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Whole body vibration does not potentiate the stretch reflex
J T Hopkins1, D Fredericks, P W Guyon
1Human Performance Research Center, Brigham Young University, Provo, Utah, USA. tyhopkins@byu.edu
International Journal of Sports Medicine
|September 6, 2008
Summary
Whole body vibration (WBV) does not appear to enhance the quadriceps stretch reflex. A single session of WBV treatment did not alter reflex timing or amplitude in volunteers.
Area of Science:
- Neuromuscular Physiology
- Biomechanics
- Exercise Science
Background:
- Whole body vibration (WBV) is proposed to improve neural potentiation of the stretch reflex.
- Understanding WBV's effects on neuromuscular responses is crucial for optimizing training and rehabilitation.
Purpose of the Study:
- To investigate the acute effects of WBV on the quadriceps stretch reflex.
- To determine if WBV influences reflex latency, amplitude, electromechanical delay, or force output.
Main Methods:
- 22 healthy volunteers participated, with a matched control group.
- The quadriceps stretch reflex was measured before, immediately after, and 30 minutes post-WBV treatment.
- WBV involved 5 bouts of 1-minute at 26 Hz in a squatting position.
Main Results:
- No significant group-by-time interactions were found for reflex latency, EMG amplitude, electromechanical delay, or quadriceps force.
- Statistical analysis (Two-way ANOVAs) revealed no changes in any measured reflex parameters due to WBV.
Conclusions:
- A single session of whole body vibration does not acutely affect the quadriceps stretch reflex.
- The findings suggest WBV may not be effective for enhancing short-term neuromuscular potentiation of this specific reflex arc.
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