Eight Weeks of Local Vibration Training Do Not Increase Tibialis Anterior Muscle Stiffness Evaluated by Supersonic Shear Imaging

Background

Local vibration (LV) training is efficient to improve muscle strength due to adaptations within the central nervous system. However, little is known about adaptations at the muscular level after this form of training. The aim of this study was to assess the effect of LV training on muscle elastic properties using supersonic shear imaging technique.

Methods

Twenty-eight subjects were allocated to a training (VIB, $n=14$) or control (CON, $n=14$) group. The VIB group performed twenty-four 1-h sessions (3 sessions/wk) of 100-Hz vibration applied to the tibialis anterior. Maximal force (MVC) as well as active and passive muscle stiffness (i.e. using elastography) were assessed before and after the LV training.

Results

MVC was increased by 9.4 ± 9.7% in VIB ($p<0.001$) while no changes were reported in CON ($p=0.52$). No changes were reported in passive and active muscle stiffness for both groups ($p>0.05$).

Conclusion

Our results suggest that adaptations in elastic muscle properties do not explain the increased muscle strength reported after LV training.