ABS/CORE: V-UP With Ball Pass
Lying on your back, grip a exercise ball with your hands. Simultaneously raise and bring the arms and legs upward and together, pass the ball from the hands to the legs, now gripping the ball between the ankles as you lower the ball.
Repeat this action passing the ball back and forth for reps.
If discomfort is felt in the low to mid back, shorten the range of motion and focus on bracing the abdominal region.