A New Occupational Heat Tolerance Test: A Feasibility Study

This study aimed to assess the validity and reliability of a new heat occupational tolerance test (HOTT: 40 min at 6 W.kg-1 metabolic heat production, 50 °C 10% RH, in protective clothing) to the standard heat tolerance test (HTT: 2 hr walk at 5 km.hr-1 1% gradient, 40 °C 40% RH, in shorts and t-shirt). Eighteen participants (age: 21±3 yrs, body mass: 81.3±5.9 kg) completed trials to assess the validity and/or reliability of the HOTT. Peak rectal temperature (Tre) displayed strong agreement and low measurement error (0.19 °C) between HTT (38.7±0.4 °C) and HOTT (38.6±0.4 °C). Strong agreement was also displayed for physiological and perceptual measures between the two HOTT trials, including peak Tre (38.5±0.4 °C vs. 38.5±0.4 °C) and peak heart rate (182±20 b.min-1 vs. 182±21 b.min-1). The HOTT is the first tolerance test that assesses individuals’ responses whilst wearing protective clothing in high temperatures. It can consistently identify individuals’ levels of heat tolerance within a reduced time frame. In addition, it allows for participant monitoring over time and comparisons between individuals to be made. A continuum based approach is recommended when assessing individuals’ responses to the HOTT.
Source: Journal of Thermal Biology - Category: Biology Source Type: research