Hydrotherapy is the local application of water for therapeutic purposes. In other words, it consists of the external application of water on skin and mucous membranes, either all over the body, as in the case of a bath or immersion, or to a specific part of the body, such as in the pediluvium or cold shower for legs or feet.
This treatment is sometimes confused with crenotherapy, but the former is part of the latter, which also involves drinking the water, also known as hydropinia.
The skin and mucous membranes absorb the chemical elements contained in the water. Therefore, if the water used is mineral-medicinal, in other words, if it is water with proven curative properties, the effect is much better. The running water treatments provided by spas are also beneficial for their mechanical (flow, pressure) and thermal properties.
Hydrotherapy techniques include baths in a thermal pool, in jacuzzi or in a whirlpool tub; steam baths; all kinds of showers; underwater massages with water jets or air pressure jets; walking against water currents; massages with wet towels; application of muds, seaweed, paraffins and other wet substances, and inhalations.
In terms of baths, they can be simple —cold or hot, or cold and hot, also known as contrasting—, dynamic —with air bubbles, submerged jets of high pressure water or in waterfalls, with currents, etc.— , galvanic or combined with electricity, with additives, combined with exercises such as aquagym and swimming, etc.
Hydrotherapy has innumerable therapeutic applications. The most common, however, are for traumatisms, rheumatism and skin, respiratory and neurological illnesses.