Did you know that the abdominal muscles are designed to protect the lumbar spine against disk problems? It’s a paradox then, that in our ab-obsessed culture, so many of us suffer from low back pain—and in particular, disk herniation among the lowest vertebrae. You might think that toning your abs would lead to fewer back problems, but unfortunately, that is often not the case. Sit-ups and related exercises strengthen only one set of abdominal muscles, the rectus abdominis, which have little to do with the health of your spine.
Although most yoga postures don’t emphasize exercising the abdominals exclusively, a number of asanas work the full set of your abdominals to stabilize and support your lumbar spine, thus preventing disk problems and other forms of lower back pain.
The abdominals are one of your only significant lines of defense against wear on the lumbar disks. They offer protection in two ways: by limiting excessive rotation of the lumbar spine and by controlling the tilt of the pelvis and, thus, the curve of the spine. But before you hit the mat and start doing crunches, read on.
The abdominals are comprised of four paired muscles: rectus abdominis, the internal obliques, the external obliques, and the transversus abdominis.
The strap-like pair of muscles often admired in the form of a “six pack” is your rectus abdominis. Most of the popular ab exercises—curls, crunches, and sit-ups—target the rectus abdominis, but the rectus abdominis does little to support and stabilize the spine. When overdeveloped, this pair of muscles pulls down on the rib cage, rounding the upper back and creating tension in the shoulders, upper back, and neck. This imbalance can compromise the action of the other abdominal muscles—the ones we need in order to maintain a healthy back.
Believe it or not, the most important abdominal muscles for postural integrity are the obliques. The external obliques, which provide the most protection against the stressful rotation of the lumbar spine, are located on either side of the rectus abdominis.
They attach to the seven lower ribs and to the hip bones. When you move your ribs in one direction and your pelvis in the opposite direction, the external obliques limit how much the lumbar spine twists. They also help control the pelvic tilt. By tilting the pelvis back (posteriorly), they can reverse an overly arched lower back.
The transversus abdominis is the deepest muscle, running horizontally around the waist. Like a girdle, it pulls in on the belly and waist on all sides, providing overall support. The transversus abdominis is activated when you pull your navel back toward the spine or when you cough.
Working Towards Ardha Navasana
Start by lying on your back, with your knees bent and both feet on the floor, hip distance apart. Your thighs should be at a 45-degree angle to the floor. Press your lower back into the floor by firming your lower belly below the navel. Place your fingers on your lower abdomen to make sure that your abdominal muscles (and not the muscles at the front of your hips) are doing the work. (Here’s a hint: if you’re tightening your hip flexors instead of your abs your neck will tighten as well).
Extend your right leg at about 45 degrees from the floor, keeping the big toe and kneecap pointing straight up toward the ceiling. Lower your right leg only as far as you can while keeping your lower abdomen firm and your lower back pressed into the floor.
The weight of your leg will pull at your pelvis; use your external obliques to resist that pull. Work back and forth, alternating legs. Be sure not to take your leg down so far that you begin to lose the firmness in the abdomen or allow your lower back to arch.
If that was easy, try lying on your back with your thighs perpendicular to the floor. Bend your knees to 90 degrees, as if your feet were resting on a chair. Firm your lower belly again, pressing your lower back to the floor; press the backs of your ribs down as well. Extend your right leg out at 45 degrees and lower it, keeping the lower back and middle ribs grounded. Alternate legs.
For a full expression of ardha navasana, extend both legs straight up toward the ceiling. First, alternate lowering the legs one at a time as in the previous exercises.
If that feels okay, come into the full pose: lower both legs to about 30 degrees from the floor, with your big toe mounds touching, your inner heels apart, and your inner thighs firm.
Extend your arms forward and then curl your upper body up, keeping your sacrum and mid-back pressed into the floor from the firmness of your abdominals.
Bend your knees, release your upper body to the floor, and bring your legs back to vertical. After two to three repetitions, hug your knees into your chest. Relax!
Repeat this sequence for the next few weeks! And get prepared for part II;-)