Objective: To examine whether non-heat acclimatized (NHA) emergency responders endure greater physiological and perceptual strain than heat acclimatized (HA) counterparts in tropical field settings.
Methods: Eight HA and eight NHA men urban search and rescue personnel had physiological and perceptual responses compared during the initial 4 hours shift of a simulated disaster in tropical conditions (ambient temperature 34.0 8C, 48% relative humidity, wet bulb globe temperature [WBGT] 31.4 8C).
Results: From the 90th minute through to end of shift, HA (38.5 8C) sustained a significantly higher gastrointestinal temperature than NHA (38.1 8C) (mean difference 0.4±0.2 8C, 95%confidence interval [CI] 0.2 to 0.7 8C, P=0.005) despite comparable heart rate (P=0.30), respiratory rate (P=0.88), and axilla skin temperature (P=0.47). Overall, perception of body temperature was similar between cohorts (P=0.87).
Conclusions: The apparent tolerance of greater physiological strain by HA responders occurred in the absence of perceptual differences.
|Number of pages||7|
|Journal||Journal of Occupational and Environmental Medicine|
|Publication status||Published - 2016|