Article

A major movement related limitation for children with spastic cerebral palsy (CP)
is the compromised gait pattern, which may explain their excessive energy cost of
locomotion. The aims of this study were to determine differences in the O2 cost
of locomotion between children with CP (7 males, 2 females; 12.7 +/- 2.8 yr) and
able-bodied controls (7 male, 1 female; 13.6 +/- 2.1 yr) and to assess the
contribution that cocontraction of agonist and antagonist muscles had upon the
elevated O2 cost seen in children with CP versus able-bodied controls. The
treadmill submaximal walking protocol consisted of 2 x 4 min intermittent stages
at 3 km.h-1 and 90% of the predetermined fastest walking speed (FWS) at 0% grade.
Electromyographic data were collected during the final minute of each bout from
vastus lateralis and hamstrings (thigh) and tibialis anterior and soleus (lower
leg). Significant (P < 0.05) differences were noted at 3 km.h-1 for mass-relative
VO2. (CP: 16.6 +/- 6.5 vs control: 10.2 +/- 1.2 ml.kg-1.min-1), % VO2max (CP:
53.5 +/- 26.0 vs Control: 22.5 +/- 4.93) and heart rate (CP: 143 +/- 41 vs
Control: 91 +/- 14 beats.min-1). Thigh and lower leg muscle cocontraction
accounted for 51.4% and 42.8%, respectively, of the variability in VO2 for the
subjects with CP at 3 km.h-1. These results suggest that cocontraction is a major
factor responsible for the higher energy cost of walking seen in children with CP

Langue : ANGLAIS

Tiré à part : OUI