Cryotherapy is best defined as the therapeutic use of cold accomplished by applying a device or substance cooler than what?

• A. Cooler Than Body Temperature
• B. Warmer Than Body Temperature
• C. As Warm As Body Temperature
• D. Slightly Above Body Temperature

Answer: (A)

Cryotherapy relies on creating a heat transfer from the body's tissues to a cooler medium. By using a device or substance that is cooler than body temperature, a temperature gradient is established so heat flows out of the tissues. This cooling produces vasoconstriction, lowers cellular metabolism, and slows nerve conduction, which helps with analgesia and reduces swelling. If the cooling medium were warmer than body temperature, it would heat the tissue instead, and if it were at body temperature, there would be little to no heat transfer. Thus, using something cooler than body temperature is essential to achieve the therapeutic cooling effect.