Systematically controlling for the influence of age, sex, hertz and time post-whole-body vibration exposure on four measures of physical performance in community-dwelling older adults: A randomized cross-over study

Abstract

Though popular, there is little agreement on what whole-body vibration (WBV) parameters will optimize performance. This study aimed to clarify the effects of age, sex, hertz and time on four physical function indicators in community-dwelling older adults (N = 32). Participants were exposed to 2min WBV per session at either 2Hz or 26Hz and outcome measures were recorded at 2, 20 and 40min post-WBV. Timed get up-and-go and chair sit-and-reach performances improved post-WBV for both sexes, were significantly different between 2Hz and 26Hz treatments (P ≤ 0.05) and showed statistically significant interactions between age and gender (P ≤ 0.01). Counter movement jump and timed one-legged stance performances showed a similar but non-significant response to 2Hz and 26Hz treatments, though male subjects showed a distinct trended response. Age and gender should be statistically controlled and both 2Hz and 26Hz exert a treatment effect. Copyright © 2011 Harold L. Merriman et al.