DJs and producers know the 4 AM body clock all too well — mixing beats at 4:12...

https://wiki-room.win/index.php/Why_Does_My_Body_Feel_Like_It%E2%80%99s_in_Four_Time_Zones_at_Once%3F

DJs and producers know the 4 AM body clock all too well — mixing beats at 4:12 AM, facing a 9 AM flight, then sliding on sunglasses for the ride home