What happens to the gastrocnemius of your leg when the shank is flexed as in walking?

When the shank is flexed during walking, the gastrocnemius muscle, which is a major calf muscle, becomes lengthened. This occurs because the gastrocnemius crosses both the knee and ankle joints; as the knee flexes, the muscle must stretch to accommodate the movement. This lengthening allows for greater range of motion and contributes to the propulsion phase of walking. Additionally, the muscle can still function to stabilize the ankle and assist in balancing during the gait cycle.