Agiovlasitis Stamatis, McCubbin Jeffrey A, Yun Joonkoo, Widrick Jeffrey J, Pavol Michael J
Department of Kinesiology, Mississippi State University, 233 McCarthy Gym, PO Box 6186, Mississippi State, MS 39762, United States.
Colorado State University, College of Health and Human Sciences, 201A LL Gibbons Building, 1501 Campus Delivery, Fort Collins, CO 80523-1501, United States.
Gait Posture. 2015 Jan;41(1):180-4. doi: 10.1016/j.gaitpost.2014.10.004. Epub 2014 Oct 12.
The altered gait patterns of adults with Down syndrome (DS) may contribute to their higher net metabolic rate (net-MR) during walking than adults without DS, leading to mobility limitations. This study examined the extent to which gait characteristics explain differences in net-MR during walking between adults with and without DS. Fifteen adults with DS (27 ± 8 years) and 15 adults without DS (28 ± 6 years) completed two testing sessions in which expiratory gases and kinematic data were collected, respectively, during treadmill walking. Participants walked at six, randomly-presented dimensionless speeds, ranging from slow to fast. Hierarchical and stepwise regressions were used to determine the proportion of the variance in net-MR explained by gait variables that differed between groups, after controlling for variance due to walking speed. Positive work rate, the range of the body center of mass (COM) mediolateral position and its square, variability in the time-course of COM anteroposterior velocity, and the variability of step length, step width, and step time significantly predicted net-MR (p < .05). These variables collectively explained 73.9% of the variance in net-MR that was explained by DS but not by walking speed. After accounting for shared variance among predictors, step length variability made the greatest unique contribution (10.6%) to the higher net-MR in adults with DS, followed by the range of COM mediolateral motion (6.3%), step width variability (2.8%), and variability in COM anteroposterior velocity (0.7%). Therefore, the gait characteristics of adults with DS appear to largely explain their higher net-MR during walking.
与无唐氏综合征（DS）的成年人相比，患有DS的成年人步态模式改变可能导致其在行走过程中净代谢率（net-MR）更高，从而导致行动受限。本研究调查了步态特征在多大程度上解释了患有和未患有DS的成年人在行走过程中净代谢率的差异。15名患有DS的成年人（27±8岁）和15名无DS的成年人（28±6岁）完成了两个测试环节，分别在跑步机行走过程中收集呼气气体和运动学数据。参与者以六个随机呈现的无量纲速度行走，速度范围从慢到快。在控制了行走速度引起的方差后，使用层次回归和逐步回归来确定由两组之间不同的步态变量解释的净代谢率方差比例。正向工作率、身体质心（COM）中外侧位置范围及其平方、COM前后速度时间进程的变异性以及步长、步宽和步时的变异性显著预测了净代谢率（p<0.05）。这些变量共同解释了由DS而非行走速度解释的净代谢率方差的73.9%。在考虑了预测变量之间的共享方差后，步长变异性对患有DS的成年人较高的净代谢率贡献最大（10.6%），其次是COM中外侧运动范围（6.3%）、步宽变异性（2.8%）和COM前后速度变异性（0.7%）。因此，患有DS的成年人的步态特征似乎在很大程度上解释了他们在行走过程中较高的净代谢率。
