It's called resistance training. The women are working two opposing muscle groups at the same time in a push and pull fashion.

It really clicked with that age bracket because of the time it takes, the fact there are no scheduled classes and the camaraderie of the women.

Curves' workout is 30 minutes, which Haven thought would get more women working out and living healthy.

What makes it really work is a women can walk in a any time and start their workout.