Which phase includes plantar flexion with concentric plantar flexors?

Which phase includes plantar flexion with concentric plantar flexors?

• A. Pre swing
• B. Initial swing
• C. Midswing
• D. Terminal stance

Answer: (A)

The key idea is when the plantarflexor muscles actively shorten to push off the ground. During the pre-swing phase, the gastrocnemius and soleus contract concentrically to plantarflex the ankle, producing the toe-off that propels the body forward and begins the limb’s swing. This is the moment in the gait cycle where active plantarflexion by the plantarflexors drives propulsion and initiates forward progression into swing. In other phases, the ankle movement serves different tasks: initial and mid-swing are dominated by dorsiflexion to clear the foot, and terminal stance focuses on finishing propulsion rather than initiating it.

The key idea is when the plantarflexor muscles actively shorten to push off the ground. During the pre-swing phase, the gastrocnemius and soleus contract concentrically to plantarflex the ankle, producing the toe-off that propels the body forward and begins the limb’s swing. This is the moment in the gait cycle where active plantarflexion by the plantarflexors drives propulsion and initiates forward progression into swing.

In other phases, the ankle movement serves different tasks: initial and mid-swing are dominated by dorsiflexion to clear the foot, and terminal stance focuses on finishing propulsion rather than initiating it.