If you're going to play a champion athlete, people expect you to look a certain way, and you also have to have the stamina to be able to continue to perform.
I would say that one of the really special gifts about playing an athlete is that it's the best motivation you'll ever have to get in top shape and stay in top shape because you know that you're going to be expected to deliver.
Not all television scripts are created equal. And the process is ridiculous. They send you a script and want you in the next morning. That's not how acting works. You can do anything to me as an actor; I'm a very resilient guy. Just don't rush me. If you ask me to do it immediately with no time to prepare, I know you have contempt for actors.