NIH Module 7 – Laboratory Testing, Diagnostic Imaging, and Screening Practice Test

Moist heat in thermotherapy works best because heating the tissue with moisture transfers energy efficiently, raising tissue temperature more effectively than dry heat. This warmth causes vasodilation and increased local blood flow, bringing more nutrients and oxygen to the area while helping remove waste products that can contribute to pain. The heat also relaxes muscles and reduces muscle spasms, improving tissue pliability—especially helpful for areas with muscles and tendons. So the benefit described is that moist heat increases circulation and relieves pain, particularly in muscles and tendons.