This versatile and inexpensive prop is one of my favorites. You'll want a ball that is approximately 9 inches or smaller in diameter when fully inflated. I use the Overball, sold by OPTP (www.optp.com) in my Pilates classes, but you can use kid's balls sold at drugstores or sporting goods stores. Here is a sampling of exercises you can try.
WALL SQUATS WITH BALL
1. Press the ball between your lower back and the wall. Position your feet shoulder-width apart--weight on your heels, as if you were sitting in a chair. 2. Begin to descend, keeping your abdominal muscles tight and pressing your back into the ball as you roll it slowly down the wall. Descend until your knees are bent at a 90 degree angle. Hold for 5 seconds. Roll up to standing position and repeat 5-10 times.
INNER THIGH SQUEEZE WITH LEG EXTENSION
1. Sit in a chair with your back supported and your feet flat on the floor. Place a ball between your lower legs. 2. Lift your lower legs up until they are parallel to the floor. 3. Squeeze the ball for 5 seconds while you hold your legs up. Hold onto the side of the chair seat for extra support. Repeat 5-10 times.
BIRD DOG WITH BALL BALANCED ON BACK
1. Start with hands shoulder-width apart and knees hip-distance apart. Place ball on back. (Note: This is easier said than done. Feel free to try this without the ball, as it is a great exercise for the core with or without the ball.) 2. Carefully raise one arm and the opposite leg, keeping spine in a neutral position and hips and shoulders square. Hold. 3. Carefully lower hand and knee and switch sides. Repeat both sides.