Lying face down on a mat, get into pushup position. Keep shoulders, hips and knees in a straight line/plank position. Place hands directly under the shoulders, space hands just wider than shoulder width apart. Place your feet on a stability ball, the ball should rest comfortable on shins between the knees and ankles; pull navel in to stabilize the core, don’t drop the hips. Inhale; bend the knees and pull them into the chest, rolling the ball from the shins to the top of your shoes. Contract the core to help stabilize throughout the movement. Inhale; slowly roll the ball back down to the shins, body will return to plank position. Keep the core engaged at all times and don’t allow the hips to drop below the shoulders. Repeat.