Aerobic Fitness and Chronic Low Back Pain Don't Add Up
Exercise therapy has been shown to help patients with chronic low back pain (LBP). Researchers are raising questions about the connection between aerobic fitness and pain intensity. Will back pain ease as aerobic fitness improves? If so, are the improvements in pain a result of being more aerobically fit? Finally, does being aerobically fit lessen the intensity of pain in people with chronic LBP?

These and other questions have been studied by a group of doctors and physical therapists. Earlier studies showed that using a treadmill is best for testing aerobic fitness. The amount of oxygen used at each level of exercise is measured. This is called VO2max and is a measure of aerobic fitness. Aerobic fitness tells how well the heart and blood vessels are working.

The researchers measured several items besides pain. They also looked at age, sex, job status, and level of disability. None of these had an effect on pain. Only educational level made a difference. Patients with less education had more pain. The amount of pain medication used before and after the exercise program didn't change. The patients were able to walk for a longer time at the end of testing.

According to this research, there doesn't seem to be a link between aerobic fitness (as measured by VO2max) and low back pain. In other words, being out of shape doesn't appear to increase back pain. The reverse is also true: being aerobically fit doesn't protect anyone from feeling more back pain during exercise.

Since it's known that exercise can have a positive effect on low back pain, these new findings are important. The results of this study indicate that aerobic exercise to condition the heart and body doesn't necessarily change the level of pain. Clearly, more research is needed to find out what kind of exercise is best.
Harriët Wittink, PT, PhD, et al. The Association of Pain With Aerobic Fitness in Patients With Chronic Low Back Pain. In Archives of Physical Medicine and Rehabilitation. October 2002. Vol. 83. No. 10. Pp. 1467-1471.