How could I change my biological hour ?

♥ ♥ did you mean your clock? ♥ ♥

If you are refering to being either a morning person versus a night person or if you are flying somewhere from a different time zone then you need to stay awake long enough that you are so tired that you will go to sleep at the time you have chosen. For example, if you land somewhere and it is the middle of the day, but your body feels like it is the middle of the night, then shower, walk, etc. until the nightime of the place you are in arrives and then you will crash. The time works if you want to change your hours where you live too. Just keep yourself awake. It may take a few days to adjust to, but you will.

Use your will power and tell yourself "I need to change my internal alarm clock". Focus on the time you wish to fall asleep and wake up. Try it!! It really works. Exercising early in the day will also help. Good luck to you ;)

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