Purpose: The aim of this study was to investigate the effects of different whole-body vibration (WBV) frequencies on oxygenation of vastus lateralis (VL) and gastrocnemius medialis (GM) muscles during static squatting in sedentary and physically active healthy males.
Methods: Twenty volunteers (age: 24.6 ± 2.9 yr; body mass: 80.6 ± 11.8 kg; height: 178.1 ± 7.6 cm) participated in this study. Ten subjects were sedentary individuals and 10 were athletes practicing different sports. All subjects completed four trials (control, and 30-, 40-, and 50-Hz WBV) in a randomized controlled crossover design. The trials consisted of static squatting on a vibrating platform for a total duration of 110 s. Muscle-oxygenation status was recorded with near-infrared spectroscopy.
Results: The data analysis revealed no significant treatment-by-time interactions in tissue-oxygenation index (TOI) or Δ total hemoglobin volume (tHb) in VL and GM muscles. A significant main effect of time in TOI of both VL and GM muscles was identified (P < 0.001). VL TOI significantly decreased by 2.8% at 90 s in the control condition and by 3.3% at 110 s in the 30-Hz condition; VL TOI significantly increased by 2.1 and 3.0% at 30 s in the 40- and 50-Hz conditions, respectively. GM TOI significantly decreased by 3.2% at 60 s, by 4.1% at 90 s, and by 4.3% at 110 s in the control condition, and by 5.5% at 110 s in the 30-Hz condition.
Conclusion: This study showed that WBV exercise with frequencies of 30, 40, and 50 Hz and small amplitudes does not affect muscle oxygenation of VL and GM muscles to a higher degree than a nonvibration condition.
1Olympic Medical Institute, Northwick Park Hospital, Harrow, UNITED KINGDOM; 2University of Aberdeen, College of Life Sciences and Medicine, Aberdeen, UNITED KINGDOM; and 3University of L'Aquila, Department of Sciences and Biomedical Technologies, L'Aquila, ITALY
Address for correspondence: Marco Cardinale, Ph.D., Olympic Medical Institute, Northwick Park Hospital, Watford Rd HA1 3UJ, Harrow, UK; E-mail: Marco.Cardinale@boa.org.uk.
Submitted for publication August 2006.
Accepted for publication November 2006.