Effects of Heat Increases cellular metabolism. Increases muscle spindle activity. Increases muscle contractility. Increases inflammatory response. Increases extensibility of collagen.
Increases nerve conduction velocity.
Reduces synovial fluid viscosity. The therapeutic results of these effects are a reduction in pain and muscle spasm, an increase in circulation, more mobile connective tissue, and a general feeling of relaxation and well-being. When attempting to use superficial heating modalities on a horse, attention to task is necessary to avoid over-heating the skin and to provide sufficient deep heat to accomplish the treatment goals. Heat applied too soon after injury will increase the inflammation, swelling, and pain. Heat is contraindicated in acutely inflamed joints or soft tissue, but can be safely applied when there is no increase in the swelling over a 24-hour period.