The use of the physical agents in the treatment of disease or injury. The most frequently used of these agents are (1) hydrotherapy: water applied at various temperatures and pressures; (2) exercise; (3) rest; (4) massage; (5) light therapy: sunlight and artificial radiation including visible, infrared, and ultraviolet radiations; (6) electrotherapy: low voltage direct and alternating currents and the high frequency currents including shortwave and microwave diathermy; (7) ultrasonic therapy: high-frequency sound waves. Physical therapy is best administered by professionally trained and registered physical therapists. It may also be applied by graduate nurses who have had training in this field. Physical Medicine. When physical therapy is administered on the prescription and under the supervision of a physician trained in physical medicine and rehabilitation (psychiatrist), it is more properly called physical medicine. Rehabilitation is a comprehensive multidisciplinary program aimed at restoring persons to the maximum of their recovery potential. Physical therapy is an essential feature of the rehabilitation program. Early in the history of the movement, Seventh-day Adventists became a health-conscious people ( see Health Principles ). In the middle of the nineteenth century, as the Seventh-day Adventist Church emerged and began developing, the science of pharmacology was in its infancy. Potent drugs such as mercury, strychnine, and the opiates were prescribed empirically in large dosages. (Today, mercury and strychnine are obsolete as therapeutic agents for internal administration, and the opiates are used sparingly.) Against this background developed a growing interest in the physiologic approach to treatment by “natural” or “physical” agents. During the first half of the nineteenth century, the Austrian peasant Priessnitz popularized hydrotherapy in Europe. Physical therapy, although not designated by that term in the mid-nineteenth century, was not entirely new. Various physical therapy procedures had been employed intermittently since the time of Hippocrates (460–357 B.C.). In 1648 a Seventh Day Baptist physician, Dr. Peter Chamberlen (1601–1683), proposed a system of hydrotherapeutics in public baths in England, but was turned down by the College of Physicians. A few years after Priessnitz’ work, Professor Winternitz, of Vienna, placed hydrotherapy on a scientific footing. Contemporaneously in the United States there were physicians interested in the reform of existing medical practice. One of these was Dr. J. C. Jackson, who operated the Health Institute at Dansville, New York. Another was Dr. R. T. Trall, who conducted the Hygio-Therapeutic College, at Florence Heights, New Jersey. Both of these men influenced in some degree the early development of the treatment program of Seventh-day Adventist medical institutions. Under the inspiration of Ellen White, the Western Health Reform Institute, later known as the Battle Creek Sanitarium, was founded in the fall of 1866. In the institute drugs were not prescribed, but patients were treated with rest, exercise, hydrotherapy, and a vegetarian diet. In 1876 Dr. J. H. Kellogg became medical superintendent of the institute. During his long tenure he did a considerable amount of experimental study of the physical therapy procedures. The Battle Creek Sanitarium became famous the world over for its physical therapy program and its vegetarian diet. Before the Battle Creek Sanitarium was removed from church control, about 1908, other sanitariums were being established by the denomination, under the guidance of Ellen White and Dr. Kellogg in other parts of the United States and in foreign lands, and in each of them physical therapy became a prominent feature of the treatment program. One of the largest of these institutions was the Skodsborg Sanitarium near Copenhagen, Denmark. At present many Seventh-day Adventist hospitals continue to operate an active physical therapy department. Along with other advances in medicine, newer methods of treatment are used, often in the broader context of physical medicine and rehabilitation. Loma Linda University School of Allied Health offers undergraduate and graduate training in physical therapy. In 1941 a School of Physical Therapy was established at Loma Linda in connection with the School of Medicine for the training of qualified physical therapists. A fully approved school with a degree course, it has one of the largest enrollments among approved physical therapy schools in the United States. Andrews University now also operates an accredited School of Physical Therapy. In 1947 the American Medical Association established a qualifying Board of Physical Medicine and Rehabilitation for physicians who specialize in this field, which includes physical therapy. Some of the larger SDA hospitals have board-qualified specialists in physical medicine and rehabilitation, known as physiatrists, who have charge of this phase of the treatment program. Most Seventh-day Adventist hospitals have physical therapy services in their institutions.