Well dunno if this will cross over to drumming but a good way to build your chops in guitar is to start with a metronome at a moderate speed, play a particular piece that you're learning, bump the 'nome up 2 clicks for a while then down 1 click for a while the nup 2 etc. 2 steps forward, 1 back if you will. Sounds odd but it works.
The other thing I do to get a hard piece down is to start with the first few notes (drum hits in your case), build up speed just cycling these few notes, then add 1 more note/hit to the end of the segment and work it for a while. Its sometimes called burst training.
My experience on the drums is minimal but I dont see why these techniques couldnt be applied.
I'll leave nutrition etc to Chad!! Ok I'll hazzard a guess - get the carbs in!
(I heard that with all his onstage antics Angus Young drinks a few pints of glucose during a show....)