3/4 Sit-Up vs Exercise Ball Crunch

Lie down on the floor and secure your feet. Your legs should be bent at the knees.

Place your hands behind or to the side of your head. You will begin with your back on the ground. This will be your starting position.

Flex your hips and spine to raise your torso toward your knees.

At the top of the contraction your torso should be perpendicular to the ground. Reverse the motion, going only ¾ of the way down.

Repeat for the recommended amount of repetitions.

Lie on an exercise ball with your lower back curvature pressed against the spherical surface of the ball. Your feet should be bent at the knee and pressed firmly against the floor. The upper torso should be hanging off the top of the ball. The arms should either be kept alongside the body or crossed on top of your chest as these positions avoid neck strains (as opposed to the hands behind the back of the head position).

Lower your torso into a stretch position keeping the neck stationary at all times. This will be your starting position.

With the hips stationary, flex the waist by contracting the abdominals and curl the shoulders and trunk upward until you feel a nice contraction on your abdominals. The arms should simply slide up the side of your legs if you have them at the side or just stay on top of your chest if you have them crossed. The lower back should always stay in contact with the ball. Exhale as you perform this movement and hold the contraction for a second.

As you inhale, go back to the starting position.

Repeat for the recommended amount of repetitions.