Davis W E, Sinning W E
a Kent State University.
J Mot Behav. 1987 Mar;19(1):130-44. doi: 10.1080/00222895.1987.10735404.
An attempt was made to determine the effects of strength training on elbow flexor stiffness of Down syndrome, non-Down syndrome mentally handicapped, and nonhandicapped subjects. It was hypothesized that stiffness would be affected by the training. Results showed that only half of the individual subjects increased their maximum voluntary contraction (MVC) level as a result of the training and that premeasures and postmeasures of MVC were not significantly different for any of the three groups. As expected, for both premeasures and postmeasures, nonhandicapped subjects had a significantly higher MVC than the other groups who were not significantly different. An important finding was that measures of stiffness (slopes of the IEMG × Torque) were not significantly different for the three groups. This finding is consistant with recent studies (Davis & Kelso, 1982; Shumway-Cook & Woollacott, in press) but raises serious doubts about the popularly held opinion that Down syndrome individuals are hypotonic. It was also found that both the Down syndrome and other mentally handicapped subjects produced significantly less torque at the maximum level than the nonhandicapped subjects. These findings suggest that deficits in mentally handicapping conditions result from a decrease in the range of a primary motor control parameter λ (see Feldman, 1986).
研究试图确定力量训练对唐氏综合征患者、非唐氏综合征智力障碍患者以及非残疾受试者肘屈肌僵硬度的影响。研究假设训练会影响僵硬度。结果显示，训练后只有半数个体受试者提高了其最大自主收缩（MVC）水平，且三组受试者的MVC预测量和后测量值均无显著差异。正如预期的那样，无论是预测量还是后测量，非残疾受试者的MVC均显著高于其他两组，而后两组之间无显著差异。一个重要发现是，三组受试者的僵硬度测量值（肌电图×扭矩的斜率）无显著差异。这一发现与近期研究（戴维斯和凯尔索，1982年；舒姆韦 - 库克和伍拉科特，即将发表）一致，但引发了人们对普遍认为唐氏综合征个体肌张力低下这一观点的严重质疑。研究还发现，唐氏综合征患者和其他智力障碍受试者在最大水平时产生的扭矩明显低于非残疾受试者。这些发现表明，智力障碍情况下的功能缺陷是由主要运动控制参数λ的范围减小所致（见费尔德曼，1986年）。
