http://AskTheTrainer.com/stability-ball-exercises.html Personal Trainer Michael Behnken, MS, NASM-CPT-PES, CSCS The stability ball toe raise should be more accurately described as the hip raise, as the raising of your hips is the abdominal contraction. It is best to use one of the smaller stability balls for this exercise. Make sure your knees and toes are aligned and your not in a knocked-kneed possition. For the advanced, eliminate the forward motion of the legs, keeping your feet straight up in the air for the duration of the movement. Lower yourself as slow as possible if you like burning abs. http://AskTheTrainer.com