Lie face up on slant board, knees bent with feet under pads. Keep neck straight. Cross arms over chest. In a controlled motion, keeping neck straight, curl upper body up. Contract abdominals fully without compromising form. While maintaining the controlled motion, return to starting position. Do not allow muscle to relax before next repetition.
Here are a few suggested alternative exercises:Ab CrunchAb Crunch ObliquesBall Crunch TraditionalDouble CrunchDumbbell Side BendsLateral Bend with Barbell