There is nothing more impressive than a beautifully defined arrangement of abdominal muscles. It's amazing how simple anatomy is responsible for something as sought after as the elusive six-pack.
The rectus abdominus is a long flat band of muscle fibers running vertically from the fifth, sixth and seventh ribs down to the pubic bone. A long flat tendon called the linea alba divides the large muscle into left and right halves. It is the three horizontal grooves dividing the muscle into the much-coveted eight-pack that give the tummy a washboard appearance - if your nutrition and training allow. This large muscle is responsible for flexing the spinal column and bending the body. The external obliques are abdominal muscles located on either side of the rectus abdominis and the internal obliques run at right angles to these muscles. These muscles help us flex the rib cage and pelvic bones.
The muscles that have nothing to do with abdominal musculature but keep popping up at the wrong time and fooling us are the hip flexors. These muscles bring the legs and trunk toward and away from each other. Many people think when they are doing sit-ups they are working their abdominal muscles, but often what happens is they wind up working the hip flexors instead.
Is isolation possible?
One common question is, "Is it possible to isolate just the upper or lower abs?" Often when training, a strenuous effort is made to focus on either the upper or the lower abs even though the abdominals are one giant slab of muscle fed by the same supply of nerves. When you train abs, every segment is involved to a lesser or greater degree but you can perform certain abdominal exercises that focus on the lower abs more so than the uppers. So the answer is "yes."
Heavier weights, better abs?
There is something to be said for adding resistance to your ab moves. The extra weight delivers a more intense workout to the unsuspecting muscle. Using resistance requires you to concentrate more on your technique, which should therefore be perfect before you attempt any weighted exercises. You will need to put your mind into the muscle before you load up. As you exert yourself don't rush the workout, but perform each repetition with control.
Chase it with clean eating
No amount of isolated lower abdominal training will pull your lowers into view if you don't follow up with clean eating. Lean protein from a variety of meat and meat alternative sources, complex carbohydrates from fresh fruit and vegetables and whole grains, all chased with plenty of water, is the perfect ab-defining recipe.
Add these next five moves into your routine, and you'll get that flat stomach in no time!
Target Muscles: rectus abdominis
Synergist Muscles: obliques
Set Up: Lie supine on the floor with your knees bent and your feet flat on the floor. Place your fingers lightly behind your head for support; do not pull on your head. Allow your elbows to flare out from your ears.
Action: Exhale and curl up, shortening the distance between your ribcage and your hips, lifting your head, shoulders and upper back off of the floor. Slowly lower to the start position and repeat. Do three sets of 15 reps.