Fight week sleep is a killer. Fighters often hit the sack around 4 or 5 am but...

https://future-wiki.win/index.php/What_Is_Sleep_Banking_and_Does_It_Help_Before_Fight_Week%3F

Fight week sleep is a killer. Fighters often hit the sack around 4 or 5 am but have to be up between 2 and 4 for weigh-ins Friday morning. Add six hours in a noisy locker room before doors open at 6 pm, and it’s no wonder sleep doesn't stand a chance.