Heat and ice are the two most common types of passive, non-invasive, and non-addictive therapies. Heat and cold can be used alternatively and are often used as a prelude to exercise therapy.

• Heat therapy produces vasodilation: drawing blood into the target tissues. Increased blood flow delivers needed oxygen and nutrients, and removes cell wastes. The warmth decreases muscle spasm, relaxes tense muscles, relieves pain, and can increase range of motion.
• Cold therapy produces vasoconstriction, which slows circulation reducing inflammation, muscle spasm, and pain.