The overweight women who exercised an hour or more a week, however, were less likely to get the condition than were overweight women who were inactive.
Mork's advice: Regular exercise, which can help maintain weight, may serve as a ''buffer'' against the symptoms that eventually lead to fibromyalgia.
The results are entirely plausible, said Dr. Patrick Wood, senior medical adviser for the National Fibromyalgia Association, who cares for many fibromyalgia patients.
But with the condition, there are often the chicken-egg questions, he added, such as whether the pain leads to the inactivity or weight gain or vice versa. "It's difficult with any level of assurance to know what's driving what," Wood said. There could be underlying factors driving both excess weight and pain sensitivity, he noted.
The inflammation that is associated with obesity may heighten pain sensitivity, Wood added.
More study is needed, Wood said. Until more is known, however, he would advise people who want to avoid the condition to maintain a healthy weight and exercise regularly. That's especially wise for those with a family history of fibromyalgia, he stressed, because he has found that it does tend to run in families.
For those already diagnosed with the condition, Wood said, "some data show if you exercise and keep your weight down you may have less pain."
To learn more about fibromyalgia, visit the National Fibromyalgia Association.
SOURCES: Patrick Wood, M.D., senior medical advisor, National Fibromyalgia Association, and family medicine physician, Renton, Wash.; May 2010, Arthritis Care & Research
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