Final Answer:
Flexion of the knee is required during walking primarily during the swing phase to clear the ground and prepare for the subsequent foot strike.
Step-by-step explanation:
Swing Phase Necessity:
During the swing phase of walking, the leg swings forward, and the knee flexes to lift the foot and ensure clearance over the ground, preventing tripping or stumbling.
Foot Positioning:
Flexing the knee during swing phase allows for sufficient clearance between the foot and the ground, enabling a smooth transition for the leg to move forward and prepare for the next step.
Energy Conservation:
Controlled flexion of the knee also aids in conserving energy during walking by facilitating a smoother, more efficient stride, reducing excessive strain on muscles and joints.
When walking, the swing phase demands knee flexion to allow the foot to clear the ground without obstruction. This flexion ensures a smooth, safe, and energy-efficient gait by aiding in foot clearance and facilitating a well-coordinated movement pattern.