SETUP: Lie flat on the ground and grab a Swiss ball between ankles and arms overhead. Keep a slight bend in your knees.
REP: Raise your legs to beyond the line of your hips, and crunch your upper body, reaching to grab the ball in your hands. Immediatley return to an extended position with the ball in your hands, then perform the rep again but this time switch the ball back to your legs.
TIP: This is a fantastic abs exercise, but get some space in case the ball bounces off!