HOW: Start by sitting upright on a swissball. Engage your core and begin the pelvic tilt by arching your back and rotating your hips backward. Then, round your back bringing your hips forward. Move back and forth between the two motions. The more your knees are bent up the harder the tilt will be. Try to move the ball back and forth with just your hips!
FEEL: You should feel your core, low back, and hip muscles working.
COMPENSATION: Don’t move your whole body as you tilt forwards and backwards. Use only your low back and core muscles.