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

https://www.fightful.com/boxing/fight-week-the-sleep-problem-nobody-talks-about/

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.