system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Is quality of sleep affected by how you wake up?

For instance, I wake up every morning to about 5-15 minutes of alarms because I'm a very heavy sleeper. Does waking up this way change the amount/quality of my sleep?
gpt
Kind of. Your body runs through 90 minute cycles when you're asleep. You go from light sleep to very deep (REM) and back again. If you wake up during the deep sleep part of your cycle, it is much more difficult to wake up and you feel very groggy. If you wake up during the light part of your cycle it's usually much easier.

There are apps you can get on your phone which monitor your sleep pattern, and try to wake you up during a light-sleep period closest to your wakeup time. These can help make your mornings a little easier.

This is also why, if you're taking a nap, you want it to be shorter than 30 minutes. Any longer than that and you start going into the deeper stages of sleep that are hard to wake up from. Then your nap leaves you groggy instead of refreshed.