I've started watching Fighting Spirit (Hajime No Ippo) from the first season, and this is a pretty good sports anime - particularly focused on Boxing. From the little bit of peeking ahead that I've done, there aren't particularly any super-powers in the show (as opposed to stuff like Prince of Tennis), and the show does a really good job of explaining the fundamentals of boxing. I'm not going to say that the show is going to inspire me to take up boxing (my pain tolerance is too low for that). However, I think if I watched a boxing match on TV, I'd probably have a better appreciation of what's going on.
Also, I know one of the games based on the show got a stateside release under the title of "Victorious Boxers". I'm tempted to see if I can find a copy and pick it up. Has anyone played it? If so, how is it?