3.7 Ankle kinematics during running

Examine the plot of ankle flexion angle over a gait cycle during walking (gray line) and running at various speeds (colored lines) from Figure 3.20. (The vertical lines correspond to toe off at each speed, the running gait cycle icons along the x-axis correspond to running at 2 m/s).

(a) Does the ratio of swing to stance phase increase or decrease with gait speed?

(b) Where in the walking gait cycle (gray line) does the ankle reach maximum plantarflexion? How does this compare with the timing of peak plantarflexion during running? What is the purpose of this plantarflexion?

(c) How do the peak ankle dorsiflexion and plantarflexion angles change as running speed changes?