Whole-body vibration training increases muscle strength and mass in older women: a randomized-controlled trial

To determine whether 10 weeks of whole-body vibration (WBV) training has a significant effect on strength, muscle mass, muscle power, and mobility in older women, 26 subjects were randomly assigned to a WBV training group (n=13; mean age 79 years) and a control (CON) group (n=13; mean age 76 years). Maximal voluntary isometric contraction (MVIC) increased 38.8% in the WBV group, without changes in the CON group. Electromyographic activity of the vastus medialis (VM), the vastus lateralis, and the biceps femoris (BF) did not change in either group. Thigh muscle cross-sectional area increased significantly after training in VM (8.7%) and BF (15.5%). Muscle power at 20%, 40%, and 60% MVIC decreased from pre-test to post-test in the CON group; however, WBV training prevented the decrease in the WBV group. Consequently, mobility, measured by the Timed Up and Go test, increased significantly after training (9.0%) only in the WBV group. Ten weeks of lower limb WBV training in older women produces a significant increase in muscle strength induced by thigh muscle hypertrophy, with no change in muscle power. The adaptations to WBV found in the present study may be of use in counteracting the loss of muscle strength and mobility associated with age-induced sarcopenia.