The effect of skin thermistor fixation method on weighted mean skin temperature

The purpose of this study was to investigate the effect of three different skin thermistor attachment methods on weighted mean skin temperature (WMT(sk)) at three different ambient temperatures (approximately 24 °C (TEMP); approximately 30 °C (WARM); approximately 35 °C (HOT)) compared to uncovered thermistors. Eleven, non-acclimated, volunteers completed three 5 min bouts of submaximal cycling (approximately 70 W mechanical work)-one at each environmental condition in sequential order (TEMP, WARM, HOT). One thermistor was fixed to the sternal notch whilst four skin thermistors were spaced at 3 cm intervals on each of the sites on the limbs as per the formula of Ramanathan (1964 J. Appl. Physiol. 19 531-3). Each thermistor was either held against the skin uncovered (UC) or attached with surgical acrylic film dressing (T); surgical acrylic film dressing and hypoallergenic surgical tape (TT) or surgical acrylic film dressing, hypoallergenic surgical tape and surgical bandage (TTC). The WMT(sk) calculated was significantly lower in UC compared to T, TT and TTC (p < 0.001, d = 0.46), in T compared to TT and TTC (p < 0.001, d = 0.33) and in TT compared to TTC (p < 0.001; d = 0.25). The mean differences (across the three temperatures) were + 0.27 ± 0.34 °C, + 0.52 ± 0.35 °C and + 0.82 ± 0.34 °C for T, TT and TTC, respectively. The results demonstrate that the method of skin thermistor attachment can result in the significant over-estimation of weighted mean skin temperature.