You don't see a lot of black swimmers, hockey players, divers, speed skaters, curlers, from the testaments of my black friends, " because we hate the cold and we can't swim."
I'll try to more fully address some of the... thoughts expressed here later, when I'm not at work.
But I did want to say that the idea of accessibility has a lot to do with who participates in Winter Olympics. Arthur Ashe used to talk about it, regarding the lily-whiteness of tennis. Because of people like him, we have the Williams sisters and a couple of others. Because Tiger Woods has made conscious efforts to open training facilities in areas which otherwise would never see a putting green or a 9 iron, the upcoming generation will probably have more darker complected folks walking up fairways.
Conversely, without at all buying any notion of racial superiority, I don't know of anyone who will argue the fact that blacks excel at basketball and the other two major selling sports in the US. That isn't because there aren't enough basketball goals in the suburbs. It's an interesting subject, and its too easy to start throwing accusatory bombs prior to looking at the whys and wherefores.
I gotta admit it amuses the hell out of me how nasty some folks will get right out of the chute - they can't even pretend to have expansive attitudes in matters of race, so if challenged, they simply start making juvenile jokes and accusing me of having no sense of humor.
I submit that no one possessed of intelligence and integrity at A2K can deny that race and sports (also race and politics, race and relationships, race and intelligence...etc) has potential to provoke not just defensive trading of barbs, but also some worthwhile contemplation.