Alterations in the ability to maintain balance as a result of stochastic resonance whole body vibration in women

PurposeA vertical posture makes it difficult to maintain balance especially in the elderly. Loss of balance leads to falls and injuries. In the present study, we evaluated whether balance maintenance can be improved with the use of stochastic resonance whole body vibration (SR-WBV).MethodsAn examination of balance, involving 187 women aged 19–74 years, was conducted using double-plate posturography pre and post SR-WBV. The SR-WBV trainings were performed using the SRT Zeptor Medical-plus noise device. The entire study lasted 6 weeks, with a total of 12 training sessions, each consisting of nine 45 second series, with a 45 second pause between them.ResultsPost SR-WBV there was a reduction in the value of: the resultant mean velocity (MV) of the movement of COP (centre of pressure) for both lower limbs (B) and in the right lower limb (R) during the test with eyes closed (EC), the mean velocity and mean amplitude (MA) of the movement of COP along the x-axis (ML) of the left lower limb (L) during the test with eyes open (EO) and closed and some additional parameters. Negative correlations between age/index of improvement of MV-EC-B, MV-EC-L and MVML-EC-L, and BMI/index of improvement of MV-EC-B, MVML-EC-B appeared. Height correlated positively with the index of improvement of MV-EC-B and MVML-EC-B.ConclusionsAs a result of SR-WBV, the left leg is more stable along the x-axis and the disproportion between the stability of both legs is reduced. Consequently, body stability is higher. The SR-WBV is more effective in younger, taller and slimmer women. SR-WBV parameters should be optimized so that the training is more beneficial for elderly and shorter women, and for women with a higher BMI.

【研究目的】直立姿势尤其会使老年人难以维持身体平衡，而平衡丧失会引发跌倒与损伤。本研究旨在评估应用随机共振全身振动（stochastic resonance whole body vibration, SR-WBV）能否改善人体平衡维持能力。【研究方法】本研究纳入187名年龄介于19~74岁的女性受试者，采用双板姿势描记法（double-plate posturography）在SR-WBV训练前后开展平衡能力检测。SR-WBV训练使用SRT Zeptor Medical-plus噪声设备进行。整个研究周期为6周，共计12次训练课程；每次训练包含9组时长45秒的训练单元，组间设置45秒的休息间隔。【研究结果】SR-WBV训练后，多项平衡相关指标出现显著改善：闭眼（eyes closed, EC）测试中，双侧下肢（both lower limbs, B）及右侧下肢（right lower limb, R）的压力中心（centre of pressure, COP）运动合成平均速度（mean velocity, MV）均有所降低；睁眼（eyes open, EO）及闭眼测试中，左侧下肢（left lower limb, L）的压力中心沿X轴（即内外侧向轴ML）运动的平均速度与平均振幅（mean amplitude, MA）均出现下降，另有部分额外参数得到改善。此外，年龄与双侧下肢闭眼测试的压力中心运动合成平均速度（MV-EC-B）、左侧下肢闭眼测试X轴方向压力中心运动平均速度（MVML-EC-L）的改善指数呈负相关；身体质量指数（Body Mass Index, BMI）与双侧下肢闭眼测试的压力中心运动合成平均速度（MV-EC-B）、左侧下肢闭眼测试X轴方向压力中心运动平均速度（MVML-EC-B）的改善指数呈负相关；身高则与双侧下肢闭眼测试的压力中心运动合成平均速度（MV-EC-B）及X轴方向平均速度（MVML-EC-B）的改善指数呈正相关。【研究结论】SR-WBV训练可使左侧下肢沿X轴方向的稳定性得到提升，双侧下肢间的稳定性失衡状况得到改善，进而整体身体平衡稳定性得以增强。SR-WBV训练对更年轻、身高更高且体型更苗条的女性群体效果更为显著。未来需对SR-WBV的训练参数进行优化，以使该训练对老年、身材较矮以及身体质量指数较高的女性群体更为有益。