Department of Physical Therapy, School of Physical Education, Physical Therapy and Occupational Therapy, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil.
Department of Physical Therapy, School of Physical Education, Physical Therapy and Occupational Therapy, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil.
J Biomech. 2021 Dec 2;129:110803. doi: 10.1016/j.jbiomech.2021.110803. Epub 2021 Oct 12.
Fast walking may require a non-uniform change of dynamic stiffness among lower limb joints to deal with this daily task's demands. The change of dynamic joint stiffness may be distinct between females and males. This study aimed to test for differences in dynamic stiffness among lower limb joints in response to increased walking speed in males and females. Thirty-five participants walked in two randomized conditions: self-selected speed and fast speed (25% greater than the self-selected speed). Dynamic stiffnesses of the ankle, knee, and hip were calculated as the linear slope of the moment-angle curve's regression line during their major power absorption phase of the walking cycle. The comparison between conditions showed that the knee (p < 0.001) and hip (p = 0.031) increased their stiffness at the fast compared to self-selected speed. Ankle stiffness was not different between conditions (p = 0.818). The comparison among joints across speeds showed that the knee had a greater increase than the ankle (p = 0.001) and hip (p < 0.001), with no difference between ankle and hip (p = 0.081). The sex of the participant influenced only the ankle stiffness, in which males had greater stiffness than females (p = 0.008). These findings demonstrated that the lower limb joints changed their dynamic stiffness differently, and only the ankle stiffness was influenced by sex. The non-uniform adjustments of stiffness may provide the necessary stability and allow the individual to deal with greater demand for walking fast.
快走可能需要下肢关节的非均匀动态刚度变化来应对这一日常任务的需求。女性和男性之间的动态关节刚度变化可能存在差异。本研究旨在测试男性和女性在增加行走速度时下肢关节动态刚度的差异。35 名参与者在两种随机条件下行走：自主选择速度和快速速度（比自主选择速度快 25%）。在行走周期的主要功率吸收阶段，通过对关节力矩-角度曲线回归线的线性斜率计算踝关节、膝关节和髋关节的动态刚度。条件比较显示，与自主选择速度相比，快速行走时膝关节（p<0.001）和髋关节（p=0.031）的刚度增加。踝关节的刚度在两种条件下没有差异（p=0.818）。在不同速度下比较关节发现，膝关节的增加幅度大于踝关节（p=0.001）和髋关节（p<0.001），但踝关节和髋关节之间没有差异（p=0.081）。参与者的性别仅影响踝关节的刚度，男性的刚度大于女性（p=0.008）。这些发现表明，下肢关节的动态刚度发生了不同的变化，只有踝关节的刚度受到性别影响。刚度的非均匀调整可能提供必要的稳定性，使个体能够应对快走的更大需求。
