I don't know how Pattinson looks recently. Is he out of shape or just not jacked? I don't remember Keeton being jacked and he was just fine in the role. As long as he isn't shirtless in scenes, it really won't matter if he has a 6-pack or not. Bruce doesn't even have to fight probably. It will be Batman fighting. 2 words: Stunt Doubles. Batsuits are pretty good at hiding the actor in them. I'm sure every live action Batman has had other actors do stunts in place of the normal actor.