I don't think all atheletes are empty shallow people with mainstream interests. I played sports(baseball and football) in high school and I'm into all kinds of music, including forms of metal. But I do admit there seems to be a correlation between athletes and religiousness. Even on such a small-scale that I came from. Team prayers before every game for example was a normal thing for me. Now I think it's ridiculous, but that's part of the mainstream culture sports feed on. There has to be some NFL player into black metal or from some major sport.
By the way, in the recent boxing match between Kelley Pavlik and Sergio Martinez, Kelly came to the ring with Korn as his entrance music and Sergio with System of a Down as his music. That's about as metal as we're getting with sports.