2A Alternating Swiss-Ball Leg Curl
Sets: 2-3 Reps: 10 (each leg) Tempo: 212 Rest: 60 Seconds
Lie on your back on the floor and rest your legs on a Swiss ball. Straighten your hips so that your body rises into the air , raise one leg off the ball, and bend the opposite leg's knee so that you roll the ball toward you (the movement is similar to a hamstring curl on a machine) . Straighten your knee again and switch legs, this time rolling the ball with your other leg. That's one rep.