Liquid Ice fails to cool the skin surface as effectively as crushed ice in a wet towel.

Physiother Theory Pract 26(6):393-8 (2010) PMID 20658925

One sought to compare surface cooling produced by two cryotherapy modalities (crushed ice in a room temperature wet towel and Liquid Ice). Twenty-five university students (10 female and 15 male) between 19 and 29 years of age (mean+/-SD: 21.36+/-2.33) participated in this study. Skin surface temperature was measured prior to, immediately after 20-minute application, and 20-minute postapplication of the cryotherapy modality using an infrared camera. Both cryotherapy modalities decreased the baseline skin surface temperature (crushed ice: 28.6+/-1.3 to 6.8+/-1.8 degrees C; Liquid Ice: 28.6+/-1.6 to 25.2+/-1.56 degrees C; p<0.001). Assuming that greater cooling seems to be better, the present results suggest that: 1) a 20-minute application of crushed ice in a room temperature wet towel is more effective at cooling skin temperature than evaporative cooling menthol-based products and 2) Liquid Ice(TM) is not a clinically useful modality.