Sit on a mat and place a stability ball between your legs (at your calves/ankles). Squeezing the ball in place, lie back onto the floor, keeping your feet just off the ground, knees bent. Make sure your lower back stays planted and your abs are tight. Place your hands lightly behind your ears in a crunch position.
EXHALE: Simultaneously lift your shoulders off the ground and your knees into your chest to perfom a double crunch.
INHALE: Slowly return to start to complete one rep.
Don't let momentum swing your knees up for you. Be sure your hands are not lifting your upper body-- concentrate on using abs.
Muscles Worked: Abs