If you ever jumped rope as a kid, it probably never crossed your mind that you were burning calories, toning muscles, and improving your cardiovascular endurance. Knowing firsthand the benefits of jumping rope, Double Dutch world champion Michelle Clark is re-introducing the activity to adults—only this time, as a heart-pumping workout. During Michelle's classes, exercisers jump rope, of course, but they also perform jumping jacks, push-ups, and jump squats between the whirring strands. And though nostalgia may elicit plenty of smiles during class time, these jump rope-driven workouts still help participants work up a healthy sweat, kind of like if one of the strands was replaced with a huge anaconda.