Acute Effects of Whole-Body Vibration on Lower Body Flexibility and Strength

Abstract

2380 Whole-body vibration (WBV) is a neuromuscular training method designed to improve muscle strength and mobility that has become an increasing popular mode of alternative training in European athletes. However, the extent of clinical research into the acute effects of whole-body vibration is limited. PURPOSE: The purpose of this study was to examine the acute effects of WBV training on flexibility, heart rate, skin temperature and peak isokinetic force. METHODS: Nine adults (5 males, 4 females), untrained to WBV, participated in the study. All participants stood upright on a vibration platform for a total of 6 minutes. Vibration frequency was gradually increased during the first minute to a frequency of 26 Hz, which was maintained for the remaining five minutes. Immediately prior to and following the 6 min of WBV, the subjects participated in assessments of heart rate, anterior thigh skin temperature, lower extremity flexibility and isokinetic strength. Heart rate and skin temperature were measured using portable heart rate monitors and a non-contact infrared thermometer. Lower extremity flexibility was determined using a sit-and-reach box test. Peak isokinetic force of knee extension and flexion were measured by means of a motor driven dynamometer with velocity fixed at 120 degrees/sec. Pre- and post comparisons were made using Students paired t-tests. RESULTS: Analyses revealed significant increases in flexibility (27.1 ± 12.1 vs. 32.8 ± 9.6 cm, p<0.05) and in heart rate response (81.1 ± 9.4 vs. 96.6 ± 7.8 bpm, p<0.05) following WBV. Peak isokinetic force of knee flexion increased significantly (101.6 ± 39.1 vs. 109.8 ± 40.2 Nm, p<0.05) as did peak knee extension (178.9 ± 53.9 vs. 190.7 ± 52.0 Nm, p<0.05). There was not a significant change in body temperature following WBV. CONCLUSION: The findings of this preliminary study suggests that WBV training may elicit acute improvements in flexibility, heart rate, and peak isokinetic force.