The human body is an electrical circuit with points of resistance and points of conductance that constantly change depending on the condition of the body. With injury certain locations become more conductive to electricity and are used to electrically stimulate for pain, increased range of motion, quicker rehabilitation and tissue healing. Here is a nice video from arpwave using what they call a "search and destroy" methodology that works off the point location/stimulation properties of our body.
If anyone doubts this concept it can be shown by simply using an ohm meter and liteally measuring the points on the body. After finding, then stimulate, and remeasure the exact same points. One finds less pain, the acutal point is now more resistant, and for many greater range of motion. There is no hocus pocus with this naturally occurring process that our body uses for injury and illness. See video below: