There are three factors at work in a spa: heat, buoyancy, and massage. Together, they create a relaxing, soothing experience.
Immersion in hot water raises the body temperature and causes the blood vessels to dilate, increasing circulation. The buoyancy of the water reduces body weight by approximately 90%, which relieves pressure on joints and muscles and creates the relaxing sensation of weightlessness.
The massaging action of a hot tub is created by sending a mixture of warm water and air through jet nozzles. This "energized" stream of water loosens tight muscles and stimulates the release of endorphins, the body's natural pain killers.
Of course a hot tub offers much more than just a good hydromassage. It can also be good for your health. "Research shows that both the body and mind benefit from the simple act of immersion in warm water." The Hot Water & Healthy Living book summarizes the present knowledge about the many health benefits from immersion in water.
