As somebody who works out a lot, this idea does not appeal to me. I put myself in the shoes of people who attend aerobics and cycling classes (I strictly do free weights and the occasional cardio machine). And even then, I think this would be a turnoff to them. Yes, they like the encouragement of having an instructor and the pressure of keeping up with their classmates. But generally they would be turned off by having to compete against another team. It might sound sexist, but a lot of the people who attend classes at my gym are women and there is more of an air of the class being like schoolyard skipping rope than competitive team sport. The focus is on cooperation amongst the team itself, but not in an effort to beat some opponent.