School of Sport Exercise and Nutrition, Massey University, Palmerston North, New Zealand.
School of Sport Exercise, Nutrition, Massey University, Auckland, New Zealand.
Eur J Appl Physiol. 2022 Oct;122(10):2201-2212. doi: 10.1007/s00421-022-04996-2. Epub 2022 Jul 7.
Women remain underrepresented in the exercise thermoregulation literature despite their participation in leisure-time and occupational physical activity in heat-stressful environments continuing to increase. Here, we determined the relative contribution of the primary ovarian hormones (estrogen [E] and progesterone [P]) alongside other morphological (e.g., body mass), physiological (e.g., sweat rates), functional (e.g., aerobic fitness) and environmental (e.g., vapor pressure) factors in explaining the individual variation in core temperature responses for trained women working at very high metabolic rates, specifically peak core temperature (T) and work output (mean power output).
Thirty-six trained women (32 ± 9 year, 53 ± 9 ml·kg·min), distinguished by intra-participant (early follicular and mid-luteal phases) or inter-participant (ovulatory vs. anovulatory vs. oral contraceptive pill user) differences in their endogenous E and P concentrations, completed a self-paced 30-min cycling work trial in warm-dry (2.2 ± 0.2 kPa, 34.1 ± 0.2 °C, 41.4 ± 3.4% RH) and/or warm-humid (3.4 ± 0.1 kPa, 30.2 ± 1.2 °C, 79.8 ± 3.7% RH) conditions that yielded 115 separate trials. Stepwise linear regression was used to explain the variance of the dependent variables.
Models were able to account for 60% of the variance in T ([Formula: see text]: 41% core temperature at the start of work trial, [Formula: see text]: 15% power output, [Formula: see text]: 4% [E]) and 44% of the variance in mean power output ([Formula: see text]: 35% peak aerobic power, [Formula: see text]: 9% perceived exertion).
E contributes a small amount toward the core temperature response in trained women, whereby starting core temperature and peak aerobic power explain the greatest variance in T and work output, respectively.
尽管女性在热应激环境中参与休闲时间和职业体力活动的比例持续增加，但她们在运动体温调节文献中的代表性仍然不足。在这里，我们确定了主要卵巢激素（雌激素[E]和孕激素[P]）以及其他形态学（例如，体重）、生理学（例如，出汗率）、功能（例如，有氧健身）和环境（例如，蒸汽压）因素在解释训练有素的女性在极高代谢率下工作时核心温度反应的个体差异方面的相对贡献，具体为峰值核心温度（T）和工作输出（平均功率输出）。
36 名训练有素的女性（32±9 岁，53±9ml·kg·min），根据其内源性 E 和 P 浓度的个体差异（早期卵泡期和中期黄体期）或个体间差异（排卵与无排卵与口服避孕药使用者），完成了 30 分钟的自我调节自行车工作试验，在温暖干燥（2.2±0.2kPa，34.1±0.2°C，41.4±3.4%RH）和/或温暖潮湿（3.4±0.1kPa，30.2±1.2°C，79.8±3.7%RH）条件下，共产生 115 个单独的试验。逐步线性回归用于解释因变量的方差。
模型能够解释 T 的 60%的方差（[公式：见正文]：工作试验开始时的核心温度的 41%，[公式：见正文]：功率输出的 15%，[公式：见正文]：4%E）和平均功率输出的 44%的方差（[公式：见正文]：最大有氧功率的 35%，[公式：见正文]：感知努力的 9%）。
E 对训练有素的女性的核心温度反应贡献很小，其中起始核心温度和最大有氧能力分别解释了 T 和工作输出的最大方差。
