Another great article by:
Gretchen Reynolds on the science of fitness. NY Times
Lower back pain is an almost universal if unwelcome experience. About 80 percent of those of us in the Western world can expect to suffer from disruptive lower back pain at some point in our lives. But if we begin and stick with the right type of exercise program, we might avoid a recurrence, according to a comprehensive new scientific review of back pain prevention.
Lower back pain develops for many reasons, including lifestyle, genetics, ergonomics, sports injuries, snow shoveling or just bad luck. Most often, in fact, the underlying cause is unknown.
For most people, a first episode of back pain will go away within a week or so.
However, back pain recurs with distressing frequency. By most estimates about 75 percent of people who have had one debilitating episode of lower back pain will have another within a year.
These repeated bouts can set off what doctors and researchers call a “spiral of decline,” in which someone takes to his or her couch because of the pain; this inactivity weakens muscles and joints; the person’s now-feebler back and core become less able to sustain the same level of activity as before and succumb when he or she tries to return to normal life, leading to more pain and more inactivity; and the spiral accelerates.
This scenario obviously makes preventing back pain, especially in someone who already has undergone at least one episode, extremely desirable. But until now, few studies have systematically examined what really works against repeated back pain and what doesn’t.
So for the new review, which was published in JAMA Internal Medicine, researchers affiliated with the George Institute for Global Health at the University of Sydney in Australia and other institutions set out to gather and analyze as many relevant studies as possible.
There were surprising few high-quality studies, meaning those that had randomized participants to be treated or not. But after scouring through more than 6,000 studies about back-pain prevention, the researchers settled on 23 that they felt to be methodologically robust. These studies had examined, in total, more than 30,000 participants with back pain.
The prevention techniques under review included education about lifestyle changes, shoe orthotics, back belts, various types of exercise programs and exercise programs that also included some type of education about back-pain prevention.
For the purposes of the review, a successful prevention program was one that had kept someone from reporting another bout of back pain within a year or longer or that had staved off lost work time due to back problems.
Such success, as it turned out, was discouragingly limited. Educational efforts by themselves showed essentially zero ability to prevent a recurrence of back pain, the researchers found. Back belts and orthotics likewise were almost completely ineffective, leaving people who employed either of those methods very prone to experiencing more back pain within a year.
But exercise programs, either with or without additional educational elements, proved to be potent preventatives, the researchers found.
In fact, “the size of the protective effect” from exercise “was quite large,” said Chris Maher, a professor at the George Institute, who oversaw the new review. “Exercise combined with education reduced the risk of an episode of low back pain in the next year by 45 percent. In other words, it almost halved the risk.”
Interestingly, the type of exercise program didn’t matter. In some of the experiments that Dr. Maher and his colleagues reviewed, the regimens focused solely on strengthening the core and back muscles. In others, the training was more general, combining aerobic conditioning with strength and balance training. Most asked participants to complete two or three supervised sessions every week, typically for about two months, although some lasted longer. A few included education programs as well.
The end result was that if someone with a history of back pain exercised in a regular way, he or she was considerably less likely to be felled by more back pain within a year.
However, the protective effects typically wore off after that, with recurrences rising after 12 months, probably because many of the people who’d been involved in the studies stopped exercising, Dr. Maher said, and their back problems returned.
So based on the currently available evidence, he said, it’s still impossible to know whether exercise improves back health in the long-term, or if one type of exercise program is measurably better than others. He and his colleagues hope to mount studies comparing different routines head-to-head and follow people for several years.
But for now, he says, “of all the options currently available to prevent back pain, exercise is really the only one with any evidence that it works.”
If you are curious about the particulars of an effective back-exercise program, Dr. Maher points to one example, a full regimen of exercises from a 1991 study in the journal Physical Therapy, one of the studies included in the new analysis. Its suggested workout soundtrack of 1990s Swedish pop tunes is, however, optional!