Come into a side elbow plank on your right side, with your feet stacked one on top of the other. Keep your weight on your right elbow, with your fingers reaching away from your body.
Place your left arm behind your head and inhale to prepare.
Exhale and pull your navel to your spine, engaging your deep abs. Rotate your left rib cage toward the floor. Stay there for a second and deepen your abdominal connection by pulling your navel in toward your spine even more.
Return to the starting position and repeat. Repeat on your left side.