Zaidell Lisa N, Pollock Ross D, James Darren C, Bowtell Joanna L, Newham Di J, Sumners David P, Mileva Katya N
Sport and Exercise Science Research Centre, London South Bank University, London, United Kingdom.
Centre of Human and Applied Physiological Sciences, King's College London, London, United Kingdom.
Dose Response. 2019 Jan 6;17(1):1559325818819946. doi: 10.1177/1559325818819946. eCollection 2019 Jan-Mar.
The aim of this study was to characterize acceleration transmission and neuromuscular responses to rotational vibration (RV) and vertical vibration (VV) at different frequencies and amplitudes.
Twelve healthy males completed 2 experimental trials (RV vs VV) during which vibration was delivered during either squatting (30°; RV vs VV) or standing (RV only) with 20, 25, and 30 Hz, at 1.5 and 3.0 mm peak-to-peak amplitude. Vibration-induced accelerations were assessed with triaxial accelerometers mounted on the platform and bony landmarks at ankle, knee, and lumbar spine.
At all frequency/amplitude combinations, accelerations at the ankle were greater during RV (all < .03) with the greatest difference observed at 30 Hz, 1.5 mm. Transmission of RV was also influenced by body posture (standing vs squatting, < .03). Irrespective of vibration type, vibration transmission to all skeletal sites was generally greater at higher amplitudes but not at higher frequencies, especially above the ankle joint. Acceleration at the lumbar spine increased with greater vibration amplitude but not frequency and was highest with RV during standing.
CONCLUSIONS/IMPLICATIONS: The transmission of vibration during whole-body vibration (WBV) is dependent on intensity and direction of vibration as well as body posture. For targeted mechanical loading at the lumbar spine, RV of higher amplitude and lower frequency vibration while standing is recommended. These results will assist with the prescription of WBV to achieve desired levels of mechanical loading at specific sites in the human body.
本研究旨在描述在不同频率和振幅下，旋转振动（RV）和垂直振动（VV）的加速度传递以及神经肌肉反应。
12名健康男性完成了2项实验（RV与VV），在深蹲（30°；RV与VV）或站立（仅RV）过程中，以20、25和30Hz的频率，1.5和3.0mm峰峰值振幅施加振动。使用安装在平台以及踝关节、膝关节和腰椎骨标志处的三轴加速度计评估振动诱发的加速度。
在所有频率/振幅组合下，RV期间踝关节处的加速度更大（均P < .03），在30Hz、1.5mm时差异最大。RV的传递也受身体姿势（站立与深蹲，P < .03）影响。无论振动类型如何，振动传递到所有骨骼部位通常在较高振幅时更大，但在较高频率时并非如此，尤其是在踝关节以上。腰椎处的加速度随振动振幅增大而增加，但不随频率增加，且站立时RV作用下最高。
结论/启示：全身振动（WBV）期间的振动传递取决于振动的强度和方向以及身体姿势。对于腰椎的靶向机械负荷，建议站立时采用较高振幅和较低频率的RV振动。这些结果将有助于制定WBV方案，以在人体特定部位实现所需的机械负荷水平。
