Variety! If you are as old as me you remember the old step classes where about 30 people in unison did the same workout. It was a well thought out program that looked amazingly choreographed. These days the concept behind group fitness has changed a little. sure you can still do that same kind of class where everyone is doing the same thing or you can try a class where you use several different stations to mix it up. Much like a circuit. Circuit classes started off as weight machine classes where clients went from machine to machine in order to get a full body workout. Now, these classes resemble obstacle courses. In Austin Fitness Extreme I take that circuit concept and blow it up a little. If you look at this picture you can see the varying exercises that half of the class is doing.