Dipartimento di Meccanica, Politecnico di Milano, via Privata Giuseppe la Masa 1, 20156, Milano, Italy; Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano, Italy.
Dipartimento di Meccanica, Politecnico di Milano, via Privata Giuseppe la Masa 1, 20156, Milano, Italy; Université Sorbonne Paris Nord, Institut de Biomécanique Humaine Georges Charpak, IBHGC, UR 4494, F-93000, Bobigny, France; Arts et Métiers Institute of Technology, F-75013, Paris, France; Département STAPS, Université Sorbonne Paris Nord, Bobigny, France.
Gait Posture. 2021 Sep;89:31-37. doi: 10.1016/j.gaitpost.2021.04.032. Epub 2021 Apr 23.
Vertical whole-body vibration (vWBV) during work, recreation, and transportation can have detrimental effects on physical and mental health. Studies have shown that lateral vibration at low frequencies (<3 Hz) can result in changes to spatiotemporal gait parameters. There are few studies which explore spatiotemporal gait changes due to vertical vibration at higher frequencies (> 3 Hz). This study seeks to assess the effect of vWBV on spatiotemporal gait parameters at a greater range of frequencies (≤ 30 Hz).
Stride Frequency (SF), Stride Length (SL), and Center of Pressure velocity (CoPv) was measured in seven male subjects (23 ± 4 years, 1.79 ± 0.05 m, 73.9 ± 9.7 kg) during In-Place Walking and nine male subjects (29 ± 7 years, 1.78 ± 0.07 m, 77.8 ± 9.9 kg; mean ± SD) during Treadmill Walking while exposed to vWBV. Load cells measured ground reaction forces during In-Place Walking and sensorized insoles acquired under-foot pressure during Treadmill Walking. Statistical tests included a one-way repeated-measures ANOVA, post-hoc two way paired T-tests, statistical power (1-β), correlation (R), and effect size (Cohen's d).
While statistical significance was not found for changes in SF, SL, or Mean CoPv, small to large effects were found in all measured spatiotemporal parameters of both setups. During Treadmill Walking, vWBV was correlated with a decrease in SF (R = 0.925), an increase in SL (R = 0.908), and an increase in Mean CoPv (R = 0.921) and Max CoPv (R = 0.952) with a significant increase (p < 0.0083) in Max CoPv at frequencies of 8 Hz and higher.
Study results demonstrated that vWBV influences spatiotemporal gait parameters at frequencies greater than previously studied.
工作、娱乐和交通中的垂直全身振动（vWBV）会对身心健康产生不利影响。研究表明，低频（<3 Hz）的横向振动会导致时空步态参数发生变化。很少有研究探讨由于高频（> 3 Hz）垂直振动导致的时空步态变化。本研究旨在评估 vWBV 在更大频率范围（≤ 30 Hz）下对时空步态参数的影响。
在原地行走时，对 7 名男性受试者（23 ± 4 岁，1.79 ± 0.05 m，73.9 ± 9.7 kg）和在跑步机行走时对 9 名男性受试者（29 ± 7 岁，1.78 ± 0.07 m，77.8 ± 9.9 kg；均值 ± 标准差）测量步频（SF）、步长（SL）和中心压力速度（CoPv）。在原地行走时，测力板测量地面反作用力，在跑步机行走时，传感器鞋垫采集足底压力。统计检验包括单向重复测量方差分析、事后双向配对 t 检验、统计功效（1-β）、相关性（R）和效应大小（Cohen's d）。
虽然在 SF、SL 或平均 CoPv 的变化方面未发现统计学意义，但在两种设置下的所有测量时空参数中都发现了小到中等的影响。在跑步机行走时，vWBV 与 SF 降低（R = 0.925）、SL 增加（R = 0.908）和平均 CoPv 增加（R = 0.921）和最大 CoPv 增加（R = 0.952）相关，最大 CoPv 在 8 Hz 及更高频率下显著增加（p < 0.0083）。
研究结果表明，vWBV 会影响高于先前研究的频率的时空步态参数。
