Liao Wang, Huang Quting, Ruan Guoqing, Zhou Jin
Business School, Sichuan University, Chengdu 610065, China.
National Engineering Laboratory for Clean Technology of Leather Manufacture, Sichuan University, Chengdu 610065, China; Department of Biomedical Engineering, Faculty of Engineering, The Hong Kong Polytechnic University, Hong Kong, China.
Foot (Edinb). 2023 Mar;54:101947. doi: 10.1016/j.foot.2022.101947. Epub 2022 Nov 3.
Preschoolers are within their critical time in motion development; while muscles are the fundamental units in motion control and by monitoring activated intensity and duration of muscles, preschooler's motor ability which would disclose their potential pathogenesis quality can be objectively and quantitatively assessed. Although a large number of studies were available on this issue, questions still being there: what are the patterns and characteristics of lower limb muscles when they are facing with the curve walking(CW) tasks; and then how individual muscle or muscle groups coordinated while turning curves. Our purpose of this study is first to portray the patterns and characteristics of lower limb muscles of healthy preschoolers while CW and then to insight their muscles' coordination mechanism and "neuro-musculo-skeletal" feedback during motion.
35 healthy preschoolers and 35 healthy adults' lower limbs surface electromyography (sEMG) were collected while left and right CW and four muscle groups (Tibialis Anterior, Lateral Gastrocnemius, Rectus Femoris, and Biceps Femoris) were recorded. sEMG variables such as Muscle Activation Time, Total Duration of Activity Time, Average Muscle Activation Rate and Average Rate of Change were calculated. Paired sample t-test was used to explore the differences of sEMG variables between preschoolers and adults when turning curves.
Preschoolers would adjust the gait by changing the activation time and activation rate to fulfill the curve turning tasks; but they also showed variations in coordination mechanism when contrasting with the adults group. Those findings in preschoolers would support to build muscles' coordination mechanism and further insight to neuro-muscular skeletal feedback regulation.
Although preschoolers performed good enough to switching gait from normal walking to CW, but gaps in their abilities were still apparent when compared to adults. Hence, with the help of highly recognizable muscle coordination mechanism in CW, motor dysfunction in lower limbs of preschool children can be effectively identified.
学龄前儿童正处于运动发育的关键时期；肌肉是运动控制的基本单位，通过监测肌肉的激活强度和持续时间，可以客观、定量地评估学龄前儿童的运动能力，这有助于揭示其潜在的发病机制。尽管关于这个问题已经有大量的研究，但仍存在一些问题：下肢肌肉在面对曲线行走（CW）任务时的模式和特征是什么；以及在转弯时单个肌肉或肌肉群是如何协调的。本研究的目的首先是描绘健康学龄前儿童在曲线行走时下肢肌肉的模式和特征，然后深入了解他们在运动过程中肌肉的协调机制和“神经 - 肌肉 - 骨骼”反馈。
收集35名健康学龄前儿童和35名健康成年人在左右曲线行走时的下肢表面肌电图（sEMG），并记录四个肌肉群（胫骨前肌、外侧腓肠肌、股直肌和股二头肌）。计算sEMG变量，如肌肉激活时间、活动总时长、平均肌肉激活率和平均变化率。采用配对样本t检验来探讨学龄前儿童和成年人在转弯时sEMG变量的差异。
学龄前儿童会通过改变激活时间和激活率来调整步态以完成转弯任务；但与成人组相比，他们在协调机制上也表现出差异。学龄前儿童的这些发现将有助于建立肌肉协调机制，并进一步深入了解神经肌肉骨骼反馈调节。
尽管学龄前儿童在从正常行走切换到曲线行走时表现良好，但与成年人相比，他们的能力差距仍然明显。因此，借助曲线行走中高度可识别的肌肉协调机制，可以有效识别学龄前儿童下肢的运动功能障碍。
