2007, Piran, Slovenia

Environmental Ergonomics XII
Igor B. Mekjavic, Stelios N. Kounalakis & Nigel A.S. Taylor (Eds.), © BIOMED, Ljubljana 2007
2006). In addition, the distal palmar phalanges (finger pads) are the most responsive sites of
the palmar surface to thermal loading, with sweat secretion at these loci being similar to that
of the dorsal surfaces of the hand.
Whilst one may intuitively associate high sweat flows with sites of greater gland density, this
pattern is not evident for either the hand (Figure 2) or the foot (Taylor et al., 2006). Indeed,
sweat glands counts, and the number of active sweat glands per square centimetre seems to be
greater at the palm, although the thermally-induced glandular flow appears to be extremely
low at this site (Ogata, 1935).
It is clear that this limb segment cannot be assumed to behave homogeneously with regard to
its sudomotor (Figure 2) and vasomotor (Johnson et al., 1995) heat loss responses. A similar
response heterogeneity has recently been reported for the hand during cold-water immersion
(Cheung and Mekjavic, 2007). Therefore, the regional distribution of all heat loss and
conservation responses within the hand (and foot) should be considered not just by those
studying thermoregulation in humans, but also by those interested in simulating
thermoeffector responses (modellers and thermal manikin engineers), and by those who
design and manufacture hand and footwear.
REFERENCES
Cheung, SS, and Mekjavic, I.B. (2007). Cold-induced vasodilation is not homogeneous or
generalizable across the hand and feet. Eur. J. Appl. Physiol. 99(6): 701-705.
Johnson, J.M., Pergola, P.E., Liao, F.K., Kellogg, Jr., D.L., and Crandall, C.G. (1995). Skin of
the dorsal aspect of human hands and fingers possesses an active vasodilator system. J.
Appl. Physiol. 78(3): 948-954.
Ogata, K. (1935). Functional variations in the human sweat glands, with remarks upon the
regional difference of the amount of sweat. J. Oriental Med. 23:98-101.
Taylor, N.A.S., Caldwell, J.N., and Mekjavic, I.B. (2006). The sweating foot: local
differences in sweat secretion during exercise-induced hyperthermia. Aviat. Space
Environ. Med. 77:1020-1027.
Wolf, J.E., and Maibach, H.I. (1974). Palmar eccrine sweating - the role of adrenergic and
cholinergic mediators. Brit. J. Dermatol. 91:439-446.
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