A wide varitey of exercises are recommended for the abs, and I did most of them throughout my bodybuilding career. But in terms of getting the best results for your efforts, one basic ab movement is the most effective: the crunch. The abs have one simple function: to pull the ribcage and the pelvis together. They aren’t attached to the legs, so when you do sit-ups and leg raises you primarily involve the hip flexors, and the abs have only a secondary, stabilizing function — unless, of course, you’re crunching your ribcage and pelvis toward each other. So whatever else you do to develop your abs, some kind of crunching movement should be central to your efforts. I recommend these exercises:
Lie faceup on the floor or a flat bench with your feet either flat on the surface or up in the air with your knees bent about 90 degrees. Cup your head lightly with your hands or fold your arms across your chest, whichever feels best. This exercise involves a short range of motion: Just contract your abs to pull your upper body toward your knees, then slowly lower back to the start. To ensure proper form, press your lower back into the bench or floor as you crunch up.
As the name implies, this is a variation of regular crunches. Lie faceup on the floor or a flat bench and draw your knees in close to your chest; this is the starting position. Contract your abs to lift your pelvis up and roll your knees toward your forehead. Squeeze at the top for a count, then slowly lower back to the start. This move is more intense because you add the weight of your lower body.
Lie face up on the floor with your legs straight. With your fingertips supporting your head, keep your elbows out to your sides. Next, raise your legs about 6 inches. Slowly curl your upper body off the floor, lifting your shoulder blades as your raise your chest and shoulders toward the ceiling. Simultaneously bring your knees toward your torso to meet your elbows in the middle of the crunch. Slowly return to the start position, keeping your feet off the floor at the start of each rep.
Unlike other muscle groups, abs benefit greatly from sets of very high reps. When asked how many reps he did for abs, Muhammad Ali once responded, “I don’t know — I don’t start counting until it hurts.” Try this crunch-focused, high-rep ab routine either after your next regular workout or as a stand-alone ab session. - FLEX