Well, I tried CrossFit for the first time yesterday. It took me about 30 minutes to get though the WOD (Workout of the Day). It kicked my butt! According to my Polar watch, I burned 300 calories in 30 minutes!
I'm pretty sore today. My friend who just now became certified in CrossFit said that she is always sore after every workout and she has been doing it for a year now. And let me tell you, she looks awesome!
I'm completely sold on it. However, CrossFit gym memberships aren't very cheap....