A Systematic Review of the Effect of Physical Activity on Asthma Outcomes.

BACKGROUND:Asthma is a chronic respiratory disease that affects millions worldwide. Medication management is the current mainstay of treatment; however, there is evidence to suggest additional benefit with lifestyle changes, particularly with increased physical activity. OBJECTIVE:To discover and evaluate the effects of physical activity on asthma outcomes. METHODS:Systematic search of PubMed, Excerpta Medica database, Cumulative Index to Nursing and Allied Health Literature, Cochrane Library, Rehabilitation and Sports Medicine Source, Scopus, and Web of Science identified 11,155 results. Thirty-five articles met our inclusion criteria spanning 20 studies. Data extraction was conducted by 6 independent reviewers, and final results were evaluated by a seventh reviewer and the senior author. RESULTS:Wide variation among selected studies, including the heterogeneity of interventions and outcome variables, did not support a meta-analysis. Mixed results of the effects of physical activity on asthma outcomes were found. Most studies suggest that physical activity improves asthma control, quality of life, lung function parameters, and inflammatory serologies, whereas 3 found no improvements in any of these outcomes. No studies reported worsening asthma outcomes. CONCLUSIONS:This review highlights the emerging and promising role of physical activity as a nonpharmacologic treatment for asthma. Additional high-quality randomized controlled trials are needed to overcome the problems of measurement heterogeneity and the dilution of outcome effect size measurement related to physical activity interventions for asthma.