Department of Aerospace Biodynamics, School of Aerospace Medicine, Fourth Military Medical University, 710032, Xi'an, China.
Eur J Appl Physiol. 2012 Nov;112(11):3743-53. doi: 10.1007/s00421-012-2355-3. Epub 2012 Feb 28.
Skeletal unloading induced by disuse or immobilization causes a decrease in bone mass and strength. We investigated the relationship between whole-body vibration (WBV) and resistance exercise (RE) in preventing bone loss induced by 8-week hindlimb unloading in young male rats. Sixty male Wistar rats were assigned randomly to 6 groups: age-matched control group (CON, n = 10), hindlimb unloading group (HU, n = 10), hindlimb unloading + standing group (HU + ST, n = 10), hindlimb unloading + WBV group (HU + WBV, n = 10), hindlimb unloading + RE group (HU + RE, n = 10) and hindlimb unloading + WBV + RE group (HU + WBV + RE, n = 10). After 8-week hindlimb unloading, micro-CT scanning and three-point bending test were performed in the femur. Sera were collected for analysis of bone formation and resorption markers. Compared with HU group, WBV, RE and the combination of WBV and RE (WBV + RE) significantly improved (P < 0.01) one repetition maximum (1RM) (expressed as the percentage change from baseline, HU: -23%, HU + WBV: 21%, HU + RE: 48%, HU + WBV + RE: 51%), and maintained (P < 0.05) cancellous volumetric bone mineral density (vBMD) and trabecular structure. No difference of cortical vBMD was found among all groups (P > 0.05). WBV had no effects on biomechanical properties of the femur diaphysis (P > 0.05). RE and WBV + RE significantly increased maximum load and cross-sectional moment of inertia of the femur diaphysis in hindlimb unloading rats (P < 0.05). There was an interaction between WBV and RE in improving cancellous bone. These results demonstrate that WBV and RE interactively maintain cancellous structure and vBMD, and independently partially mitigate the reduction of bone strength in long-term hindlimb unloading rats.
废用或固定导致的骨骼卸载会导致骨量和骨强度下降。我们研究了全身振动（WBV）和抗阻运动（RE）在预防年轻雄性大鼠 8 周后肢去负荷引起的骨丢失中的关系。60 只雄性 Wistar 大鼠随机分为 6 组：年龄匹配的对照组（CON，n=10）、后肢去负荷组（HU，n=10）、后肢去负荷+站立组（HU+ST，n=10）、后肢去负荷+WBV 组（HU+WBV，n=10）、后肢去负荷+RE 组（HU+RE，n=10）和后肢去负荷+WBV+RE 组（HU+WBV+RE，n=10）。在后肢去负荷 8 周后，对股骨进行 micro-CT 扫描和三点弯曲试验。采集血清分析骨形成和吸收标志物。与 HU 组相比，WBV、RE 和 WBV 与 RE 的组合（WBV+RE）显著改善（P<0.01）最大重复次数（1RM）（表示为与基线相比的百分比变化，HU：-23%，HU+WBV：21%，HU+RE：48%，HU+WBV+RE：51%），并维持（P<0.05）松质骨体积骨密度（vBMD）和小梁结构。各组皮质 vBMD 无差异（P>0.05）。WBV 对股骨骨干的生物力学性能没有影响（P>0.05）。RE 和 WBV+RE 显著增加了后肢去负荷大鼠股骨骨干的最大负荷和横断截面惯性矩（P<0.05）。WBV 和 RE 在改善松质骨方面存在相互作用。这些结果表明，WBV 和 RE 相互作用维持松质结构和 vBMD，并独立部分减轻长期后肢去负荷大鼠骨强度的降低。
