India, Oct. 10 -- Stand outside a Zumba class, and you feel the vibe well before you see anyone sweat salsa, cumbia, merengue, reggaeton. People laugh, miss a step, and pick it back up. It looks like a party, so many assume it can't be proper exercise.

"As a certified fitness professional, I see people stay in a Zumba class for a full hour without checking the clock. They don't feel like they're exercising, and that's exactly why it works," Mr Rahull Raghuvanshii, Certified Fitness Professional and Managing Director, Jetts Fitness, tells Health Shots.

Songs in a class swing between fast and slow, so heart rate climbs and drops again and again, much like interval training. Squats, lunges, and side steps work the legs and glutes. Hip move...