Acute Effects of Whole-Body Vibration on Quadriceps Isometric Muscular Endurance in Middle-Aged Adults: A Pilot Study

This study analysed the acute effects of whole-body vibration (WBV) on quadriceps isometric muscular endurance. Fifteen healthy middle-aged males performed an endurance isometric strength test after three different warm-up conditions: static half squat plus WBV (HSV), static half squat without WBV (HS), and control condition (CC). The endurance isometric strength test consisted of 10 maximal isometric contractions held for 4 s and interspersed by 2 s of rest between each repetition. Rate of Perceived Exertion (RPE) was assessed after warm-up (RPE1) and at the end of the testing session (RPE2). During each testing session, participant's heart rate (HR) was continuously recorded. For each trial, the mean force across the 10 repetitions and fatigue index were evaluated. Mean force was significantly higher (p < 0.01) in CC than in the other two conditions. Both RPE1 and RPE2 were significantly lower (p < 0.01) in CC than HSV and HS condition. Warm-up HR and the mean testing session HR were significantly lower in CC than the other two conditions (p < 0.01). No significant differences were observed in fatigue index between conditions (p > 0.05) or in HR during the endurance protocol. Performing half-squat with or without vibration stimuli does not increase isometric muscular endurance and does not influence fatigue index.