A longitudinal study on the development of locomotion in infants

本研究的目的是通过持续观察婴儿从走路到跑步的过渡过程来研究运动的发展。研究对象是12名年龄在12到18个月之间的健康儿童。用两台VTR摄像机以60帧/秒的速度（DLT方法）记录下它们最大努力的运动。运动分析的运动学参数为平均速度、步长、步频、步宽。在从步行到跑步的过渡过程中，平均速度从1.61 m/s增加到1.80 m/s，步长、步长比和步频分别从40.6cm增加到43.0cm，从48.9%增加到51.5%，从4.14Hz增加到4.21Hz，但增幅不显著。此外，在本研究中，我们证实了在步行和跑步运动之间的过程中存在跳跃。跳跃运动的速度、步长、步长/身高比与跑步运动相似。跳步动作的频率高于步行和跑步动作的频率。最初的跳跃总是基于同一条腿的踢腿，并且在行走和跑步动作中，优势腿也表现出比对侧腿更高的速度、步长和步频。因此，即使在这么小的时候，这些婴儿也表现出了偏侧性。步宽、步宽/步长、步宽/身高均在跑步组高于步行组。婴儿期最初的行走和跳跃运动仍然不稳定。因此，在从步行到跑步的过渡中，支撑基础逐渐变小。我们认为这些运动的修正是运动稳定化发展的特征之一。我们推测，在婴儿中，跳跃动作是重复的，直到它稳定为跑步动作，我们认为跳跃动作是从走路到跑步动作转变过程中转移动作发展的一部分。少

The purpose of this study was to investigate the development of locomotion by continually observing the transitional process from the walking to the running motion in infants. The subjects were 12 healthy children aged from twelve to eighteen months. Their locomotion with maximal effort was videotaped using two VTR cameras operating at 60 fps(DLT method). Kinematic parameters to analyze locomotion were mean speed, step length, step frequency, step width. In the transitional process from walking to running, the mean speed increased from 1.61 m/s to 1.80 m/s, and step length, step length ratio, and step frequency also increased from 40.6cm to 43.0cm, from 48.9% to 51.5%, from 4.14Hz to 4.21Hz respectively, but the increase was not significant. In addition, in this study we confirmed that there was leaping in the process between the walking and the running motion. The speed, step length and step length/body height ratio of leaping was similar to that in the running motion. While, the step … More frequency of leaping was lower than that in both the walking and running motion. Initial leaping was always based on a kick from the same leg, and the dominant leg also showed higher speed, step length, and step frequency than the opposite leg in the walking and running motions. Thus, even at this very young age these infants showed laterality. The values for step width, step width/step length, and step width/body height were all higher in running than walking. Initial locomotions of walking and leaping in infancy are still unstable. Thus, the support basis becomes gradually smaller in the transition from walking to running. We considered that the modification of these movements are one of the features of the development of stabilization of the motion. We speculate that in infants the leaping motion is repeated until it stabilizes into the running motion and we consider the leaping motion to be part of the development of the transfer movement in the change from the walking to the running motion. Less