What do they all have in common?
I'll give you one hint: it isn't that they spent six hours a day in the gym getting these physiques; there's no time to do that - not with the enormous amount of skills one must acquire that are specific to baseball and tennis.
Spend six hours a day in the gym, and you won't have the skills necessary to play these sports.
Spend six hours a day practicing these sports, and you won't have these physiques.
This post is dedicated to Lance Armstrong.