Effects of exercise training on fatigue in multiple sclerosis: A meta-analysis

OBJECTIVE: To provide a quantitative synthesis of randomized controlled trials examining the effect of exercise training on symptomatic fatigue in persons with multiple sclerosis (MS). METHODS: Electronic databases (Web of Science, PubMed, PsycInfo, and Google Scholar) were searched for articles published between 1960 and October 2012 by using the key words "fatigue," OR "tiredness," OR "energy," OR "mood," OR "lassitude," AND "exercise," OR "physical activity," OR "rehabilitation," OR "fitness" WITH "multiple sclerosis." The initial search resulted in 311 articles, of which 74 were reviewed in detail and 17 met the inclusion criteria and provided enough data to compute effect sizes (ESs; Cohen d). The meta-analysis was conducted using a meta-analysis software program, and a random-effects model was used to calculate the overall ES, expressed as Hedge g. RESULTS: The weighted mean ES from 17 randomized controlled trials with 568 participants with MS was 0.45 (standard error = 0.12, 95% confidence interval = 0.22-0.68, z = 3.88, p ≤ .001). The weighted mean ES was slightly heterogeneous (Q = 29.9, df = 16, p = .019). CONCLUSIONS: The cumulative evidence supports that exercise training is associated with a significant small reduction in fatigue among persons with MS.