I don't think it's really about being sporty, I think it's more about being in shape.
Most girls appreciate a guy who is in shape with muscles. It's the truth no matter what. Muscles are hot and they make a guy look sexier! Plus they show that he's strong. I think what can be attractive about sporty guys is that they are hard workers, competitive, and ambitious in a way because they have to be if they want to be good at their sport. Especially football players! They just seem to have this sexy, intense confidence about them!
I think this is hard to answer as everyone has their own view of what attractive is. Muscular guys can be nice to look at... but that body type isn't my fave choice. I prefer guys who are healthy with some fat/meat on their bones.