Hydrotherapy - Hydrotherapeutic Mechanisms and Modern Medicine

Hydrotherapeutic Mechanisms and Modern Medicine

Modern medicine's successes, particularly with drug therapy, removed or replaced many water-related therapies during the mid-20th century. Nowadays, water therapy may be restricted to use in physical therapy, and as a cleansing agent. However, it is also used as a medium for delivery of heat and cold to the body, which has long been the basis for its application.

Hydrotherapy involves a range of methods and techniques, many of which use water as a medium to facilitate thermoregulatory reactions for therapeutic benefit. While the physiological mechanisms were initially poorly understood, the therapeutic benefits have long been recognised, even if the reason for the therapeutic benefit was in dispute. For example, in November 1881, the British Medical Journal noted that hydropathy was a specific instance, or "particular case", of general principles of thermodynamics. That is, "the application of heat and cold in general", as it applies to physiology, mediated by hydropathy. In 1883, another writer stated "Not, be it observed, that hydropathy is a water treatment after all, but that water is the medium for the application of heat and cold to the body". Thus, the "active agents in the treatment (are) heat and cold", of which water is little more than the vehicle, and not the only one".

With improved knowledge of physiological mechanisms, practitioners wrote specifically of the use of hot and cold applications to produce "profound reflex effects", including vasodilation and vasoconstriction. These cause changes in blood flow and associated metabolic functions, via physiological mechanisms, including those of thermoregulation, that are these days fairly well understood, and which underpin the contemporary use of hydrotherapy. Although standard anatomy and physiology textbooks make only passing reference, if any, to hydrotherapy, some of the best descriptions of the underlying physiology upon which hydrotherapy relies, are to be found in such textbooks. For example, one of the best succinct descriptions of blood redistribution (which is fundamental to the above-mentioned reflex reaction), quoted below, is from a standard textbook.

...by constricting or dilating arterioles in specific areas of the body, such as skeletal muscles, the skin, and the abdominal region, it is possible not only to regulate the blood pressure but also to alter the distribution of blood in various parts of the body.

British and other hydrotherapy establishments are discussed from another standpoint in a recent history of psychiatry.