Is it better to sleep for an hour or not at all?

We all need at least 7 hours of sleep to be at our best. But sometimes life gets in the way. You were up late cramming for an exam, preparing for an important work presentation, or simply too busy having fun with friends.

Whatever your reason, you now find yourself faced with the potential of an all-nighter. Is it better for you to sleep for an hour, or not at all?

The funny thing is: it’s a trick question. If you’re forced to choose between staying up all night or sleeping for an hour, the better option is to have just a 20 to 30 minute nap instead.

Surprised? We thought you might be. It can all be explained by your sleep cycle.

How your sleep cycle works

When you sleep, you cycle through different stages of sleep, from light sleep to deep sleep to REM and back again. Your sleep cycle refers to your progression through those different stages of sleep, and it changes throughout the night. In the first half of the night, you spend more time in light and deep sleep. As the night goes on, the REM portion of each sleep cycle increases. All in, we complete 4 to 5 sleep cycles a night.

Your first sleep cycle takes about 90 minutes. If you only sleep for an hour, you’ll cut that cycle short. Worse, you’ll probably wake up during deep sleep. Deep sleep, as you might guess from the name, is the restorative stage of sleep during which you’re deeply asleep. Your brain waves are at their slowest during deep sleep. If you’ve ever woken up extremely groggy, it’s likely your alarm went off while you were in deep sleep.

Which is better: sleeping for an hour or not at all?

Because of how sleep cycles work, it’s not a great idea to sleep for only 1 hour. If you can, sleep for 90 minutes instead. Then, you’re much more likely to wake up during light sleep, which is the easiest stage of sleep to wake up from.

Your other option is to take a power nap. If you nap for 20 to 30 minutes, you’ll wake up somewhat refreshed from your time in light sleep, but you won’t have slept long enough to enter deep sleep.

If you don’t trust that you’ll be able to wake up after a short nap, your best bet might be to not sleep at all.

In review, here are your best options for restful sleep when you’re short on time:

1. Sleep for 90 minutes.
2. Sleep for 20 to 30 minutes.
3. Don’t sleep at all.

And above all else, do not hit the snooze button when your alarm goes off!

Getting through the day after little to no sleep

Whether you enjoy a power nap or don’t sleep at all, you’re still going to feel exhausted the next day. To make things a bit more bearable, here’s our best advice for feeling energized after a night of little to no sleep.

• When your alarm goes off, get out of bed, turn on the lights, and open the curtains. Bright light, even if it’s artificial, will help wake you up.
• Real sunlight is even better. If you can, go outside and spend some time in the morning sunlight. For an extra energy boost, exercise. Even a brisk walk will activate your body and mind.
• Throughout the day, eat during your normal meal times to help your sleep schedule stay on track.
• Avoid overly sugary or fatty foods. You’ll be craving them (it’s an unfortunate effect of sleep deprivation), but you’ll be less equipped than ever to recover from the sugar crash.
• Indulge in caffeine early in the morning. Don’t overdo it, though, and cut yourself off in the early afternoon. You don’t want to end up so wired that you experience another sleepless night.
• If you’re absolutely exhausted, enjoy another power nap. You might even make it a coffee nap. Again, limit yourself to 30 minutes tops to avoid entering deep sleep.

Remember, your body needs at least 7 hours of sleep every night to function. This article is meant to help you if you find yourself in that rare occasion where you can’t get enough sleep. Avoid staying up all night in the long-term, or you’ll end up chronically sleep-deprived. That means you’ll have trouble focusing, you’ll be grumpy and moody, and you’ll make yourself more susceptible to illness.

Also, expect to feel less than great for the days following your all-nighter. The idea of catching up on sleep is a myth.