Effects of Vibrations on Gastrocnemius Medialis Tissue Oxygenation

Med Sci Sports Exerc. 2010 Aug 2. Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Canada 2Experimental Imaging Centre and Dept of Radiology, University of Calgary, Calgary, Canada.

Whole body vibrations (WBV) are known to affect muscle activity and tissue oxygenation but some energetic aspects are still poorly understood. This study investigates the effects of WBV on gastrocnemius muscle oxygen utilization rate and tissue oxygenation dynamics during exercise. METHODS:: The effects of vibration on gastrocnemius medialis muscle oxygenation was investigated during a dynamic exercise on a sample of 16 active male subjects (age 26.3 +/- 5.1 yr; mass 71.2 +/- 4.8 kg, mean +/- S.D). Both arterially occluded (AO) and nonoccluded (N/O) conditions were investigated. Tissue oxygenation was monitored with a near infra-red spectrometer (NIRS). Oxygen utilization rate and tissue oxygenation recovery were computed as the slopes of the regression line of the oxygenation decay and recovery respectively. A Fast Fourier Transform (FFT) was employed to determine the frequency spectrum of the oxygen saturation data. Electromyographic (EMG) activity was monitored using bipolar EMG electrodes. A windowed root mean square (RMS) analysis was used to monitor the amplitude of the EMG signal. RESULTS:: A statistically significant increase of 15% (p<0.05) in oxygen utilization rate was found for the vibration condition in the AO leg but not in the N/O leg. The oxygenation recovery rate for the vibration condition was 34% higher (p<0.05) than the control condition. A low frequency periodic oscillation (T asymptotically equal to10s) in the tissue oxygenation data was determined from the FFT spectrum. A statistically significant decrease in the oscillation frequency was noticed for the vibration condition compared to the control. CONCLUSION:: Vibrations increased the oxygen utilization rate during a dynamic exercise. The oxygenation recovery rate increased with vibrations. The low frequency oscillation of the oxygenation was attributed to periodic changes in tissue blood flow and appears to be influenced by vibrations.

*taken from pubmed.org