It depends on the individual client’s needs. However, in my opinion, the single best class for a client is the one they will attend AND return to.
That’s why Zumba, which doesn’t burn as many calories as other workouts, is so effective. Per Alberto Perlman, CEO of Zumba, in his key note address to instructors in 2015, retention rate for the typical bootcamp class is 4-7%. Retention rate for Zumba is 28%. So, even if an individual burns 100 more calories in a bootcamp than a dance class, if they don’t return to it, it’s not all that effective in a long-term sense.
I don’t send all my clients to Zumba. It’s not a good fit for everyone. That’s just an example of, find a class people will stick with, as opposed to “the most effective.”