Background: Fibromyalgia (FMS) is a syndrome expressed by chronic widespread body pain which leads to reduced physical function and frequent use of health care services. Exercise training is commonly recommended as a treatment. This is an update of a review published in Issue 2, 2002.
Objectives: The primary objective of this systematic review was to evaluate the effects of exercise training including cardiorespiratory (aerobic), muscle strengthening, and/or flexibility exercise on global well-being, selected signs and symptoms, and physical function in individuals with FMS.
Search strategy: We searched MEDLINE, EMBASE, CINAHL, SportDiscus, PubMed, PEDro, and the Cochrane Central Register for Controlled Trials (CENTRAL, Issue 3, 2005) up to and including July 2005. We also reviewed reference lists from reviews and meta-analyses of treatment studies.
Selection criteria: Randomized trials focused on cardiorespiratory endurance, muscle strength and/or flexibility as treatment for FMS were selected.
Data collection and analysis: Two of four reviewers independently extracted data for each study. All discrepancies were rechecked and consensus achieved by discussion. Methodological quality was assessed by two instruments: the van Tulder and the Jadad methodological quality criteria. We used the American College of Sport Medicine (ACSM) guidelines to evaluate whether interventions had provided a training stimulus that would effect changes in physical fitness. Due to significant clinical heterogeneity among the studies we were only able to meta-analyze six aerobic-only studies and two strength-only studies.
Main results: There were a total of 2276 subjects across the 34 included studies; 1264 subjects were assigned to exercise interventions. The 34 studies comprised 47 interventions that included exercise. Effects of several disparate interventions on global well-being, selected signs and symptoms, and physical function in individuals with FMS were summarized using standardized mean differences (SMD). There is moderate quality evidence that aerobic-only exercise training at recommended intensity levels has positive effects global well-being (SMD 0.44, 95% confidence interval (CI 0.13 to 0.75) and physical function (SMD 0.68, 95% CI 0.41 to 0.95) and possibly on pain (SMD 0.94, 95% CI -0.15 to 2.03) and tender points (SMD 0.26, 95% CI -0.28 to 0.79). Strength and flexibility remain under-evaluated.
Authors' conclusions: There is 'gold' level evidence (www.cochranemsk.org) that supervised aerobic exercise training has beneficial effects on physical capacity and FMS symptoms. Strength training may also have benefits on some FMS symptoms. Further studies on muscle strengthening and flexibility are needed. Research on the long-term benefit of exercise for FMS is needed.