Whole-body vibration training improves balance control and sit-to-stand performance among middle-aged and older adults: a pilot randomized controlled trial

BACKGROUND: Aging is associated with decreased balance, which increases falling risk. The objective of the current study was to determine the feasibility and effects of whole-body vibration (WBV) training on knee extensor muscle power, limits of stability, and sit-to-stand performance among community-dwelling middle-aged and older adults in the United States. METHODS: A randomized pilot study with participant blinding was conducted. Feasibility outcomes included recruitment and compliance rate. Twenty-nine community-dwelling older adults were randomly assigned to perform body-weight exercises with either an individualized vibration frequency and amplitude, a fixed vibration frequency and amplitude, or no vibration. Isokinetic knee extensor power, limits of stability, and sit-to-stand tests were conducted before beginning the exercises (baseline) and after 8 weeks of training. RESULTS: With a favorable recruitment rate (58%) and compliance rates (attrition 9%; adherence 85%), the intervention was deemed feasible. The limits of stability endpoint excursion score for the individualized frequency–amplitude group was increased by 8.8 (12.9%; P = 0.025) after training, and that group’s maximum excursion score was increased by 9.2 (11.5%; P = 0.006) after training. The average weight transfer time score was significantly decreased by 0.2 s in the fixed group. The participants in the individualized group demonstrated a significant increase (3.2%) in weight rising index score after 8 weeks of WBV training. CONCLUSIONS: WBV training is feasible for use with elderly people, and this study achieved good recruitment and compliance. The present paper suggests that 8 weeks of WBV training improves limits of stability and sit-to-stand performance. Future studies must determine whether WBV training improves other factors that affect posture control. TRIAL REGISTRATION: This study was registered at the Texas Woman’s University Institutional Review Board [TWU IRB 17632] on the 3rd of November 2014.