Hydrotherapy is the use of water for therapy, rehabilitation, exercise, relaxation and more. The unique properties of water, including the decreased effects of gravity, the effects of buoyancy, hydrostatic pressure are used by the therapist along with their diagnostic skills, exercise knowledge and other treatment techniques to enhance the recovery and rehabilitation of clients with a wide range of conditions and provide a unique environment to maintain health, well-being and fitness.

In a clinical setting the use of hot water as can be tolerated is used to relieve muscle spasm, increase blood flow and joint motion. Hydrotherapy is used successfully to ease sore muscles, relieve stress, treat burns, reduce fevers and reduce edema. Painful joint disorders such as arthritis respond well to hydrotherapy. In some clinics the arthritis program includes water therapy where the patient performs exercises in the water. Because of the buoyancy of the water, the patient expends less effort and can therefore accomplish more.