Peyton Manning: The cerebral part of the game is the most challenging part of the game. You wouldn’t be in the NFL if you didn’t have the physical skills. I’ve spent tons of time, like I said, the workouts as a high school kid, lifting weights, running by yourself. You do that, but you have to do that. The cerebral part is where you can advance yourself and (what you) have to constantly stay on top of. Both of them, really. If you ever stop working out, that is when you get injured, you get behind. But you have to stay so sharp mentally. I think sometimes you can get away with the physical part with being a great athlete. I can overcome that, but the cerebral part, you can’t get behind in the mental aspect of the game. Everything happens so fast.