Differential Effects of Whole-Body Vibration and Floor Exercises on Muscle Architecture, Functional Performance, and Well-Being in Pre-Frail Seniors: A Randomized Controlled Trial

ABSTRACT Objective To compare the effects of a 6-week whole-body vibration (WBV) program versus floor exercises on physical and psychosocial outcomes in pre-frail elderly. Design In this randomized, single-blind, parallel-group superiority trial, 58 pre-frail participants aged ≥65 were randomized 1:1 to WBV or floor groups. Both groups performed structurally similar exercise programs (5 sessions/week), tailored to either a vibration platform or the floor. Primary outcomes were quadriceps thickness, Sonographic Thigh Adjustment Ratio (STAR), and Chair Stand Test (CST). Secondary outcomes included handgrip strength, body composition, performance, mobility, balance, and questionnaires on physical activity, mood, kinesiophobia, depression, quality of life, sleep, and fatigue. Assessments occurred at baseline and week 6, except for quadriceps thickness and STAR, also measured at weeks 2 and 4. Results While both interventions significantly improved quadriceps thickness, STAR, CST, performance, balance, mood, fatigue, and sleep quality, WBV showed greater STAR gains at week 6 (right: p = 0.027, left: p = 0.043) and better outcomes in Timed Get-Up-and-Go ( p = 0.008), depressive symptoms ( p = 0.036), fatigue ( p = 0.036), and trunk fat percentage ( p = 0.008) and mass ( p = 0.006), with no serious adverse events. Conclusion WBV yielded greater benefits in sarcopenia prevention, mobility, mood, fatigue, and body composition, though other outcomes showed no between-group differences, suggesting domain-specific rather than universal effects.