Hydrotherapy works by encouraging a full range of joint movement in a non or reduced weight bearing situation. Hydrotherapy improves muscle tone and promotes tissue repair without putting undue pressure or stress on any damaged tissue. Swimming also helps to improve general fitness and stamina, it increases cardiovascular strength and muscle tone.

Muscle wastage begins within 3 days of any inactivity, so to prevent excess loss of muscle tone following surgery or injury it is important to rebuild muscle through safe, controlled exercise.

Heated water is used to increase blood flow as opposed to swimming in cold water, which constricts the blood vessels near to the skin and also to the muscles just under the skin. Restricted blood flow makes muscles less efficient.