twitter user starting a poll to get some opinions. With nearly 71,000 votes, 49% of respondents say 1 - 2 hours is ideal nap length. Agree!

Turns out, science agrees with that, too. According to Science of People, the ideal nap length is 90 minutes. Sleeping for 90 minutes allows you to reach your full sleep cycle and hit rapid eye movement (REM) sleep. Also, 90-minute naps can help you avoid that awful groggy feeling you experience after waking up from a nap. It's called sleep inertia, and can be the result of too-short naps. If you nap for an hour and a half, you wake up feeling more rested and refreshed.

In addition to there being an ideal nap length, did you know there's also an ideal nap time? The same researchers at Science of People say the best time to nap is between 1 p.m. and 4 p.m. Any earlier and you may not be tired enough to fall asleep and hit that REM sleep. Any later and you run the risk of doing some serious damage to your sleep schedule that night.

Obviously, we all need to take more naps. Science says so! Let's figure out a way to make 1 - 4 p.m. official nap time, and hit the hay for 90 minutes. We can all agree that naps are awesome, and if science says to sleep that long, who are we to argue?

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