The key to keeping your abs working during this move: maintain strong posture by pressing into the ball with your forearms, squeezing your butt, and engaging your legs.
Kneel in front of a stability ball with your forearms and elbows on the ball, hands clasped. Roll ball forward to extend legs and form a forearm plank position on the ball, toes tucked. Your shoulders should stack directly over elbows, chest lifted off the ball, and neck in line with spine. Brace your abs and slightly tuck pelvis forward. Make small circles to the right with forearms, as if stirring a pot. Keep hips steady. Go for 20 to 30 seconds in each direction.