Article

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.
CI - Copyright (c) 2014 Elsevier B.V. All rights reserved.

Langue : ANGLAIS