Effect of a whole-body vibration session on knee stability
The aim of the study was to investigate the effect of WBV on stretch reflexes involved in knee joint control. We evoked stretch reflexes of the hamstring muscles by inducing an anterior tibial translation during standing in 23 healthy subjects which were divided into a control and an intervention group. WBV with a frequency of 30Hz and a vertical amplitude of 4mmwas induced by an uniformly oscillating platform. The WBV session lasted 60 seconds and was repeated twice. Short (SLR) and medium latency responses (MLR) of the hamstring muscles and maximum tibia translation were assessed using surface EMG and linear potentiometers. While there were no significant changes in latency, the size of the lateral and medial hamstring SLR was significantly increased after WBV (p=0.039 and p=0.043, respectively). Nosignificant differences were found for the hamstring MLR size after WBV. Maximum tibial translation was significantly decreased after WBV (p=0.031). Our results suggest thatsingleWBVexposure hasa positive effect on knee joint stability as a short-term adaptation on neuromuscular level. This appears to be directlyassociated with an increase of hamstring SLR size in response to the anterior tibial movement which may cause the decrease in anterior tibial translation.Conclusion:
The results of this study suggest that a single session using the Power Plate® machine results in improved knee stability.
This is a summary of a study published in the:
International Journal of Sports Medicine. Vol. 29(10), pp: 839-844. 2008 Authors: M. Melnyk, B. Kofler, M. Faist, M. Hodapp, A. Gollhofer Affiliations: Department of Sport and Sports Science, University of Freiburg, Freiburg, Germany
Department of Neurology and Clinical Neurophysiology, University of Freiburg, Freiburg, Germany