Joint Powers
Significant differences in peak joint powers at the hip and ankle were evident between the groups (table 4). Compared
with the healthy elders at a comfortable gait speed, the lowperformance group generated significantly less ankle plantarflexor power (A2) during late stance but greater hip extensor power (H1) during early support at a comfortable walking speed (see fig 2). To walk faster, peak joint power generation and absorption increased significantly at the ankle, knee, and hip. Ankle power output during late stance increased an average of 23% with speed, whereas hip peak flexor power generation (H1), absorption (H2), and extensor power generation (H3) increased an average of 54%, 57%, and 67%, respectively, at the fast walking speed. Despite walking much faster than the healthy elderly adults, ankle power generation during fast gait remained significantly below the ankle power output of the healthy elders at a comfortable gait.