Remember how we said you have five stages of sleep? Those stages together make up one cycle, which lasts around 90 minutes total.
You go through several sleep cycles over the course of a night. Getting out of bed can be hard if your alarm goes off in the middle of one, so try setting a wake-up time that’s a multiple of 90.
If you go to bed at 10 p.m., you may feel more refreshed at 5:30 than you would if you got a full 8 hours of sleep because you’re getting up at the end of a cycle.