Article

Our goal was to determine how age and walking speed affect metabolic cost of
walking (C(w)), lower, extremity antagonist coactivation, and relationships
between coactivation and C(w) in healthy, active, individuals. Fourteen young
(25+/-3 years) and 14 older (71+/-4 years) participants walked on a treadmill at,
four speeds (0.89, 1.12, 1.34, and 1.57 m s(-1)) while electromyography (EMG) and
oxygen consumption, were measured. Coactivation indices were calculated for
musculature about the thigh and shank. C(w), was higher in older adults across
all speeds (p<0.001). Coactivation about the thigh was also higher in, older
adults (p<0.001), whereas coactivation about the shank was not different between
age groups (p=0.60). Total coactivation (thigh coactivation plus shank
coactivation) showed significant positive, relationships to C(w) at all walking
speeds (r=0.46-0.57). Higher C(w) and coactivation in older adults, along with
the positive relationship between C(w) and coactivation implies coactivation
contributes to, higher C(w) of older adults.
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Langue : ANGLAIS