Ice or Heat part 2

Ice or Heat part 2

Superficial Heating Effects are Short Lived

Superficial heat, such as a hot pack or whirlpool, applied to the body elicits vasodilatation, pain relief, diminished muscle tone and spasticity, increases the metabolic rate of cells, and diminishes joint stiffness. Superficial heat, or thermotherapy, produces only mild increases in tissue temperatures and the duration of this temperature elevation is relatively short. This increase in tissue temperature results in an increase in local blood flow, primarily in the vessels of the skin and subcutaneous tissues. Superficial heating agents rarely penetrate to depths greater than 1 -2 cm, but ultrasound therapy can effectively penetrate up to 5 cm. Increases in blood flow to deeper tissues such as skeletal muscle usually appears to be produced by the metabolic demands of an exercising muscle and therefore produces very little change with the application of a superficial heating agent.

The local increase in blood flow also brings greater than normal amouts of oxygen and nutrients into the area. The rates of chemical reactions are dramatically increased by the rise in temperature causing a sudden and large demand for both oxygen and nutrients by the cells. If this demand is not satisfied adequately, the cells die. The vasodilatation occurs not only in the area being treated but also distal to the area. This allows for more oxygen and nutrients to reach sites distal to the injury. Superficial application of heat has been shown to decrease muscle tone that allows for diminished muscle spasms and pain. Heat also stimulates skin thermoreceptors that compete with pain impulses for transmission along nerves causing fewer pain impulses to make their way to the brain.

Heat treatments such as hot packs or warm whirlpools usually are 10 - 20 minutes in duration. Ultrasound treatments last 3 - 10 minutes but should be administered only by a Licensed Athletic Trainer, physical therapist, or physician. Heat may promote abnormal ossification of a hematoma and induce muscle fatigue. Heat treatments should not be administered unattended due to its relaxing effect and the chance of superficial burns. They should only be instituted after the risk of continued bleeding has passed or in the absence of superficial infection.

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Last Update for AthleticAdvisor.com: 10/24/2009 12:09:35 AM