How do human arms and legs move when walking?

1. Legs: The legs move in an alternating fashion. One leg swings forward from the hip while the knee and ankle flex, then extends to push off the ground. Simultaneously, the other leg supports the body's weight and then swings forward. This involves the coordinated action of muscles contracting and relaxing around the hip, knee, and ankle joints.
2. Arms: The arms swing in opposition to the legs. For example, as the right leg swings forward, the left arm swings forward, and vice versa. This counter-rotation helps maintain balance and reduces the rotational forces on the torso, making walking more efficient.

This synchronized movement of limbs is controlled by the central nervous system, allowing for stable and efficient locomotion.