Fixed Wet-Bulb Cut-Offs Against Individual Heat Tolerance: A Short Communication on the Evidence Gap
DOI:
https://doi.org/10.5281/zenodo.22549212Keywords:
Wet-bulb globe temperature, Exertional heat illness, Heat tolerance, Heat acclimatisation, Heat safety policy, Individual variabilityAbstract
Fixed wet-bulb globe temperature thresholds are widely used to guide decisions to modify, delay, or
cancel sporting activity, and are embedded in multiple professional society position statements and
consensus documents. This threshold approach, however, applies a single environmental cut-off
uniformly across athletes whose individual heat tolerance varies substantially according to fitness, heat
acclimatisation status, age, body composition, and sex, factors the physiological and epidemiological
literature has long shown to meaningfully shape individual heat-illness risk at any given environmental
condition. This short communication examines the evidence gap between the individual-variability
literature and current fixed-threshold heat-safety policy, and considers what a more individualised
risk-stratification approach might add without abandoning the practical simplicity that has made fixed
thresholds widely adopted.
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