Which of the following is a commonly listed benefit of thermotherapy?

• A. Increased elasticity, extensibility, and flexibility of tissues
• B. Decreased elasticity
• C. Increased pain
• D. Decreased blood flow

Answer: (A)

Thermotherapy raises tissue temperature, making collagen-rich tissues more pliable. As heat increases, the fibers loosen and tissue viscosity decreases, allowing greater stretch and improving elasticity, extensibility, and overall flexibility. This is why heat is commonly used before stretching or ROM activities—to help tissues move more freely and reduce stiffness. While heat can also promote blood flow and help lessen muscle spasm and pain, the option that highlights improved tissue elasticity and extensibility best captures the typical benefit of thermotherapy. Decreasing elasticity would mean stiffer tissues, which isn’t a benefit; increased pain or decreased blood flow contradict the usual physiological effects of heating the area.