Body mapping of sweating patterns of pre-pubertal children during intermittent exercise in a warm environment

Purpose

To determine sweating responses of pre-pubertal children during intermittent exercise in a warm environment and create whole-body maps of regional sweat rate (RSRs) distribution across the body.

Methods

Thirteen pre-pubertal children; six girls and seven boys (8.1 ± 0.8 years) took part. Sweat was collected using the technical absorbent method in the last 5 min of a 30-min intermittent exercise protocol performed at 30 ℃, 40% relative humidity and 2 m·s⁻¹ frontal wind.

Results

Mean gross sweat loss (GSL) was 126 ± 47 g·m⁻²·h⁻¹ and metabolic heat production was 278 ± 50 W·m². The lower anterior torso area had the lowest RSR with a median (IQR) sweat rate (SR) of 40 (32) g·m⁻²·h⁻¹. The highest was the forehead with a median SR of 255 (163) g·m⁻²·h⁻¹. Normalised sweat maps (the ratio of each region’s SR to the mean SR for all measured pad regions) showed girls displayed lower ratio values at the anterior and posterior torso, and higher ratios at the hands, feet and forehead compared to boys. Absolute SRs were similar at hands and feet, but girls sweated less in most other areas, even after correction for metabolic rate.

Conclusion

Pre-pubertal children have different RSRs across the body, also showing sex differences in sweat distribution. Distributions differ from adults. Hands and feet RSR remain stable, but SR across other body areas increase with maturation. These data can increase specificity of models of human thermoregulation, improve the measurement accuracy of child-sized thermal manikins, and aid companies during product design and communication.