Table 2.

Estimated whole body skin blood flow (SkBF) requirements^a during prolonged, severe running exercise^b at different body core (T _c) and skin (T _sk) temperatures

T c (°C)	T sk (°C)	Gradient (°C)	SkBF (L/min)
38	30	8	1.1
38	34	4	2.2
38	36	2	4.4
39	36	3	2.9

Adapted from Kenefick et al. [66], with permission

^aEquation for skin blood flow: Q _s = 1/C × h/(T _c−T _sk), where, C specific heat of blood ≈0.87 kcal/°C/L, h heat production (kcal/min), Q _s skin blood flow [43]

^bNet heat production (7.7 kcal/min) estimated using 60 kg body mass and 325 m/min running velocity (approximate pace for men’s world class 42 km footrace) after subtracting for work (20 % efficiency) and 50 % dry and evaporative heat losses