You definitely won't lose any significant muscle mass in 24 hours. If you aren't accustomed to it, the cravings will be a struggle, but it's definitely doable.

I'd suggest finding a spot in your schedule where you're going to have a very busy morning through afternoon. Eat an early dinner the day before, then just don't have anything to eat or drink before you start that busy day.

I'm doing them for the sats and hoping it becomes a normal routine. It's miserably cold here, right now, so left to my own devices I wouldn't be nearly as active.