Department of Kinesiology and Health, Georgia State University, Atlanta, GA, USA.
Department of Kinesiology and Health, Georgia State University, Atlanta, GA, USA.
Gait Posture. 2022 May;94:79-84. doi: 10.1016/j.gaitpost.2022.02.027. Epub 2022 Feb 25.
Anteriorly-loaded walking is common in many occupations and may increase fall risk. Dynamic gait stability, defined by the Feasible Stability Region (FSR) theory, quantifies the kinematic relationship between the body's center of mass (COM) and base of support (BOS). FSR-based dynamic gait stability has been used to evaluate the fall risk.
How does front load carriage affect dynamic gait stability, step length, and trunk angle among young adults during treadmill walking?
In this between-subject design study, 30 healthy young adults were evenly randomized into three load groups (0%, 10%, or 20% of body weight). Participants carried their assigned load while walking on a treadmill at a speed of 1.2 m/s. Body kinematics were collected during treadmill walking. Dynamic gait stability (the primary variable) was calculated for two gait events: touchdown and liftoff. Step length and trunk angle were measured as secondary variables. One-way analysis of variance was conducted to detect any group-related differences for all variables. Post-hoc analysis with Bonferroni correction was performed when main group differences were found.
No significant differences but medium to large effect sizes were found between groups for dynamic gait stability at touchdown (p = 0.194, η = 0.114) and liftoff (p = 0.122, η = 0.139). Trunk angle significantly increased (indicating backward lean) with the front load at touchdown (p < 0.001, η = 0.648) and liftoff (p < 0.001, η = 0.543). No significant between-group difference was found related to the step length (p = 0.344, η = 0.076).
Carrying a front load during walking significantly alters the trunk orientation and may change the COM-BOS kinematic relationship and, therefore, fall risk. The findings could inform the design of future studies focusing on the impact of anterior load carriage on fall risk during different locomotion.
在许多职业中，前负荷行走很常见，可能会增加跌倒风险。动态步态稳定性由可行稳定区域（FSR）理论定义，该理论量化了身体质心（COM）和支撑基础（BOS）之间的运动关系。基于 FSR 的动态步态稳定性已用于评估跌倒风险。
在跑步机行走过程中，前负荷搬运如何影响年轻人的动态步态稳定性、步长和躯干角度？
在这项基于个体的设计研究中，30 名健康的年轻人被平均随机分配到三个负荷组（0%、10%或 20%的体重）。参与者在以 1.2 m/s 的速度在跑步机上行走时携带指定的负荷。在跑步机行走过程中收集身体运动学数据。动态步态稳定性（主要变量）是为两个步态事件计算的：触地和离地。步长和躯干角度作为次要变量进行测量。使用单因素方差分析检测所有变量的任何组间差异。当主要组间差异存在时，进行具有 Bonferroni 校正的事后分析。
在触地和离地时，各组之间的动态步态稳定性没有显著差异，但具有中等至较大的效应量（p=0.194，η=0.114；p=0.122，η=0.139）。在前负荷的作用下，触地和离地时躯干角度明显增加（表示向后倾斜）（p<0.001，η=0.648；p<0.001，η=0.543）。步长在组间无显著差异（p=0.344，η=0.076）。
在行走时携带前负荷会显著改变躯干的方向，并可能改变 COM-BOS 的运动关系，从而增加跌倒风险。这些发现可以为未来的研究提供信息，重点关注前负荷搬运对不同运动方式下跌倒风险的影响。
