2007, Piran, Slovenia

Sweating
Figure 2: Inter-site sweat rate differences within the torso during rest and incremental
exercise in the heat. Data are means with standard errors of the means.
To obtain an integrated assessment of the differences in these local sweat rates during
exercise, data were averaged over the entire exercise duration. From these data, the rank order
(descending) of sweat rates was: lower back, upper back, shoulder, chest, abdomen and lateral
surface. However, whilst the sweat rate of the lateral regional of the torso remained
significantly lower than that observed for the upper- and lower-back regions (P>0.05),
significant differences were not observed for the other intra-torso comparisons (P>0.05).
DISCUSSION
For the torso, it is clear that the lateral regions have the lowest sweating response during
exercise-induced hyperthermia. Weiner (1945; N = 3) and Hertzman (1957; N = 5) have also
observed lower sweat secretion rates for sites located along the axillary line. Whilst the lateral
torso surface could be considered as a non-glabrous (hairy) skin surface, its sweat
responsiveness to thermal stimuli appears to be more similar to that observed in some
glabrous areas (e.g. palm, sole). It is also evident from our data that sweating is more profuse
on the back than on the abdomen. This directly conflicts with the previous observations of
Weiner (1945), which may perhaps be associated with differences in the thermal stimuli
(repeated heat exposures and intermittent exercise versus whole-body passive and incremental
exercise), measurement techniques (cotton wads pressed to the skin versus ventilated sweat
capsule technique) and sample sizes (3 versus 10).
We have previously demonstrated that the intra-regional sweat rates of the foot cannot be
assumed to be equivalent (Mekjavic et al., 2005; Taylor et al., 2006). At this conference, we
have extended this fact to the head, hand and torso. Furthermore, we have data awaiting
publication for the arms and legs (obtained using the same methods), and these data are also
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