1. Lie face-up with the ball resting under your mid/lower
back.
2. Cross your arms over the chest or place them behind your
head.
3. Contract your abs to lift your torso off the ball, pulling
the bottom of your ribcage down toward your hips.
4. As you curl up, keep the ball stable (i.e., you shouldn't
roll).
5. Lower back down, getting a stretch in the abs, and repeat for
12-16 reps.
