A number of popular workouts didn't make this list. Here's why: In order to make sure we were comparing apples to apples in making this ranking, we exclusively used data from a single, sweeping review of exercise science.
There simply isn't a dataset more thorough or well-grounded out there, and we didn't want to muddle this one up by introducing numbers obtained using different methods, from branded advertising or without exact comparisons.
That said, it's worth keeping in mind that there are plenty of ways people love to exercise that aren't among these 36. Here are a few, along with the calories per hour counts that have been attributed to them.
Take these numbers with a grain or two of salt, especially when comparing their numbers with numbers from the peer-reviewed comparative research.
SoulCycle/Spinning: The stationary-bike-class company has its issues, but reports that its attendees can expect to burn 500 to 700 calories in a session. This tracks closely with other data on stationary cycling.
Pilates: We found only one 2005 publication offering anything like science on the calorie efficiency of pilates (though it appears to have been published without normal peer review). It claims pilates burns 4.0 to 7.5 calories per minute. Assuming this translates over longer time spans, that's about 240 to 450 calories per hour.
Zumba: A Zumba-funded study conducted on young, healthy women found that a single 39 minute Zumba class burns an average of about 360 calories.