The effect of 6 months of whole body vibration training on strength in postmenopausal women

The purpose of this study was to investigate the effect of whole body vibration (WBV) training in postmenopausal women on strength. One hundred and ten postmenopausal women (age 61.5 plus or minus 6.3 years, mass 69.1 plus or minus 11.0 kg, height 1.67 plus or minus .05 m) participated in this study. Isometric strength and dynamic strength of the knee extensors and flexors was tested as peak force before, after 3 months and after 6 months of WBV training. After the pre-test, two groups trained WBV training. The first group (n = 31) trained on a vibration platform that only conducted horizontal vibrations (WBV grouphor), while the second group (n = 67) trained on a reciprocative vibration (WBV grouprec). The third group was a control group (n = 12) that did not train WBV. Each training group trained 3 times per week, eight times one minute squatting per session on their respective platform. Both training groups increased their peak force significantly in knee flexion (9.6%) and extension (9.2%) and in the isometric strength (15.7%) of the knee extensors while the control group had no significant increase in strength after the training period. In the WBV grouphor the increase was mostly shown in the first three months, while the isometric strength still significantly increased from month three to six (4.3%) in the WBV grouprec. It was concluded that both types of WBV training can help menopausal women with increasing their leg strength.