: Why is it recommended to have 8 hours of sleep when sleep cycles happen every 90 minutes, wouldn’t waking up at 8 hours be in the middle of your cycle?

Question

I’ve learnt a little about sleep cycles and remember that every 90 minutes is when we move through the 5 stages of sleep, but I’ve also heard it’s recommended to have 8 hours of sleep. Wouldn’t that make you feel drowsy if you’re interrupting the sleep cycle when you wake up after 8 hours?

In: Other

Answer 1

For about 10 years now I’ve heard it as 9 hours instead – 6 sleep cycles.

People said 8 hours before they knew much about sleep cycles, I think. And now, many people remember the old stand-by and haven’t learned about the sleep cycles, so the old saying doesn’t die.