Effect of 6 months of whole body vibration on lumbar spine bone density in postmenopausal women: a randomized controlled trial

BACKGROUND: The issue of osteoporosis-induced fractures has attracted the world’s attention. Postmenopausal women are particularly at risk for this type of fracture. The nonmedicinal intervention for postmenopausal women is mainly exercise. Whole body vibration (WBV) is a simple and convenient exercise. There have been some studies investigating the effect of WBV on osteoporosis; however, the intervention models and results are different. This study mainly investigated the effect of high-frequency and high-magnitude WBV on the bone mineral density (BMD) of the lumbar spine in postmenopausal women. METHODS: This study randomized 28 postmenopausal women into either the WBV group or the control group for a 6-month trial. The WBV group received an intervention of high-frequency (30 Hz) and high-magnitude (3.2 g) WBV in a natural full-standing posture for 5 minutes, three times per week, at a sports center. Dual-energy X-ray absorptiometry was used to measure the lumbar BMD of the two groups before and after the intervention. RESULTS: Six months later, the BMD of the WBV group had significantly increased by 2.032% (P=0.047), while that of the control group had decreased by 0.046% (P=0.188). The comparison between the two groups showed that the BMD of the WBV group had increased significantly (P=0.016). CONCLUSION: This study found that 6 months of high-frequency and high-magnitude WBV yielded significant benefits to the BMD of the lumbar spine in postmenopausal women, and could therefore be provided as an alternative exercise.