Jazzercise: jazz + exercise
According to the Jazzercise Web Site, "Judi Sheppard Missett, who turned her love of jazz dance into a worldwide dance exercise phenomenon, founded the Jazzercise dance fitness program in 1969." from there, it has continually expanded into what is now Jazzercise, Inc.
I was surprised to learn that Jazzercise is older than I am, and even more surprised that that people are still doing it. I need to lose some weight; maybe I should give Jazzercise a try?