- Start by lying flat on your back with an exercise ball under your heels. Bridge your hips up, and hold that position through the entire exercise.
- Flex your feet, and dig your heels into the ball. Place your arms straight out to your sides for support — don't use them, though; they are just for support.
- Slowly roll the ball toward your body as you curl your heels. Keep your hips in the bridge position; don't thrust them toward the ceiling as you do the move.
- Then slowly return to the start position (straight legs, hips bridged) to complete one rep.
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