2022 Volume 42 Pages 204-213
The aim of this study was to evaluate a performance of phase change materials （PCM） as a tool for sports icing. We examined whether skin temperatures could be maintained in the target zones around 10℃ and 20℃ of PCM. And we investigated effects of exercise-induced heat production and skinfold thickness on the skin temperature with application of PCM. Fifteen male and twelve female volunteers were randomly divided into 10℃ or 20℃ cooling treatment groups or the control group （C10, C20, and NC, respectively） . The participants performed five sets of eight arm curl exercises with the non-dominant arm at the workload of 8 RM. Participants' dominant arms served as controls. In the cooling treatment group, PCM packs adjusted to maintain its surface temperatures at a constant temperature of 10℃ for C10 and 20℃ for C20, was applied over the skin surface above the biceps brachii of both upper-arms with a thermal insulation cover for 20 minutes after arm curl exercises. Skin temperatures at three sites in PCM applied area of both arms were monitored by using thermistors. Skin temperatures were acutely decreased in C10 and C20, and were maintained at approximately 10-12℃ （non-dominant arm: 11.0±0.1℃, dominant arm: 9.2±0.2℃） and 20-23℃ （non-dominant arm: 22.2±0.1℃, dominant arm: 20.3±0.1℃） , respectively. It is suggested that PCM would be beneficial to make tools for sports icing, although the decrease in skin temperature was tended to be affected by heat produced with the exercise and the degree of skinfold thickness.
