Lay on your back, feet on the ball, pushing your heels into the ball. Your arms are on the floor at your sides. When you are stable, lift and lower your hips, keeping your balance and being sure not to bring them all the way to the ground. Keep the tension through your buttocks and stomach.

To make the exercise easier, span your arms out perpendicular to your sides.

For more difficulty, rest your hands on your chest, and for a further challenge, lift one-leg at a time in the air.

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