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.
This abdominal exercise is about maintaining strength and control throughout a twisting motion. Your shoulder endurance will also come into play during this one as you are forced to maintain a completely stable upper body during a very dynamic lower body and hip movement. Keep the movement controlled and you'll see results.
With your body in a modified plank position, place your hands on the floor and a stability ball under your shins. Your knees and hips should be bent at right angles (see Photo 1).
- From the starting position, slowly twist and lower your hips to one side (see Photo 2).
- As you lower your hips, the stability ball should roll so that you end the exercise with your feet on top of each other and the side of one calf flat on the ball. Be careful not to go too fast—you do not want to tip off the ball, or let it shoot away. The position of your upper body should not change (see Photo 3). The more you keep your hips over your knees, the easier the movement will be.
- Return slowly to the starting position and repeat the exercise with your hips going the other direction. Alternate skiers for a total of 16 (8 on each side).