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Lay on your side with the exercise ball in between your feet. Lift the ball 4–12 inches (10–30 cm) off of the floor and hold it.
Use your calves and your shoes to grip the exercise ball between your feet. Using the arm that is closest to the floor, bend your elbow at a 90-degree angle and lay your forearm out so that it’s perpendicular to your spine. This will keep your frame stable as you raise the ball.  Wear shoes while performing this exercise. They will give you some traction to keep the ball still while you lift it. Put a yoga or workout mat underneath you so that your side doesn’t get sore. Use your other arm to balance yourself by putting your fingertips on the floor in front of you. Lift the ball and hold it in place for 2-6 seconds.