Myotatic Crunch
Lie on the BOSU ball, positioning it comfortably under your lower back. You'll get a better stretch in your abdominals while keeping your lumbar spine safe and comfortable.
Plant your feet with your knees bent.
Reach your arms over your head and lean back until you feel a good stretch in your abdominals.
Lift your shoulders up by slowly contracting your abs.
At the top, contract your abs as tightly as possible while exhaling, then slowly lower yourself back to the starting position.
Both the lifting and lowering should be very controlled, with a few seconds spent contracting and relaxing.

Muscle group: Abdominal

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