Effectiveness of physical activity in reducing pain in patients with fibromyalgia: a blinded randomized clinical trial

The purpose of this study was to evaluate and compare the effectiveness of muscle-strengthening exercises (MS) and a walking program (WA) in reducing pain in patients with fibromyalgia. Ninety women, 30–55 years of age, diagnosed with fibromyalgia according to the American College of Rheumatology 1990 criteria, were randomized into 3 groups: WA Group, MS Group, and control group. Pain (visual analog scale) was evaluated as the primary outcome. Physical functioning (Fibromyalgia Impact Questionnaire, FIQ), health-related quality of life (Short-Form 36 Health Survey, SF-36), and use of medication were evaluated as secondary outcomes. Assessments were performed at baseline, 8, 16, and 28 weeks. Intention-to-treat and efficacy analyses were conducted. Sixty-eight patients completed the treatment protocol. All 3 groups showed improvement after the 16-week treatment compared to baseline. At the 28-week follow-up, pain reduction was similar for the WA and MS groups (P = 0.39), but different from the control group (P = 0.01). At the end of the treatment, 80% of subjects in the control group took pain medication, but only 46.7% in the WA and 41.4% in the MS groups. Mean FIQ total scores were lower for the WA and MS groups (P = 0.96) compared with the control group (P < 0.01). Patients in the WA and MS groups reported higher scores (better health status) than controls in almost all SF-36 subscales. MS was as effective as WA in reducing pain regarding all study variables; however, symptoms management during the follow-up period was more efficient in the WA group.