Systematic review of physical exercise for patients with idiopathic inflammatory myopathies

Idiopathic inflammatory myopathies (IIM) are systemic autoimmune connective tissue diseases. The safety and effectiveness of exercise for patients with idiopathic inflammatory myopathies remains unclear. This study aimed to systematically review the evidence for physical exercise among patients with idiopathic inflammatory myopathies. Relevant experimental studies were identified through searching the PubMed, Cochrane, Embase, Scopus, and CINAHL databases, and studies involving any type of physical exercise for ≥1 month were considered. The primary outcome was muscle strength, and the secondary outcomes included aerobic fitness, functional performance, health status, quality of life, activities of daily living, pain, and fatigue. Eight randomized controlled trials and thirteen nonrandomized uncontrolled trials were reviewed. Physical exercise appeared safe, with several positive effects. However, selection or allocation biases and small sample sizes affected the certainty of the evidence. While physical exercise appeared safe for patients with idiopathic inflammatory myopathies with several positive effects, studies of a higher methodological quality and involving patients with active disease are needed. Furthermore, to design optimal exercise programs, consistent and sensitive outcome measures are needed to facilitate comparisons of results from different studies.