According to
Textbook of Natural Medicine (2020)
Hydrotherapy is a form of physical medicine using the therapeutic application of water in a variety of ways, both internally and externally, on the body. Topical applications of cold or hot water packs, compresses, baths, pools, steams, sweats, showers, enemas, and colonics are all forms of hydrotherapy.
Profound, multisystem physiological effects result from the thermodynamic property of water and its effects on an organism's circulation and capability to remove waste and eliminate. Hydrotherapy techniques applied to a patient are a form of stress to the cells that influences their metabolic function, regulates their environment, and provides an opportunity for the body's natural healing processes to take place.
Hydrotherapy has been used by human civilizations for thousands of years and has grown to have literature demonstrating scientific evidence-based applications and uses worldwide today.
Notable proponents of hydrotherapy include:
- Father Sebastian Kneipp
(Germany).
- Benedict Lust
(Patient of Father Kneipp, who brought "water cure") to the United States.
- John Harvey Kellogg
(who founded a hospital using hydrotherapy in Battle Creek Michigan, but is more famous today for Kellogg's Corn Flakes)