The purpose of this project was to evaluate different clothing fabrics in simulated hypothermic conditions. Backpacking (internal frame 20% bw) was performed on a treadmill for 30 minutes (0% grade, 4.83 km•h-1) followed with 10 minutes rest in an environmental chamber (7°C, 50% rh), on three separate occasions, while subjects wore a water saturated (27 °C) wicked synthetic, transition synthetic, or cotton shirt. Protocols [A] wind = 16 km•h-1 and [B] no wind = 4.83 km•h-1 (match walking speed) were completed by ten males (age = 24.3 ± 2.6 yr) and ten females (age = 26.0 ± 4.3 yr). Changes in skin temperature (chest, back, arm) were measured using an MP100 System (BIOPAC Systems, Inc., Santa Barbara, CA) and recorded every minute. Subjective responses (ratings on thermal sensation, clothing comfort, skin wettedness) were recorded every 5 minutes. Repeated measures ANOVA with Bonferroni post hoc tests compared temperature differences and subjective data were analyzed using the Friedman test. During protocol A, significant differences [F (2, 106) = 7.07, p < .001, h2 = .12] were found for back temperature indicating the wicked shirt had higher (warmer) values. Significant subjective responses were found for thermal sensation (c2 = 10.13, p = .006) indicating the transition shirt was perceived warmer. Significant subjective sensations were found for clothing comfort (c2 = 61.69, p < .001) and skin wettedness (c2 = 46.36, p < .001) indicating the wicked shirt was perceived more comfortable and dryer. During protocol B, significant differences [F (2, 118) = 7.09, p = .001, h2 = .11] were found for chest temperature indicating the wicked shirt had higher (warmer) values. Significant differences [F (2, 118) = 85.97, p < .001, h2 = .59] were found for arm temperature indicating that the transition had higher (warmer) values. Significant subjective responses were found for thermal sensation (c2 = 74.04, p < .001) indicating the transition shirt was perceived warmer. Significant subjective sensations were found for clothing comfort (c2 = 66.01, p < .001) indicating the wicked and the transition were perceived more comfortable than the cotton shirt. Significant subjective sensations were found for skin wettedness (c2 = 38.06, p < .001) indicating the wicked shirt was perceived dryer. The results verify that wicked synthetic and/or transition fabrics are comfortable and feel warm while reducing chill in a cold, wet environment.
This project was supported by a grant from Mountain Hardwear.