Researchers found that regular aerobic exercise decreased activity in memory and pain control areas of the brain.
"The decreased brain activity ... suggests that the brain is working more efficiently," says study researcher Brian Walitt, MD, in a news release.
"We also see less brain activity in areas responsible for pain processing, which might be aiding that efficiency," says Walitt, the director of the Fibromyalgia Evaluation and Research Center at the Georgetown University Medical Center in Washington, D.C.
The findings may help explain why regular exercise decreases pain and tenderness and improves brain function in people with fibromyalgia.
Fibromyalgia affects more than 5 million Americans, mainly women. Its most common symptoms include body-wide pain and tender points, fatigue, and difficulty sleeping. There can also be brain changes, such as memory and concentrations problems.
The study was presented at the Society of Neuroscience's annual meeting.
In this small study, researchers studied 18 women with fibromyalgia who had been taking medication for the condition. All the women received brain scans to measure their short-term memory. They also answered questions about their pain levels and overall well-being.
The women were asked to stop using their medication for six weeks. After that they had a second brain scan and took another round of memory tests. In the last stage of the study, the women exercised three times a week with a personal trainer.
During their half-hour workouts, the women could choose from several different kinds of aerobic activity. These included walking, cycling, swimming, and using a treadmill or an arm bicycle.
After participating in the fitness program for six weeks, the women received a final brain scan, memory testing, and a self-evaluation of their symptoms.
Initially, the women had more pain and memory problems when they stopped their medication. But after following a fitness program, memory returned to the levels seen at the start of the study. They also felt better physically and mentally, and they had less pain.