Running and spine health. (The Clinic).

Does running compress the spine? Does running cause bulging disks and related nerve pain over time?

Francoise Dessange

Montreal, Quebec

The short answer is yes, running causes spinal compression. But, in rebuttal, that is not really a bad thing. Running intermittently compresses the spine as the weight of the body above any one segment of the spine comes down upon the lower segments when your feet hit the ground. However, intermittent loading is beneficial in that it stimulates bone mineral deposition, which can be helpful in building bone mass and preventing osteoporosis.

The intermittent compression from running may also be beneficial in preventing the problems from bulging disks that you've raised in your question. The intervetebral disks are what separate the vertebral bones, of the spine. It is what allows our spine the great degree of mobility in bending forward, backward, sideways and twisting. American Running Association Board Member, Lewis Maharam, M.D., suggests the analogy of a jelly doughnut for these structures. The outside of the disk is a fibrous substance called the annulus fibrosus. The annulus is like the doughy part of the doughnut, which holds a jelly-like substance called nucleus pulposus. The nucleus pulposus, like jelly in the doughnut, is a gelatinous substance containing a large amount of water. If it squirts out of the annulus fibrosus, it is a herniated disk that can be painful. Or the annulus can bulge (a bulging disk), which can be painless or painful. When you age, the amount of water in the nucleus pulposus decreases causing the other joints in t he spine to bear too much of the weight of the body and the impact of running, which can result in degenerative joint disease (osteoarthritis) of the spine. The intermittent loading of the intervetebral joints causes water to move out and in of the nucleus and may even retard the development of degenerative joint disease. If the spine is functioning normally, running can be good for your spine.

In order to keep the spine functioning normally, the structures that support the column must remain strong enough to do the job. Spinal stabilization exercises can help strengthen the muscles that keep the spine stable. Here are a few to repeat daily for muscular endurance.

* Abdominal crunches--a bent knee "sit up" in which you raise your body only high enough to get your shoulder blades off the ground.

* Abdominal hollowing--to strengthen the transversus abdominus, pull your belly button toward your spine.

* Lateral bridges--lying on your side, lift your body using one forearm, keeping both feet on the ground.

* Dog pointer--on all fours, lift up the opposite arm and leg, pointing them out, away from the body.

Stephen Perle, D.C.

Bridgeport, CT