The modified stability ball roll is a good alternative to the traditional ball roll exercise. The modified version is done in almost the same way as the regular method. The difference is that the elbows are bent during the roll-out. As a result, the back and arm muscles don't have to work as hard.

Begin with the knees on the floor and the elbows on the ball. Roll the ball forward while keeping your elbows locked into position. The abs should move toward the ball. The upper portion of the abs should come close to touching the ball. If needed, you can add stability to this exercise by interlacing the fingers so that the palms are together. In the full roll-out position, the butt should be down and the lower back should be flat. The elbows should remain bent in a fixed position. As the ball goes forward, the abs will contract. Return the ball to the starting position. Keep the midsection tight. Repeat the exercise.