I joined an aerobics exercise class twice and for sure it is harder then it looks. It depends on what instructor you have and how they run the class. From my experience with two different instructors, they both used a lot of cardio exercises like Zumba dancing. We did boxing (mainly with air not with targets), mini weight lifting, a lot of endurance training, and even something they like to call "bootcamp." It's multiple exercises that targets different group muscles that they spread out throughout the room and you rotate doing one by one on a limited amount of time for each section. It was hard but enjoyable. Try it and see if it's for you