Contrast bath therapy involves soaking an injured area in alternating hot and cold water baths to increase blood flow and decrease joint stiffness. The temperature changes from hot to cold and back again produce a "pumping effect" that helps remove swelling through improved venous and lymphatic drainage. A full contrast bath treatment consists of soaking in warm water for 10 minutes, cold water for 1 minute, repeated three times, ending with warm water. Contrast baths can help relieve pain, stiffness and swelling through induced vasodilation and vasoconstriction of blood vessels.