Citation

TsuzukiHayakawa K, Tochihara Y, Ohnaka T. Eur. J. Appl. Physiol. Occup. Physiol. 1995; 72(1-2): 12-17.

Copyright

(Copyright © 1995, Holtzbrinck Springer Nature Publishing Group)

DOI

10.1007/BF00964108

PMID

unavailable

Abstract

The study was conducted to investigate the thermoregulation of young children compared to that of adults. A group of 19 children (ages 9 months-4.5 years), with only 3 children aged 3 years or above, and 16 adults first rested in a thermoneutral room (air temperature 25 degrees C relative humidity 50%, air velocity 0.2 m. s(-1)). They were then exposed to a hot room (air temperature 35 degrees C, relative humidity 70%, air velocity 0.3 m. s(-1)) next door for 30 min, and then returned to the thermoneutral room where they stayed for a further 30 min. The rectal temperature (T-re), skin temperatures (T-sk) at seven sites, heart rate (HR), total sweat rate (M(sw,t)), local sweat rate (M(sw,1)) and the Na+ concentration of the sweat were measured. There was no significant difference in T-re between the children and their mothers in the rest phase. However, the T-re of the children increased as soon as they entered the hot room and was significantly higher than during the control period, and than that of the mothers during heat exposure. Mean T-sk, forehead, abdomen and instep T-sk were significantly higher in the children during both the thermoneutral and heat exposure. The M(sw,1) was significantly higher and Na+ concentrations in the sweat on the back and upperarm were significantly lower for the children during the heat exposure. They had a greater body surface area-to-mass ratio than the mothers by 64%, which indicated that they had advantages for thermal regulation, However, the sweating and T-sk responses of the children were not enough to prevent a rise in body temperature. These results would suggest that the young children had the disadvantage of heating up easily due to their smaller body sizes and there may be maturation-related differences in thermoregulation during the heat exposure between young children and mothers. KW: Hyperthermia in automobiles

Language: en