Meta-analytic and Scoping Study on Strength Training in People With Multiple Sclerosis

Manca, A, Dvir, Z, and Deriu, F. Meta-analytic and scoping study on strength training in people with multiple sclerosis. J Strength Cond Res 33(3): 874-889, 2019-Aim of the study was to determine a pooled estimate of effect on muscle strength and functional capacity induced by strength training in people with multiple sclerosis (PwMS). Five databases and 2 public registries were searched from inception to May 2017. Indexing terms used were: "multiple sclerosis," "resistance training," and "strength training." After title/abstract screening, 2 independent reviewers evaluated the studies' eligibility, which were retained if PwMS were randomly assigned to strength training or to a no intervention group. Of the 1,467 items retrieved, 30 randomized controlled trials formed the initial database with 11 trials (426 subjects) entering the final meta-analysis. The quality of the included studies was assessed by the PEDro scale and the risk of bias using the Cochrane Risk-of-Bias tool. All meta-analyses were conducted using a random effects model. After interventions, PwMS increased strength by 23.1% (confidence interval [CI] 11.8-34.4; +12.1 N; CI 4.5-19.8; p = 0.002; n = 366 subjects) at a small-to-moderate effect size (0.37; CI 0.2-0.6). Walking speed increased by 16.3 ± 10.7% (p = 0.0002; effect size 0.54; n = 275 subjects), distance covered in the 2-minute walking test by 6.7 ± 6.4% (p = 0.04; effect size 0.50; n = 111 subjects). People with MS respond to resistance training with consistent strength gains. Methodological inconsistencies among studies and inadequate reporting of the findings limited a comprehensive determination of the impact of strength improvements on patient functioning, except for walking performance which seemed significantly improved. Methodological steps and scoping lines are provided to establish a common platform for future trials.