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Guide

Why you wake up groggy, and how to stop it

4 min read · Last updated · By Infinity Tools

You know the feeling. The alarm goes off, you sit up, and for the next twenty minutes your head feels like it's full of wet sand. You got seven hours. So why do you feel worse than when you went to bed?

There's a name for it: sleep inertia. It's the slow, foggy stretch right after you wake up, and nearly everyone gets it to some degree. How bad it is depends a lot on what your brain was doing when the alarm went off.

Your night runs in cycles

Sleep isn't one long, even block. You move through stages: light sleep first, then deep sleep, then REM, which is where most of the vivid dreaming happens. Then the whole thing starts over. One loop takes roughly 90 minutes, give or take (National Sleep Foundation), and most people go around four to six times a night.

Deep sleep is the hard one to come out of. Your brain waves are slow, your body is busy with repair work, and if an alarm drags you out of it, you'll feel it for a while. Light sleep, near the end of a cycle, is much easier to wake from, and you may feel more refreshed if you wake up then (National Sleep Foundation).

Time the alarm, not just the hours

That's the whole idea behind the sleep calculator. Instead of picking a bedtime at random, you count back from your alarm in 90-minute steps and add a little time to fall asleep. Need to be up at 6:30? Getting into bed around 9:15 or 10:45 lines you up with the end of a cycle.

It isn't exact. Cycles vary from person to person, and even from one part of the night to the next, so treat the times as a good place to start. If you find yourself waking a few minutes before the alarm, you're probably close.

Small things that help more than you'd think

When it's more than grogginess

If you're worn out every morning no matter what you change, or someone tells you that you snore loudly or seem to stop breathing at night, it's worth talking to a doctor (National Sleep Foundation). Sometimes the fix isn't the alarm clock.

General information only, not medical advice. If sleep problems are affecting your day-to-day life, talk to a doctor.