Research Institute MOVE, Faculty of Human Movement Sciences, VU University Van der Boechorststraat 9, NL-1081 BT, Amsterdam, The Netherlands.
J Exp Biol. 2010 Dec 1;213(Pt 23):3945-52. doi: 10.1242/jeb.045112.
Arm swing during human gait has been shown to reduce both angular momentum about the vertical and energy expenditure, and has been hypothesized to enhance gait stability. To examine this hypothesis, we studied the effect of arm swing on the local and global stability of steady-state gait, as well as the ability to perform adequate recovery actions following a perturbation. Trunk kinematics of 11 male subjects was measured in treadmill walking with normal and with restricted arm swing. In half of the trials, gait was perturbed by a position-controlled forward pull to the trunk. We constructed state spaces using data recorded from the unperturbed steady-state walking trials, and quantified local gait stability by calculating maximum Lyapunov exponents. In addition, we analyzed perturbation forces, the distance from the unperturbed gait pattern, and the return toward the normal gait pattern following an external perturbation. Walking without arm swing led to a non-significantly lower Lyapunov exponent (P=0.06), significantly higher perturbation forces (P<0.05), and significantly slower movements away from the attractor (P<0.01). These results suggest that gait without arm swing is characterized by similar local stability to gait with arm swing and a higher perturbation resistance. However, return towards the normal gait pattern was significantly slower (P<0.05) when walking with restricted arms, suggesting that the arms play an important role in the recovery from a perturbation. Collectively, the results suggest that arm swing as such does not enhance gait stability, but rather that recovery movements of the arms contribute to the overall stability of human gait.
人体行走时的摆臂运动已被证明可以减少垂直方向上的角动量和能量消耗，并被假设可以增强步态稳定性。为了检验这一假设，我们研究了摆臂对稳态步态的局部和整体稳定性的影响，以及在受到干扰后进行适当恢复动作的能力。在跑步机行走时，我们测量了 11 名男性受试者的躯干运动，并分别进行了正常摆臂和限制摆臂的实验。在一半的试验中，通过对躯干的位置控制前向拉动来干扰步态。我们使用未受干扰的稳态行走试验中记录的数据构建状态空间，并通过计算最大 Lyapunov 指数来量化局部步态稳定性。此外，我们还分析了干扰力、偏离未受干扰步态模式的距离以及在受到外部干扰后恢复到正常步态模式的情况。不摆臂行走会导致 Lyapunov 指数（P=0.06）略有降低、干扰力显著增加（P<0.05）以及远离吸引子的运动速度显著减慢（P<0.01）。这些结果表明，不摆臂行走的局部稳定性与摆臂行走相似，但抗干扰能力更高。然而，当手臂受到限制时，恢复到正常步态模式的速度明显较慢（P<0.05），这表明手臂在从干扰中恢复方面起着重要作用。总的来说，这些结果表明摆臂本身并不能增强步态稳定性，而是手臂的恢复运动有助于人体步态的整体稳定性。
