During terminal stance and pre-swing, the ground reaction force is positioned where relative to the ankle axis?

During terminal stance and pre-swing, the ground reaction force is positioned where relative to the ankle axis?

• A. Posterior to the axis
• B. Far anterior to the axis
• C. Directly through the axis
• D. Medial only

Answer: (B)

In this part of the gait cycle, the weight is carried by the forefoot as you prepare to push off. The ground reaction force from the surface acts through the forefoot and, in terminal stance and pre-swing, its line of action sits well in front of the ankle joint axis. This forward (anterior) position creates an external moment about the ankle that aids propulsion toward toe-off, working with the calf muscles to push you forward. If the force were actually through the ankle axis, there would be little external moment to drive propulsion. If it fell behind the axis, the force would tend to oppose forward progression. Being positioned far anterior to the axis matches the functional need to propel the body forward at the end of stance.

In this part of the gait cycle, the weight is carried by the forefoot as you prepare to push off. The ground reaction force from the surface acts through the forefoot and, in terminal stance and pre-swing, its line of action sits well in front of the ankle joint axis. This forward (anterior) position creates an external moment about the ankle that aids propulsion toward toe-off, working with the calf muscles to push you forward.

If the force were actually through the ankle axis, there would be little external moment to drive propulsion. If it fell behind the axis, the force would tend to oppose forward progression. Being positioned far anterior to the axis matches the functional need to propel the body forward at the end of stance.