Zumba was born in Colombia in the 1990s, quite by accident. A fitness instructor forgot to bring his usual workout music to class, so he grabbed some Latin albums from his car, ditched the constraints ...

At Zumba, there is a whole lot of shaking going on. Hands and hips jiggle, shoulders shimmy and feet fly back and forth. Faces are noticeable, too. They glow with a smile. “I never taught a class that ...