It’s noon at the gym. Now, I don’t mean to pigeonhole anyone, but after 14 years in the fitness industry I’d bet if you looked around said gym, most of the female members will be found in the fitness or spinning or yoga studio enjoying an instructor-led class. Are those fitness classes really working for you? How many calories do they actually burn?

Fitness classes are a great way to add long cardio sessions to your repertoire, and sometimes (depending on the type) supervised strength training at a lower cost than working one-on-one with a trainer. But if you’re in the same step class Monday through Friday, or you know the spinning playlist better than your instructor, you might be overdoing it.

BB is a regular contributor to Erica Ehm’s Yummy Mummy Club. Find out how your fitness class compares to all the other types, and how many calories you’re REALLY burning…