Stiletto Workout ? Now I have seen everything.

While you'll find most of these unusual classes at gyms in large cities, not all these new workouts have the same appeal everywhere. Whipped, for example, is a class taught by a strutting, leather-clad dominatrix brandishing a riding crop. It took off in New York but fizzled in mellower Los Angeles.

Stiletto heels are used in the new Stiletto Strength class. "It's a class all dedicated to the lower body and having great legs," explained Hogan. "It's a lot of sculpting and lower body workout and we supply the stilettos."

And if your local gym doesn't offer these classes yet, don't fret it might soon."We start a lot of things here [at Crunch] and eventually someone gives us the sincerest form of flattery," Hogan said of imitators. "Cardio striptease just celebrated its five-year anniversary, and it's all over the country now."