The increase in global temperatures will present a substantial challenge to human thermoregulation. Children have been purported to have a disadvantaged thermoregulatory system which may increase their vulnerability to the adverse effects of heat stress. However, limited research exists on the thermoregulatory responses of children during exercise, and most previous studies fail to account for differences in body size between participants, which can confound the interpretation of findings. This doctoral thesis aimed to provide a more comprehensive understanding of thermoregulation in children exercising under heat stress. Furthermore, this thesis aimed to investigate the effect of age, biological sex, aerobic fitness, and body composition on thermoregulation of children during exercise in the heat. Chapter three highlighted the lack of previous research that includes children of both sexes. Chapter four, five and six are experimental studies in which boys and girls aged 10-16 y, completed 45 minutes walking in warm (30°C, 40% relative humidity (RH)) and hot (40°C, 30% RH) environmental conditions. For chapter six, adult male and female participants completed the same exercise protocol to permit a direct comparison between adults and children. Our study findings suggest that biological sex does not independently influence thermoregulation of children exercising in a warm (chapter four) and hot environment (chapter five). However, a lower aerobic fitness and higher body fatness of children may increase their susceptibility to hyperthermia (chapter four and five). Lastly, children may not have a disadvantaged thermoregulatory system when compared to adults (chapter six). The collective findings from this thesis extend our understanding of thermoregulation in children during exercise under heat stress.
Thermoregulatory responses to exercise-heat stress in children and adults
Topham, T. H. (Author). 2024
Student thesis: Doctoral Thesis