Exercise, fibromyalgia, and fibrofog: a pilot study.

BACKGROUND This pilot study was designed to test the efficacy of a physical activity program for improving psychological variables and fibromyalgia syndrome (FMS) symptoms and to provide preliminary evidence regarding the effects on perceived cognitive symptoms and objectively measured cognitive performance by FMS patients. METHODS Sixteen women diagnosed with FMS were randomly assigned to an 18-week physical activity program or to a control condition. Psychological measures, FMS symptoms, perceived cognitive function, objective measures of cognition, and walking capacity were assessed at baseline and posttest. RESULTS At posttest, there were significant differences in fatigue (effect size, ES=1.86), depression (ES=1.27), FMS symptoms (ES=1.56), self-reported cognitive symptoms (ES=1.19), and delayed recall performance (ES=1.16) between the physically active group and the control group, indicating that the FMS patients benefited from physical activity. Beneficial effects were also observed for 6 of the 7 objective measures of cognition and ranged from small to large (ESs=0.26 to 1.06). CONCLUSIONS Given that all FMS patients do not respond well to conventional treatments, these beneficial effects of physical activity are important. Future studies with larger samples are warranted to test the reliability of the findings for the objective measures of cognition.