Pivot slips are done by extending the legs, unweighting and flattening the skis which allows them to pivot across the fall line. Note that the uppper body maintains a position facing down the fall line while the legs and skis pivot under the body. The counter rotation of the body and legs creates a dynamic tension in the muscles of the back and abdomen which aids in the pivoting of the legs as the skis flatten against the snow. This can be compared to the back swing in a golf stroke. The arms are held widely apart which helps to prevent rotation of the upper body by the momentum of the legs. Note the relaxed and curved spine which allows the counter rotation of the legs and body.