• You need Flash player 8+ and JavaScript enabled to view this video.

Single Medicine Ball On the Shelf Crunches

By RealJock Staff

This exercise provided courtesy of Billy Polson, founder and co-owner of DIAKADI Body training gym, voted best personal training gym in San Francisco by CitySearch in 2006.

Add the medicine ball to a classic abdominal crunch to get an extra punch. Alternate holding the ball in your hands and with your legs to push both your upper and lower abs to the limit.

Muscles Worked

Starting Position
Lie on your back on the floor and bring your legs up into the air such that your hips and knees are bent at a 90-degree angle. You should try them first without wall support, but if they are too difficult for you and you feel you need to, you may rest your feet flat against a wall for support, as shown in the photos accompanying this article. Your thighs should be vertical and your calves parallel to the floor. Keep your feet together. With a medicine ball in your hands, bring your arms overhead until they are resting on the floor above your head, fully extended (see Photo 1).


  1. From the starting position, bring your arms directly up and forward over your body as you bring your shoulders off the floor. At the top of your lift, place the medicine ball on your legs, cradled between your shins and your shoe laces (see Photo 2).
  2. Leaving the ball resting on your legs, lower your upper body back to the floor, keeping your arms extended and bringing them overhead as you lower your shoulders back to the floor. You will end up back in the starting position, but with the ball now resting on your feet (see Photo 3).
  3. With the ball still resting in the pocket of your shins and feet, again raise your arms up overhead and bring your shoulders off the floor in a crunch. At the top of your motion, grab the ball back in your hands, and once again lower to the floor, now with the ball again in your hands (see Photo 4). Continue performing crunches, swapping the ball between your legs and hands, until you have completed 20 transfers for a full set.
About Billy Polson: Billy Polson is the founder and co-owner of DIAKADI Body training gym, which was voted the best personal training gym in San Francisco by CitySearch in 2006. A competitive swimmer and triathlete in his own right, Polson has over 15 years of experience working as a coach and trainer, and was recently named by Men's Journal Magazine (December 2005) as one of the Top 100 Trainers in America.