I am a Jazzercise instructor. It's really fun and a great workout. It's dance aerobics with choreographed routines to all different music. A regular class usually is 30-40 minutes of aerobics and the remainder is muscle work and stretching. Classes are usually 1 hour. You can try your first class for free. To find a class near you go to
www.jazzercise.com and click on find a class.