Render Anna C, Cusumano Joseph P, Dingwell Jonathan B
Department of Kinesiology, The Pennsylvania State University, University Park, PA 16802, USA.
Department of Engineering Science & Mechanics, The Pennsylvania State University, University Park, PA 16802, USA.
J Biomech. 2025 Feb;180:112495. doi: 10.1016/j.jbiomech.2025.112495. Epub 2025 Jan 7.
Most often, gait biomechanics is studied during straight-ahead walking. However, real-life walking imposes various lateral maneuvers people must navigate. Such maneuvers challenge people's lateral balance and can induce falls. Determining how people regulate their stepping movements during such complex walking tasks is therefore essential. Here, 24 adults (12F/12M; Age 25.8±3.5yrs) walked on wide or narrow virtual paths that were either straight, slowly-winding, or quickly-winding. From each trial, we computed time series of participants' step widths and their lateral body positions relative to their path. We applied our Goal Equivalent Manifold framework - an analysis of how task-level redundancy impacts motor regulation - to quantify how participants adjusted their step width and lateral position from step to step as they walked on these paths. On the narrower paths, participants walked with narrower steps and less lateral position and step width variability. They did so by correcting step-to-step deviations in lateral position more, while correcting step-to-step deviations in step width less. On the winding paths, participants took both narrower and more variable steps. Interestingly, on slowly-winding paths, participants corrected step-to-step deviations in step width more by correcting step-to-step deviations in lateral position less: i.e., they prioritized maintaining step width over position. Conversely, on quickly-winding paths, participants strongly corrected step-to-step deviations in both step width and lateral position: i.e., they prioritized maintaining both approximately equally, consistent with trying to maximize their maneuverability. These findings have important implications for persons who have elevated fall risk.
大多数情况下，步态生物力学是在直线行走过程中进行研究的。然而，现实生活中的行走需要人们进行各种横向动作。这些动作对人们的横向平衡构成挑战，并可能导致跌倒。因此，确定人们在这种复杂的行走任务中如何调节其步行动作至关重要。在此，24名成年人（12名女性/12名男性；年龄25.8±3.5岁）在宽阔或狭窄的虚拟路径上行走，这些路径要么是直的，要么是缓慢弯曲的，要么是快速弯曲的。从每次试验中，我们计算了参与者步幅宽度以及他们相对于路径的身体横向位置的时间序列。我们应用了我们的目标等效流形框架——一种关于任务级冗余如何影响运动调节的分析——来量化参与者在这些路径上行走时如何逐步步幅调整其步幅宽度和横向位置。在较窄的路径上，参与者行走时步幅更窄，横向位置和步幅宽度的变化更小。他们通过更多地纠正横向位置的逐步偏差，同时较少地纠正步幅宽度的逐步偏差来做到这一点。在弯曲的路径上，参与者的步幅既更窄又更具变化性。有趣的是，在缓慢弯曲的路径上，参与者通过较少地纠正横向位置的逐步偏差来更多地纠正步幅宽度的逐步偏差：也就是说，他们优先保持步幅宽度而不是位置。相反，在快速弯曲的路径上，参与者强烈纠正步幅宽度和横向位置的逐步偏差：也就是说，他们优先大致平等地保持两者，这与试图最大化其机动性一致。这些发现对跌倒风险较高的人具有重要意义。
