Research Institute for Sport and Exercise (UCRISE), University of Canberra, Bruce, Australian Capital Territory, Australia.
Faculty of Medicine and Health, Heat and Health Research Incubator, The University of Sydney, Sydney, New South Wales, Australia.
J Appl Physiol (1985). 2024 Jun 1;136(6):1440-1449. doi: 10.1152/japplphysiol.00877.2023. Epub 2024 Apr 25.
The purpose of this study was to investigate the influence of biological sex, independent of differences in aerobic fitness and body fatness, on the change in gastrointestinal temperature (ΔT) and whole body sweat rate (WBSR) of children exercising under uncompensable heat stress. Seventeen boys (means ± SD; 13.7 ± 1.3 yr) and 18 girls (13.7 ± 1.4 yr) walked for 45 min at a fixed rate of metabolic heat production per kg body mass (8 W·kg) in 40°C and 30% relative humidity. Sex and peak oxygen consumption (V̇o) were entered into a Bayesian hierarchical general additive model (HGAM) for T. Sex, V̇o, and the evaporative requirement for heat balance (E) were entered into a Bayesian hierarchical linear regression for WBSR. For 26 (12 M and 14 F) of the 35 children with measured body composition, body fat percentage was entered in a separate HGAM and hierarchical linear regression for T and WBSR, respectively. Conditional on sex-specific mean V̇o, ΔT was 1.00°C [90% credible intervals (Crl): 0.84, 1.16] for boys and 1.17°C [1.01, 1.33] for girls, with a difference of 0.17°C [-0.39, 0.06]. When sex differences in V̇o were accounted for, the difference in ΔT between boys and girls was 0.01°C [-0.25, 0.22]. The difference in WBSR between boys and girls was 0.03 L·h [-0.02, 0.07], when isolated from differences in E. The difference in ΔT between boys and girls was -0.10°C [-0.38, 0.17] when sex differences in body fat (%) were accounted for. Biological sex did not independently influence the ΔT and WBSR of children exercising under uncompensable heat stress. Limited studies have investigated the thermoregulatory responses of boys and girls exercising under uncompensable heat stress. Boys and girls often differ in physiological characteristics other than biological sex, such as aerobic fitness and body fat percentage, which may confound interpretations. We investigated the influence of biological sex on exercise thermoregulation in children, independent of differences in aerobic fitness and body fatness.
本研究旨在探讨在不可代偿性热应激下，生物学性别对儿童运动时胃肠道温度（ΔT）和全身排汗率（WBSR）变化的影响，且这种影响独立于有氧适能和体脂差异。17 名男孩（均值±标准差；13.7±1.3 岁）和 18 名女孩（13.7±1.4 岁）以每公斤体重代谢产热率（8 W·kg）固定速率在 40°C 和 30%相对湿度下行走 45 分钟。性别和最大摄氧量（V̇o）被输入到用于 T 的贝叶斯分层广义加性模型（HGAM）中。性别、V̇o 和用于热平衡的蒸发需求（E）被输入到用于 WBSR 的贝叶斯分层线性回归中。对于 35 名有体成分测量值的儿童中的 26 名（12 名男孩和 14 名女孩），体脂百分比分别被输入到用于 T 和 WBSR 的单独 HGAM 和分层线性回归中。在特定性别平均 V̇o 的条件下，男孩的ΔT 为 1.00°C [90%置信区间（Crl）：0.84，1.16]，女孩的ΔT 为 1.17°C [1.01，1.33]，差异为 0.17°C [-0.39，0.06]。当考虑到男孩和女孩之间 V̇o 的性别差异时，男孩和女孩之间的ΔT 差异为 0.01°C [-0.25，0.22]。当从 E 的差异中分离出来时，男孩和女孩之间的 WBSR 差异为 0.03 L·h [-0.02，0.07]。当考虑到体脂（%）的性别差异时，男孩和女孩之间的ΔT 差异为-0.10°C [-0.38，0.17]。在不可代偿性热应激下，生物学性别并未独立影响儿童的ΔT 和 WBSR。已有研究有限，研究了不可代偿性热应激下男孩和女孩的体温调节反应。男孩和女孩的生理特征除了生物学性别外往往存在差异，例如有氧适能和体脂百分比，这可能会混淆解释。我们研究了生物学性别对儿童运动时体温调节的影响，且这种影响独立于有氧适能和体脂差异。
