How can complete sleep 8hrs?im only sleep 5-6hrs?

Answer:
If you feel well-rested with 5-6 hrs that might just be your circadian rhythm (google for some defintions). An average of 8 hrs of sleep is probably from clinical studies and people can vary from the mean of 8 hrs so if 5-6 works for you that's fine. If it's not, I think it is easiest to put yourself on a schedule. If you go to bed at 8pm one night, then 9pm, 1am, etc. other nights your body can't really time when you should go to sleep and when to wake up. Try and choose a consistent time to go to bed and make sure it around a time when you are tired on average.

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