Comments by "Grey Matters" (@o0GrayMatters0o) on "#Mind Warehouse" channel.

Everybody is different but a good rule of thumb is 3 REM cycles a night for recovery and regeneration is best. They're about 2 hours each and take approximately 30 minutes to get in and out of. That's 7 hours and 30 minutes for people that exert energy throughout the day. If you are mostly sedentary, it will be harder to fall and stay asleep, just as if you are physically active more than most, you will need more sleep. Stress and adrenaline levels have a lot to do with it too. With that said, I've heard of some workaholics and students who prefer 3-4 hours of sleep so that they can maximize their productivity in their waking hours.
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