Whenever I see someone going to bed late and getting up early but still feeling energetic, I feel that it may not be necessary to sleep a full 8 hours.
But when I don’t get enough sleep, I find that my ability to focus and understand has declined, and I can’t muster the energy to do anything.
Why are we so different? Why do some people have so much energy even when they don’t get enough sleep?
How do we figure out our sleep needs?