Aging modifies joint power and work when gait speeds are matched

© 2010 Luis Eduardo Cofré LizamaIt is well known that ankle joint power generation is reduced in healthy older adults during gait. No general consensus exists, however, as to what fundamental or core compensatory actions are made at the knee and hip joints by the older adults to compensate for this loss in ankle joint power. The failure to control, and the relatively high variability, in gait speed may account for this lack of agreement. This study investigated the effect of aging on lower limb joint power and mechanical work during gait. The gait patterns of twelve old (66.8 ± 4.5 yr) and 12 young adults (26.6 ± 2.9 yr) were recorded for a range of matched (1.0 m•s-1, 1.3 m•s-1, 1.6 m•s-1) and self-selected speeds. Matched speeds did not differ between the groups. Combining matched speeds, the older adults generated 14% less A2 power and mechanical work (p<0.05). Compared to the young adults, the older adults produced 45% more H2 peak power, 7% more H3 peak power, 35% more K3 peak power and 11% more K4 peak power (p<0.05). No significant H1 power and mechanical work differences were found. The older adults also exhibited less ankle plantar flexion, more hip flexion and anterior pelvic tilt (p