Electrotherapy is a form of physical therapy treatment when electrical stimulation is applied to nerves and muscle-motor fibers through electro-pads placed on the skin. There are a few types of electrotherapeutic devices used by rehabilitation clinics, with T.E.N.S. (Transcutaneous Electrical Nerve Stimulation) being the most popular. These treatments block the transmission of pain signals along the nerves. In addition to this electrical stimulation promotes the release of endorphins, which are natural painkillers in the body.