Article

When accelerating continuously, humans spontaneously change from a walking to a
running pattern by means of a walk-to-run transition (WRT). Results of previous
studies indicate that when higher treadmill accelerations are imposed, higher
WRT-speeds can be expected. By studying the kinematics of the WRT at different
accelerations, the underlying mechanisms can be unravelled. 19 young, healthy
female subjects performed walk-to-run transitions on a constantly accelerating
treadmill (0.1, 0.2 and 0.5 m s(-2)). A higher acceleration induced a higher
WRT-speed, by effecting the preparation of transition, as well as the actual
transition step. Increasing the acceleration caused a higher WRT-speed as a
result of a greater step length during the transition step, which was mainly a
consequence of a prolonged airborne phase. Besides this effect on the transition
step, the direct preparation phase of transition (i.e. the last walking step
before transition) appeared to fulfil specific constraints required to execute
the transition regardless of the acceleration imposed. This highlights an
important role for this step in the debate regarding possible determinants of
WRT. In addition spatiotemporal and kinematical data confirmed that WRT remains a
discontinuous change of gait pattern in all accelerations imposed. It is
concluded that the walk-to-run transition is a discontinuous switch from walking
to running which depends on the magnitude of treadmill belt acceleration.

Langue : ANGLAIS