15-Minute Full-Body Exercise-Ball Workout
Move 2: Lower-Ab Crunch
Lie on the floor with arms beside you and calves on the ball. (A) Lift your backside up without arching your back (keep your abdominals tight for support). (B) With hips still raised, bend your knees and roll the ball toward you with your feet until they’re flat on top of the ball. Slowly return to the starting position. Repeat 15 times.