The central nervous system (CNS) achieves a stable gait at several speeds and modes while controlling diverse instability. An essential feature of a gait is the motion of the center of body mass (CoM). CoM motion is at larger risk for trespassing the base of support in the mediolateral direction than in the anteroposterior direction. How the CoM trajectory in the frontal plane changes depending on the speed or mode can thus provide insights about the neural control of stable gaits. Here, we reveal the speed- and mode-dependent modulations of the trajectory by utilizing a Lissajous curve. The current study clarifies that speed-dependent modulations are evident in walking. Between walking and running, there were significant mode-dependent modulations. In contrast, there were no significant speed-dependent modulations during running. Deviations from standard tendencies quantified via Lissajous curve fitting could be a sign of gait impairments and recovery after treatments.

中枢神经系统（CNS）在多种速度和模式下均能保持稳定的步态，同时还能控制各种不稳定性。步态的基本特征是体重中心（CoM）的运动。与在前后方向相比，CoM运动在中外侧方向上侵入支撑基座的风险更大。因此，额叶平面上的CoM轨迹如何根据速度或模式而变化可以提供有关稳定步态的神经控制的见识。在这里，我们通过利用李沙育曲线揭示了轨迹的速度和模式相关调制。当前的研究澄清了在步行中速度依赖的调制是明显的。在步行和跑步之间，存在与模式有关的重要调制。相反，在跑步过程中没有明显的速度相关调制。