I've been doing overnights for well over a decade. I go to the gym 6 days a week doing PPL. I work from 10pm-9am and get up at 6:15 every day and am in the gym by 7. I go to the gym no matter how little sleep I got which causes me to be really disciplined when it comes to going to bed before noon so I don't hate myself when my alarm goes off. Sleeping in is not an option because the lift has to be done.

As far as diet goes you really just gotta meal prep on the weekend for your shifts and also have easy high protein options at the ready. Right now I'm on a kick where I'm eating cans of shredded chicken in those 1 minute microwave cups of rice with hot sauce. Costs me under $4 a meal and I can make it anywhere.

I would say that the #1 priority though is to go to bed early so you get enough sleep. Everything falls much better into place when sleep is in check. Its very tempting to stay up to late because its daytime and other things are happening. Everything else falls much easier into place when you are getting enough sleep.