a) Bent crunches: Lie flat on the floor with the legs over a bench so that the thighs are perpendicular to the floor. Cross the arms over the chest or hands behind the head. Once you are in the proper starting position, simply raises your upper back off the floor very slowly and roll forward until you reach the end point of the movement. b) Hanging leg raises: Take an overhand grip on a pull-up bar with your hands  about shoulder-width apart and allow your body to hang freely. Keeping your legs straight and toes pointed, exhale and slowly lift your legs upward, avoiding the use of momentum until your body forms an ‘’L’’ shape in mid-air. Pause a moment before slowly lowering your legs back to the start.   c) Pull-down/Cable crunches: Use the rope attachment on the high cable pulley. Kneel facing the machine and grasp hold of the rope and put your hands against your forehead. You then begin the exercise by slowly moving your body downwards in an arc, rounding your back and trying to get your elbows to touch your knees. Contract for 2 seconds hard before retuning to the starting position. d) Swiss ball crunches: Balance yourself on an exercise ball with your arms folded across your chest or behind your head, your focus on the ceiling and your feet flat on the floor. Your starting position should find your back slightly arched over the curve of the ball. Exhale and slowly lift your upper body off the ball, keeping your focus high and your elbows wide. Pause a moment in the topmost position before inhaling and slowly lowering yourself back to the start. e) Swiss ball vertical crunches: Position a bench near the swiss ball so you be able to grasp it. Lie on the ball with your hands over your head gripping the bench behind it, your back flat and your knees bent and held above your hips. This is your starting position. From here, slowly curl your knees up and in toward your head, lifting first your tailbone, then your hips, off the ball. When your knees come to eye level, reverse the motion and slowly uncurl. Pass the start position and extend your legs straight out and away from you, keeping your back stable on the ball and your shoulders down. Squeeze for a moment and come back to the start. f) Swiss ball side crunches: Lie on a swiss ball, place your feet on the floor, knees bent and spread your legs so your feet are slightly more than shoulder width apart. Slowly raise your upper and mid back off the ball and turn to your right so you are in an oblique curl position. Squeeze for a second and then slowly return to the starting position.