Get into a pushup position with your feet up on an exercise ball. Maintaining a straight line from head to toes, slowly draw your knees toward your chest, rolling the ball toward you.
Keep your hips down. Pause, then extend your legs, rolling the ball back even farther so your hands are 3–4 inches in front of your shoulders.
TWISTING EXERCISE-BALL KNEE TUCK :
Get into pushup position with your shins up on an exercise ball. Keeping your legs together, slowly roll the ball forward by bending your knees. Draw your knees as close to your right elbow as you can, pause, then extend your legs back to the start. Alternate sides for reps.
