Convection in thermotherapy is defined as

• A. Movement of heat by circulating or moving particles
• B. Heat transfer by direct contact
• C. Radiant energy through air
• D. Heat generation within tissue

Answer: (A)

Convection in thermotherapy means heat is transported by the movement of a fluid (such as air or water). The circulating fluid carries thermal energy with it, delivering heat to tissues without requiring direct contact with a warm surface. This is different from conduction, which relies on direct contact for heat transfer; radiation, which moves energy as infrared waves through space; and internal heat generation, which comes from metabolism within the tissue. So the idea of heat moving via circulating or moving fluid best describes convection.