Regional variations in transepidermal water loss, eccrine sweat gland density, sweat secretion rates and electrolyte composition in resting and exercising humans

Table 3 Regional contributions to evaporative heat loss (assuming 100% evaporation) from 14 body regions during thermal loading

Site	Rest heat loss (W)	Relative contribution (%)	Exercise heat loss (W)	Relative contribution (%)
Head (face)	27.81	10.2	91.30	13.8
Hand (palm)	4.33	1.6	12.88	1.9
Hand (dorsal)	9.63	23.5	27.36	4.1
Forearm	10.97	4.0	40.58	6.1
Upper arm	15.87	5.8	36.44	5.5
Axilla	2.48	0.9	6.75	1.0
Chest	22.00	8.1	50.60	7.7
Abdomen	21.71	8.0	45.68	6.9
Back	49.88	18.3	113.12	17.1
Buttocks	14.90	5.5	20.59	3.1
Thigh	42.06	15.4	102.59	15.5
Leg	37.89	13.9	88.56	13.4
Foot (sole)	3.75	1.4	6.83	1.0
Foot (dorsal)	9.75	3.6	17.43	2.6

The mean, whole-body sweat rates under these conditions would approximate 0.4 L.h⁻¹ (rest) and 1.0 L.h⁻¹ (light-moderate intensity exercise). Calculations were performed using the regional sweat rates from Figures4 (resting states) and 5 (exercising states), an assumed heat loss of 2.43 kJ.mL⁻¹ and the surface area of each region (Table1) based upon the morphological reference adult[116].

ISSN: 2046-7648