Come to a tall kneeling position on the ground and place an exercise ball in front of you. Brace your core as you place your forearms on the ball. Slowly roll forward with the ball until your shoulders are over it and your torso is tipped forwards. This is your start position. Keeping you core braced, proceed to make smal circular motions with your elbows thereby rolling the ball. Feel the contraction of your core as you move. Rely on your core muscles to help you maintain stability.