Article

Previous research on the biomechanics of stair negotiation has ignored the effect
of the approaching speed. We examined if initiating stair ascent with a
comfortable self-selected speed can affect the lower-extremity joint moments and
powers as compared to initiating stair ascent directly in front of the stairs.
Healthy young adults ascended a custom-built staircase instrumented with force
platforms. Kinematics and kinetics data were collected simultaneously for two
conditions: starting from farther away and starting in front of the stairs and
analyzed at the first and second ipsilateral steps. Results showed that for the
first step, participants produced greater peak knee extensor moment, peak hip
extensor and flexor moments and peak hip positive power while starting from
farther away. Also, for both the conditions combined, participants generated
lesser peak ankle plantiflexor, greater peak knee flexor moment, lesser peak
ankle negative power and greater peak hip negative power while encountering the
first step. These results identify the importance of the starting position in
experiments dealing with biomechanics of stair negotiation. Further, these
findings have important implications for studying stair ascent characteristics of
other populations such as older adults.
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Langue : ANGLAIS