Three simple types of waves ripple through the body each time it moves. Transverse waves, Longitudinal Waves and Torsion Waves. Practically speaking every movement is a complex mixture of these types. To visualise these waves here are 4 diagrams. The first 2 illustrate Longitudinal and Transverse waves. The second 2 illustrate combinations of those first 2 within a fluid and within a solid.
Particles in a Longitudinal Wave move backwards and forwards. Particles in a Transverse wave move up and down. Particles in a Fluid wave move in clockwise closed curve. Particles in a Solid wave move in anti-clockwise closed curve.
All of these waves transmit power from left to right. Turn the pictures on their side in your mind to relate to body movement.
Mixed in with Torsion waves, these last two composite types of waves both occur in the body. In the trunk the more fluid front and the more solid back express these two clearly.