To get into the starting position, lie on your back with a stability ball above your ankles. Now press your hips up until you are in a face-up plank position with shoulders, knees and ankles all forming a straight line. From here, with control, slowly curl the stability ball toward and underneath you, then return to the starting position and repeat.

To get into position, start with the ball under sternum and chest and then walk your hands forward on the ground until the ball is under your chins. Hands should be directly underneath shoulders. To initiate movement, pull your belly button in to your spine, then draw your knees to chest. Move with control forward and back. If you start to feel your spine/stomach drop, stop and rest before finishing your set.