Effects of 3 weeks’ whole body vibration training on muscle strength and functional mobility in hospitalized persons with multiple sclerosis

BACKGROUND: Exercise therapy in persons with multiple sclerosis (MS) is effective for improving muscle strength and functional mobility. OBJECTIVE: To investigate, in MS patients attending an in-patient rehabilitation program, the additional effects of a 3-week exercise program, performed on a whole body vibration platform, on muscle strength and functionality. METHODS: Median Expanded Disability Status Scale (EDSS) of participating patients was 5.5. This randomized controlled trial differentiated a MS control group (n = 17) and two exercise groups performing exercises on a vibration platform (WBV-full group, n = 20) and on the platform additionally covered by a damping mat (WBV-light group, n = 18). Exercise groups performed, during 10 training sessions, six static and dynamic exercises standing on a platform vibrating at high frequency and low amplitude. Isometric muscle strength of quadriceps, hamstrings, tibialis anterior and gluteus medius was measured with a hand-held dynamometer. Functional mobility was measured with Berg Balance Scale (BBS), 3-minute walk test and Timed Get up and Go test. RESULTS: Eight drop-outs occurred in the exercise groups (WBV-full = 4, WBV-light = 4), but were unrelated to WBV as type of intervention. Across groups, significant time effects were found for all muscle groups. For maximal quadriceps and hamstrings muscle strength, interaction effects were found with post-hoc tests indicating exercise group-significant improvements in the WBV-full group only. Significant time effects were found for all functional tests. Improvements on the BBS and 3-minute walk test were larger in training than in control groups, but no significant interactions were found. CONCLUSIONS: A 3-week exercise program on a vibration plate significantly improved muscle strength, but not functionality, in persons with MS.