I've noticed men avoid these classes because tend to be a majority female attendance (at least at my gym). I do feel like the classes are also geared towards women, but that could just be me or my gym (they call is body-design). I'm not intimidated by that, but I feel like many guys are.

I do these with my girlfriend usually, which helped get into it initially, but I'm often the only guy. Doesn't matter, it's a killer workout. Even though I lift, I still do classes like this each week for general fitness.