Remember how fun it was in elementary school, jumping rope during recess? Though it might be tough to find willing double-dutch participants, going solo can still be a blast. It’s also a major toning exercise and calorie-burner, if you take the right steps. To engage all your muscles, including the smaller stabilizer ones, fitness guru Tracy Anderson says footwork is important: “Jump on one foot, jump side to side, jump with both feet, jump in a running pattern—the key is changing up the motion while keeping the heart rate pumping.”