Body mapping of sweating patterns in athletes: a sex comparison

Limited regional sweat rate (RSR) data are available for females, with only a small number of sites measured across the body. Similarly, sex differences in sweating concentrate on whole body values, with limited RSR data available.

A modified absorbent technique was used to collect sweat at two exercise intensities (60% (I1) and 75% (I2) V˙O2max) in 13 aerobically trained females (21 ± 1 yr, 59.5 ± 10 mL·min·kg V˙O2max) in moderately warm conditions (25°C, 45% relative humidity, 2 m·s air velocity). Females were compared with nine aerobically trained males (23 ± 3 yr, 70.2 ± 13 mL·min·kg V˙O2max) tested under the same conditions.

Female I1 RSR was highest at the central upper back, heels, and dorsal foot and between the breasts (223, 161, 139, and 139 g·m·h, respectively). Lowest values were over the breasts and the middle and lower outer back (<16 g·m·h). At I2, the central upper back, bra triangle, and lower back showed the highest RSR (723, 470, and 333 g·m·h, respectively). Regions of the breasts and palms had the lowest RSR at I2 (<82 g·m·h). Significantly greater gross sweat loss and thus RSR were observed in males versus females at both exercise intensities. For the same metabolic heat production (male I1 vs female I2), absolute and normalized RSR showed a significant region-sex interaction (P < 0.001), with a greater distribution toward the arms and hands in females versus males.

Despite some differences in distribution, both sexes showed highest RSR on the central upper back and the lowest toward the extremities. No correlation was observed between local skin temperature and RSR, failing to explain RSR variation observed. These data have important applications for sex-specific clothing design, thermophysiological modeling, and thermal manikin design.