Flowing is a relatively new brand fitness that has you chaining together a sequence of exercises, doing one move, then seamlessly shifting to the next and then the next after that. Imagine doing a kettlebell swing, followed by a clean, followed by a snatch, followed by a squat-to-press. It’s like dancing with weights, and it draws from more venerable disciplines like yoga, gymnastics, martial arts, and breakdancing to do more than mere rep after rep of an exercise.

It’s also incredibly demanding on both your cardiovascular system and your strength, challenging you to move quickly and athletically while handling a weight (although it can be done with bodyweight as well). The result: You wind up breaking a fierce sweat as you build strength and athleticism. Flows do require more fitness experience than many kinds of cardio, because you’ll want to flow only with exercise moves that you’re comfortable with. But once you master enough exercises and get comfortable with several flows, you’ll find yourself getting a total-body burn and burning serious calories all at once.