Lower limb muscles actively contribute to maintain body posture but also act to attenuate soft tissues oscillations that occur during everyday life. This elicited activity can be exploited as a mean of neuromuscular training or rehabilitation. In this study, Whole Body Vibrations (WBV) at different frequencies were delivered to healthy subjects while holding static postures to test the transient muscles mechanical responses. Twenty-five participants underwent WBV at 15, 20, 25 and 30 Hz while holding either a static ‘hack squat’ or ‘fore feet’ posture. Soft tissue accelerations and surface electromyography (sEMG) were recorded from Gastrocnemius Lateralis (GL), Soleus (SOL) and Tibialis Anterior (TA) muscles. Estimated displacement at muscle bellies revealed a resonant pattern, different across frequencies and postures (p<.001). Specifically, a peak in the displacement was measured after the onset of the stimulation, followed by a drop and a further plateau (only after few seconds after the peak) suggesting a delayed neuromuscular activation. Although oscillation dampening was correlated to an increased muscular activity, only specific WBV settings were promoting a significant muscle contraction. For example, SOL and GL induced activation was maximal for subject in forefeet and while exposed to higher frequencies (p<.05). The non-immediate response of leg muscles to a vibratory stimulation confirms the tonic nature of the vibration induced muscle contraction (the tonic vibration reflex) and its strong influence on postural tonic muscles (GL and SOL). This may have significant impact on training or rehabilitation protocols aiming towards postural and balance improvement or recovery.