Article

Older adults commonly report muscle fatigue, which may be associated with reduced
walking ability. Elderly may have insufficient awareness of the balance threat
caused by muscle fatigue. The aim of this study was to analyze the interaction
effects of aging and leg muscle fatigue on gait parameters in walking and
obstacle crossing. One hundred and twenty men, who were divided in six groups
according to their age (20-29 years, 30-39 years, 40-49 years, 50-59 years, 60-69
years, above 70 years), participated in this study. Participants performed three
trials of unobstructed level ground walking and obstacle crossing during walking
before and after quadriceps muscle fatigue. To induce fatigue, participants
performed a repeated sit-to-stand task from a chair with arms across the chest to
a pre-determined cadence (30 cycles/min) using a metronome. Spatial-temporal gait
parameters (stride length, duration, and speed, step width, and trailing and
leading heel-clearance) were analyzed, and compared by two-way ANOVA (group and
fatigue). The results confirmed our hypothesis, showing age-related effects of
leg muscles fatigue in both gait conditions. From 40 years old, participants
modulated spatial-temporal and vertical impulses in both tasks more in response
to fatigue than younger participants, apparently to improve balance and safety.
Leg muscle fatigue caused age-dependent changes in both unobstructed level ground
walking and obstacle crossing during walking, which appeared to reflect an
attempt to maintain balance and safety, probably to counteract adverse fatigue
effects.
CI - Copyright (c) 2014 Elsevier B.V. All rights reserved.

Langue : ANGLAIS