Assessing the Effects of Icing the Body for 20 Minutes

Abstract

Icing is one of the most inexpensive and convenient treatments available to reduce inflammation in sore and injured muscles. A commonly purported icing regimen follows a ?20 minutes on, 20 minutes off? cycle, so we investigated how much skeletal muscle cools during the 20-minute icing period. To model the temperature distribution, we used an axisymmetric geometry consisting of five layers: the ice, a plastic bag, skin, subcutaneous fat, and muscle. Our initial results showed cooling of the most superficial muscle tissue by approximately 15oC. We found that changes in properties such as density, specific heat, and conductivity did not affect temperature contours at the 20-minute time point; however, heating via perfusion, which was initially neglected, had a substantial effect on the final results. When blood flow was introduced into the model, the temperature of superficial muscle decreased only 3.5oC. We thus conclude that although icing is an effective means of cooling superficial layers of muscle, it is not particularly efficacious at increasing depths.