Although toned abdominal muscles may look attractive, they actually serve a very important role in helping to stabilize the back. When abdominal muscles are strong they can help stabilize the pelvis and lumbar spine when the hips flex by preventing an increase in lumbar lordosis.

Contracting the abdominals, especially the deep inner muscles, causes an increase in intra-abdominal pressure. The increased pressure pushes out against the back which helps the back to stabilize itself. This is helpful in everyday activities from lifting objects to playing sports.

The anterior and lateral trunk muscles consist of four muscles. These muscles are large sheaths arranged in layers with fibers running in different directions. Together they are responsible for trunk flexion, rotation, lateral bending, and aiding trunk stability.

The rectus abdominis is the most superficial of the abdominal muscles. It originates at the xiphoid process and costal cartilages 5-7 and inserts into the pubic crest and symphysis. It is easy to see on a person with developed abdominal musculature, it is sometimes referred to as a "six-pack." The primary function of the rectus is that it acts as a trunk stabilizer and flexor.

The external abdominal oblique covers the abdomen anteriorly and laterally. This muscle originates from the external surface of the lower ribs and runs in a downward diagonal pattern as it inserts into the external lip of the opposite illiac crest. The muscle contracts unilaterally as it rotates the trunk to the opposite side.

The internal abdominal oblique helps to stabilize the trunk. This muscle lies under the external oblique, however the muscle’s fibers run in an upward diagonal pattern from the thoracolumbar fascia and the illiac crest to the lower three ribs and costal margins and to the pubis. This muscle contracts with the opposite side external oblique to rotate the trunk to the same side.

The transversus abdominis is the deepest of the abdominal muscles. The fibers which run in a transverse direction serve to enclose or compress the abdomen. The muscle originates at the lower ribs, thoracolumbar fascia, crest of the illium and inguinal ligament and inserts into an aponeurosis.

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Exercises

To train and strengthen the abdominal muscles so that they may help to stabilize the back and pelvis, different exercises consisting of different movements must be done to target each muscle.

Pelvic tilt

This exercise is a subtle movement that will teach you the correct position your back should be in when doing abdominal exercises. Begin by lying on your back on a mat with your knees bent. Tighten your stomach and flatten your back into the floor. Your feet should remain flat on the floor while you hold this position for six seconds. Slowly release and roll back to the original position.

1 set of 10

Crunch

Lie on your back on a mat with knees bent, feet hip width apart and flat on the floor. Rest your hands behind your head. Tighten your stomach and lift your shoulder blades off the floor. Exhale as you lift up and hold for a count of two. Slowly lower down to the floor while inhaling. Do not pull your head up with your hands, leave your fingers resting lightly on your head.

1 set of 20

Reverse curl/crunch

Lie on your back on a mat with fingertips behind your head. Raise legs in the air with hips and knees both bent to 90 deg. (shins should be parallel to the floor). Simultaneously pull hips off the floor while contracting abdominals in a slow motion. Hold for two seconds and release.

20 reps

Oblique twist

Lie on your back on a mat with both knees bent at a 90 deg. angle (shins should be parallel to the floor). Fingertips behind the head and elbows pointed out. Extend right leg out while pulling left leg in toward your chest. Simultaneously raise your shoulders and twist your trunk so your right shoulder approaches your left knee. Hold for one second then repeat with opposite side.

Alternate for twenty reps (2 twists equals one rep)

When doing these exercises be conscientious about your form and technique. If you experience back pain, these exercises may not be ideal for you and you should discontinue the exercises. Be conscious of your posture, whether sitting or standing, use your abs to keep your back straight.