What is the difference in ATP levels in zombies and Frankenstein-like monsters and regular people?
This question is difficult to answer since current scientific investigations are not looking in the directions of zombie or frankensteinien metabolism.
Presumably, since both zombies and Frankenstein can move, they have some type of ATP recycling metabolism. That is, their muscles require ATP to move and they are able to work their muscles so they must have some level of ATP somewhere near but likely lower the level of ATP used in a human.
People only have a few grams of ATP in their body to recycle, but the rate of ATP cycling is dependent on the overall level of metabolism. So really a better question is who cycles their ATP faster. Probably zombies, since they dont sleep just hunt for brains.
Biologically speaking, death occurs when the level of ATP reaches zero. ie. all ATP is ADP or AMP. When Frankenstein was reawakened he must have had a surge of ATP formation. Same thing with zombie awakenings. Otherwise the whole thing doesnt work out biochemically. Assuming that zombie, Frankensteinien, and human metabolisms are all the same.