Benefits: This core exercise does double duty by strengthening the hip flexors and crunching your abs.
- Get in a high-plank position with your hands directly underneath your shoulders and your shins on top of a stability ball.
- Brace your core to keep your body in a straight line from head to toes. This is your starting position.
- Squeeze your core and bend your knees to roll the stability ball toward your hands until only your toes are resting on the ball, keeping your hips down as you do so.
- Pause, then slowly straighten your legs back behind you, returning to the starting position.