Almeida G L, Corcos D M, Latash M L
Universidade Estadual de Campinas, Instituto de Reabilitação de Campinas, São Paulo, Brazil.
Phys Ther. 1994 Nov;74(11):1000-12; discussion 1012-6. doi: 10.1093/ptj/74.11.1000.
The purpose of this study was to investigate the effects of prolonged practice of a simple motor task (a fast, unidirectional single-joint movement) on different indexes of motor performance in individuals with Down syndrome.
Eight individuals with Down syndrome were tested before and after practice involving 1,100 movements.
The test consisted of three series of elbow flexion movements. In the first series, the subjects were asked to move "as fast as possible" over four distances. In the second series, the subjects moved over one distance at a "comfortable speed." The initial position of the elbow joint for these two series of movements was 55 degrees into flexion (full elbow extension equals 0 degrees). In the third series, the subjects were also asked to move "as fast as possible" over two distances, but from another initial elbow position (73 degrees into flexion).
After training over a 2-week period, all subjects improved their performance on all tasks as reflected by both kinematic and electromyographic data. In particular, they increased the quantity of the agonist activity, decreased the antagonist onset latency, and doubled their peak velocity. They were able to transfer the improvement in their performance to the nontrained distances and to the different starting position. Subjects decreased their movement time by proportionally decreasing both the acceleration and deceleration times.
This study supports the idea that subjects with Down syndrome can use patterns of muscle activation that are qualitatively indistinguishable from those used by individuals who are neurologically normal. With appropriate training, individuals with Down syndrome achieved similar levels of motor performance to that described in the literature for individuals who are neurologically normal.
本研究旨在调查长期练习一项简单的运动任务（快速、单向单关节运动）对唐氏综合征患者不同运动表现指标的影响。
八名唐氏综合征患者在进行涉及1100次运动的练习前后接受了测试。
测试包括三组肘部弯曲运动。在第一组中，要求受试者在四个距离上“尽可能快地”移动。在第二组中，受试者以“舒适的速度”在一个距离上移动。这两组运动中肘关节的初始位置为屈曲55度（肘关节完全伸展等于0度）。在第三组中，受试者同样被要求在两个距离上“尽可能快地”移动，但起始肘关节位置不同（屈曲73度）。
经过为期两周的训练后，所有受试者在运动学和肌电图数据方面均显示出在所有任务上的表现有所改善。具体而言，他们增加了主动肌活动量，缩短了拮抗肌起始潜伏期，并且峰值速度提高了一倍。他们能够将表现上的改善转移到未训练的距离以及不同的起始位置。受试者通过按比例缩短加速和减速时间来减少运动时间。
本研究支持这样一种观点，即唐氏综合征患者能够使用与神经功能正常个体在质量上无法区分的肌肉激活模式。通过适当的训练，唐氏综合征患者达到了与文献中所描述的神经功能正常个体相似的运动表现水平。
