Exercise: Supine Heel Lifts with the Exercise Ball

Roll a stability ball to the middle of a gymnastics mat. Lie down with your back on the mat, and roll the ball under your lower legs. Both lower legs are parallel to the floor, knees and hips are bent approximately at 90 degrees.

Keep your arms are next to your body. Keep your abdominals engaged while you lift your right leg off the ball without changing the position of the spine. Press your left leg firmly into the ball, hold for seven to ten seconds.

Switch legs, now pressing the right leg into the ball. Return to start position. Start with 2 sets of eight to ten repetitions.

Source: http://www.fitness.com/exercises/389/supine_heel_lifts_with_the_exercise_ball.php

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