Harkness-Armstrong Carla, Hodson-Tole Emma F, Wood Greg, Mills Richard
Centre for Physical Activity in Health and Disease, Division of Sport, Health, and Exercise Sciences, Brunel University London, Uxbridge, United Kingdom.
Department of Life Sciences, Manchester Metropolitan University, Manchester, United Kingdom.
Front Hum Neurosci. 2023 Oct 27;17:1267424. doi: 10.3389/fnhum.2023.1267424. eCollection 2023.
The majority of children with developmental coordination disorder (DCD) struggle with static and dynamic balance, yet there is limited understanding of the underlying neuromechanical mechanisms that underpin poor balance control in these children. Eighteen children with DCD and seven typically developing (TD) children aged 7-10 years stood with eyes open on a moveable platform progressively translated antero-posteriorly through three frequencies (0.1, 0.25 and 0.5 Hz). Myoelectric activity of eight leg muscles, whole-body 3D kinematics and centre of pressure were recorded. At each frequency, postural data were divided into transition-state and steady-state cycles. Data were analyzed using a linear mixed model with follow-up Tukey's pairwise comparisons. At the slowest frequency, children with DCD behaved like age-matched TD controls. At the fastest frequency, children with DCD took a greater number of steps, had a greater centre of mass variability, had a greater centre of pressure area, and tended to activate their muscles earlier and for longer than TD children. Children with DCD did not alter their postural response following prolonged exposure to platform movement, however they made more, non-structured postural adjustments in the medio-lateral direction as task difficulty increased. At the faster oscillation frequencies, children with DCD adopted a different muscle recruitment strategy to TD children. Activating their muscles earlier and for longer may suggest that children with DCD attempt to predict and react to postural disturbances, however the resulting anticipatory muscle excitation patterns do not seem as finely tuned to the perturbation as those demonstrated by TD children. Future work should examine the impact of balance training interventions on the muscle recruitment strategies of children with DCD, to ensure optimal interventions can be prescribed.
大多数患有发育性协调障碍（DCD）的儿童在静态和动态平衡方面存在困难，但对于这些儿童平衡控制不佳背后的神经力学机制，人们的了解有限。18名患有DCD的儿童和7名7至10岁发育正常（TD）的儿童在一个可移动平台上睁眼站立，该平台以三种频率（0.1、0.25和0.5赫兹）前后逐渐平移。记录了八条腿部肌肉的肌电活动、全身三维运动学和压力中心。在每个频率下，姿势数据被分为过渡状态和稳态周期。使用线性混合模型并进行后续的Tukey成对比较来分析数据。在最慢的频率下，患有DCD的儿童表现得与年龄匹配的TD对照组相似。在最快的频率下，患有DCD的儿童步数更多，质心变异性更大，压力中心面积更大，并且比TD儿童更早且更长时间地激活他们的肌肉。患有DCD的儿童在长时间暴露于平台运动后并没有改变他们的姿势反应，然而随着任务难度的增加，他们在中外侧方向上进行了更多非结构化的姿势调整。在较快的振荡频率下，患有DCD的儿童采用了与TD儿童不同的肌肉募集策略。更早且更长时间地激活他们的肌肉可能表明患有DCD的儿童试图预测姿势干扰并做出反应，然而由此产生的预期肌肉兴奋模式似乎不像TD儿童所表现的那样能很好地适应干扰。未来的研究应该考察平衡训练干预对患有DCD的儿童肌肉募集策略的影响，以确保能够开出最佳的干预方案。
