Abstract
Background
Fibromyalgia (FM) 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 FM.
Search methods
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 that were selected focused on cardiorespiratory endurance, muscle strength and/or flexibility as treatment for FM.
Data collection and analysis
Two of four reviewers independently extracted data for each study. All discrepancies were rechecked and consensus was 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 FM signs and symptoms, and physical function in individuals with FM 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 0.49, 95% CI: 0.23 to 0.75) and physical function (SMD 0.66, 95% CI: 0.41 to 0.92) and possibly on pain (SMD 0.65, 95% CI: -0.09 to 1.39) and tender points (SMD 0.23, 95% CI: -0.18 to 0.65). 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 FM symptoms. Strength training may also have benefits on some FM symptoms. Further studies on muscle strengthening and flexibility are needed. Research on the long-term benefit of exercise for FM is needed.
Plain language summary
Exercise for fibromyalgia
This summary of a Cochrane review presents what we know from research about the effect of exercise for fibromyalgia. The review shows that in people with fibromyalgia:
– moderate intensity aerobic training for 12 weeks may improve overall well-being and physical function; moderate intensity aerobic exercise probably leads to little or no difference in pain or tender points.
– strength training for 12 weeks may result in large reductions in pain, tender points and depression, and large improvement in overall well-being but may not lead to any difference in physical function.
– the exercise programs that were studied were safe for most. The intensity of aerobic exercise training should be increased slowly aiming for a moderate level. If exercisers experience increased symptoms, they should cut back until symptoms improve. If in doubt about adverse effects, they should check with a health care professional.
– it is not known whether exercise training for more than 12 weeks improves other symptoms such as fatigue, stiffness or poor sleep. Many people with FM do have difficulty staying on an exercise program. Strategies to help individuals exercise regularly were not measured in these studies.
– it is not known whether flexibility training, programs combining types of exercise, and programs combining exercise with non-exercise strategies improve the symptoms of fibromyalgia.
What is fibromyalgia and what are the different types of exercise?
Fibromyalgia is a syndrome of persistent widespread pain and tenderness. Individuals may also experience a wide range of other symptoms such as difficulty sleeping, fatigue, stiffness, and depression. Symptoms may put people off exercising but studies show that the majority are able to exercise. Exercise training can include aerobics such as stepping and walking; strengthening exercises such as lifting weights or using resistance machines; and stretching for flexibility. Although exercise is part of the overall management of fibromyalgia, this review examined the effects of exercise when used separately or combined with other strategies such as education programs, biofeedback and medications.
Best estimate of what happens to people with fibromyalgia who take part in aerobic exercise:
In the studies, aerobic exercises were done for at least 20 minutes once a day (or twice for at least 10 minutes), 2 to 3 days a week. Strength training was done 2 to 3 times a week and with at least 8 to 12 repetitions per exercise. The exercise programs lasted between 2 ½ to 24 weeks.
When compared to no exercising, aerobic exercise training may:
– improve overall well-being by 7 points on a scale of 0 to 100.
– improve ability to perform aerobic exercise; by using 2.8 ml/kg/minute more oxygen when walking on a treadmill.
– increase the amount of pressure that can be applied to a tender point by 0.23 kgs/cm2 before the onset of pain.
– reduce pain by 1.3 on a scale of 0 to 10.
– have unknown effects on fatigue, depression or stiffness.
These results are based on moderate quality evidence.
Best estimate of what happens to people with fibromyalgia who take part in strength training:
When compared to no exercise, strength training may:
– reduce pain by 49 fewer points on scale of 0 to 100.
– improve overall well-being by 41 points on a scale of 0 to 100.
– lead to 2 fewer active tender points on a scale of 0-18.
These results are based on low quality evidence.
The numbers given are our best estimate. When possible, we have also presented a range because there is a 95 percent chance that the true effect of the treatment lies somewhere within that range.
