Want sculpted abs? Nichelle Laus demonstrates the ball crunch.

Ball crunch exercise - Flat stomach & strong abs - Women's Health & Fitness

How to

Lie on the ball, positioning it under the lower back. Place your arms behind your head.

Contract your abs to lift your torso off the ball, pause, then lower yourself back down, getting a stretch in the abs.

Perform 3 sets of 15 reps.

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Photo credit: Dave Laus