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

Table 2 Regional distributions of physiologically active eccrine sweat glands, skin surface areas, gland counts and glandular dimensions

Site	Density (glands.cm⁻²)	Surface area (%)	Surface area (cm²)	Gland count	Gland mass (g)	Gland length (m)
Head	186	7.43	1,342.5	250,021	8.8	1,531.4
Hand (palm)	518	1.81	327.0	169,478	5.9	1,038.1
Hand (dorsal)	166	2.83	511.4	85,153	3.0	521.6
Forearm	104	5.98	1,080.5	112,836	3.9	691.1
Upper arm	91	8.22	1,485.2	134,858	4.7	826.0
Axilla	84	1.09	196.2	16,472	0.6	100.9
Chest	94	7.60	1,374.0	129,742	4.5	794.7
Abdomen	102	7.47	1,349.7	138,315	4.8	847.2
Back	103	12.42	2,244.1	231,408	8.1	1,417.4
Buttocks	37	5.09	919.7	33,751	1.2	206.7
Thigh	69	19.86	3,588.4	246,994	8.6	1,512.8
Leg	57	13.66	2,468.2	141,299	4.9	865.5
Foot (sole)	497	2.90	524.0	260,354	9.1	1,594.7
Foot (dorsal)	119	3.64	657.7	78,272	2.7	479.4
Totals			18,070.2	2,028,954	71.0	12,427

All calculations are normalised to the unisexual, morphological reference adult (70.0 kg, 1.702 m, body surface area 1.807 m²[116]). Relative surface areas were obtained from Yu et al.[110], with absolute hand and foot areas from Yu and Tu[117] and Hsu and Yu[118]. Assumptions: The chest and abdomen were assumed to be 50% of the anterior trunk; the anterior neck was added to the chest; each axilla was estimated to be 60% of palmar size, and this was subtracted from the chest; the posterior neck was added to the back. Calculations: Glandular mass calculations were based upon a mean mass of 35 μg[7]. Glandular length (6.1 mm) was based upon a secretory coil length of 3.5 mm long[54] and the assumption that the downstream duct is 75% of this length[3].

ISSN: 2046-7648