Human movement is beautiful and complex. It is not linear and does not happen in a single plane. When you combine two or more planes of movement, the movement is spiral, or more precisely, helical in nature, like the DNA helix.
Fascia, the predominant tissue in our structure, is a potential spring. Fascia stores and releases elastic energy, which reduces the amount of muscular effort the body needs to move. This energy is expressed through spirals. I’ve coined this integration between three-dimensional movement and the fascial spring, The Spiral Engine of Locomotion TM .