Zumba, the booty-popping, hip-thrusting, arm-waving dance exercise craze that has been sweeping the planet, was pure happenstance or a “happy accident,” as Zumba founder Alberto “Beto” Perez refers to it. Beto was ready to lead his step aerobics class in his native Cali, Colombia, when he realized he’d forgotten his usual exercise music. Rummaging though his backpack, he pulled out a tape (this was the mid-90s, okay) of salsa and merengue—sultry, saucy, syncopated tunes like the ones he danced to growing up. The fusion of sounds emanating from the boom box (yes, the giant, pre-iPod radio/cassette combo that gave you a workout just carrying it) resulted in a collective visceral reaction: moves and the overall energy in the room went from that of a basic workout routine to a full-on, beat-laden, midday rager. Beto knew he was onto something, but Zumba simmered until 2001, when another happenstance resulted in a business partnership that would eventually ignite Zumba fever worldwide.