This paper presents a meticulous analysis of the alterations in the human body’s center of gravity and static friction during movement. The objective is to comprehend the autonomous locomotion of the human body without external propulsion or tension. A wave theory model is proposed to elucidate the fundamental process of human motion on the ground. By considering one foot as a fulcrum, the other foot functions as a lever, generating torque and propelling the forward movement of the human body. The force model of an individual is affected by the vertical gravitational force-rebound force and the horizontal forward static friction force-backward static friction force. These forces exhibit a cosine wave pattern, with a 90-degree phase difference (at maximum efficiency). The achievement of horizontal movement necessitates vertical movement, reflecting a unique principle that enhances comprehension of the occurrence of relative displacement or force between two objects.