Department of Biological Sciences, Graduate School of Science, The University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan.
Sci Rep. 2023 May 17;13(1):8000. doi: 10.1038/s41598-023-34910-5.
In human walking, whole-body angular momentum (WBAM) about the body centre-of-mass is reportedly maintained in a small range throughout a gait cycle by the intersegmental cancellation of angular momentum. However, the WBAM is certainly not zero, which indicates that external moments applied from the ground due to ground reaction forces (GRFs) and vertical free moments (VFMs) counteract the WBAM. This study provides a complete dataset of the WBAM, each segmental angular momentum, and the external moments due to GRFs and VFMs during human walking. This is done to test whether (1) the three components of the WBAM are cancelled by coordinated intersegmental movements, and whether (2) the external moments due to GRFs and VFMs contribute only minimally to WBAM regulation throughout a gait cycle. This study demonstrates that WBAM is regulated in a small range not only by the segment-to-segment cancellation, but also largely through contributions by the GRFs. The magnitude of VFM is significantly smaller than the peak vertical moment generated by the GRFs; however, in the single-support phase during walking, the VFM is possibly critical for coping with the change in the vertical WBAM due to force perturbations and arm or trunk movements.
在人类行走中，据报道，整个身体角动量（WBAM）围绕身体质心在步态周期内通过节段间角动量的抵消保持在小范围内。然而，WBAM 肯定不为零，这表明由于地面反作用力（GRFs）和垂直自由力矩（VFMs），从地面施加的外部力矩会抵消 WBAM。本研究提供了完整的 WBAM、每个节段角动量以及 GRFs 和 VFMs 产生的外部力矩的数据集，以测试以下两种情况：（1）WBAM 的三个分量是否通过协调的节段间运动抵消，以及（2）GRFs 和 VFMs 产生的外部力矩是否仅在步态周期内对 WBAM 调节的影响最小。本研究表明，WBAM 的调节范围不仅受到节段间抵消的影响，还受到 GRFs 的很大影响。VFMs 的幅度明显小于 GRFs 产生的最大垂直力矩；然而，在行走的单支撑阶段，VFMs 可能对于应对由于力干扰和手臂或躯干运动引起的垂直 WBAM 变化至关重要。
