Modeling the thermoregulatory significance of differential solar absorptance in American football helmets

Variations in the color of youth football helmets had a statistically significant (ANOVA; p < 0.001) ∽ 2-fold effect on solar absorptance, α₁ (%) in white, red, and black helmets. At the end of 30-minute of exposure to a dangerously hot outdoor environment (mean WBGT 34.3 ± 1.1 ACSM Heat-Index Black; Extreme Danger Stop Play) the internal shell temperature, T_is (°C) of red and black youth helmets were ∽ 18.7 to 20.6 °C hotter than white helmets. The objective was to use the thermal modeling to estimate the thermoregulatory significance of α₁ on net-radiant heat transfers ± Q_n (W) and heat storage, ±X and the onset of exertional heat illness EHI. Players wearing black or red helmets may experience early onset of EHI. Some players wearing black or red helmets may be more susceptible to EHI. We discuss our results in relationship to the potential effect of helmet color on EHI.