Caryn Robert C, Dickey James P
School of Kinesiology, Western University, London, Ontario, Canada.
Dose Response. 2019 Feb 26;17(1):1559325819827467. doi: 10.1177/1559325819827467. eCollection 2019 Jan-Mar.
Many research studies have evaluated the effects of whole-body vibration exercise on muscular strength, standing balance, and bone density, but relatively few reports have evaluated safety issues for vibration exercises. Knee flexion reduces acceleration transmission to the head during static exercise. However, few studies have evaluated dynamic exercises. The purpose of this investigation was to evaluate the transmission of acceleration to the head during dynamic squats. Twelve participants performed dynamic squats (0°-40° of knee flexion) on a synchronous vertical whole-body vibration platform. Platform frequencies from 20 to 50 Hz were tested at a peak-to-peak nominal displacement setting of 1 mm. Transmissibilities from the platform to head varied depending on platform frequency and knee flexion angle. We observed amplification during 20 and 25 Hz platform vibration when knee flexion was <20°. Vibration from exercise platforms can be amplified as it is transmitted through the body to the head during dynamic squats. Similarly, this vibration energy contributes to observed injuries such as retinal detachment. It is recommended that knee flexion angles of at least 20° and vibration frequencies above 30 Hz are used when performing dynamic squat exercises with whole-body vibration.
许多研究评估了全身振动训练对肌肉力量、站立平衡和骨密度的影响，但评估振动训练安全性问题的报告相对较少。在静态训练期间，屈膝可减少加速度向头部的传递。然而，很少有研究评估动态训练。本研究的目的是评估动态深蹲时加速度向头部的传递。12名参与者在同步垂直全身振动平台上进行动态深蹲（屈膝0°至40°）。在峰峰值标称位移设置为1mm的情况下，测试了20至50Hz的平台频率。从平台到头部的传递率因平台频率和屈膝角度而异。当屈膝<20°时，我们观察到在20和25Hz平台振动期间出现放大现象。在动态深蹲期间，来自训练平台的振动在通过身体传递到头部时可能会被放大。同样，这种振动能量会导致如视网膜脱离等损伤。建议在进行全身振动动态深蹲训练时，使用至少20°的屈膝角度和高于30Hz的振动频率。
