Improving females' health and performance by mitigating heat strain

通过缓解热应激改善女性的健康和表现

• 批准号: MR/X036235/1
• 负责人: Jessica Mee
• 金额: $ 99.13万
• 依托单位: University of Worcester
• 依托单位国家: 英国
• 项目类别: Fellowship
• 财政年份: 2024
• 资助国家: 英国
• 起止时间: 2024 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=MR%2FX036235%2F1
• 关键词: Improving; females; health; performance; mitigating

Climate change refers to the long-term shift in global temperatures, which may occur naturally, but human activities relating to burning fossil fuels is considered a main driver. As a result, the frequency and intensity of heat waves is increasing, exposing humans to unseasonable and dangerously high temperatures which harms human health. In the UK during the five heat-periods in 2022, where temperatures exceeded 40 degree Celsius, 3,271 excess deaths were reported which is estimated to increase to over 7,000 by 2050. Furthermore, audits reveal six cases of heat illness per 100,000 in an occupational setting, two cases per 1,000 in military personnel, and nine cases per 100 in athletes. Heat illnesses are largely avoidable with the implementation of appropriate, effective, accessible, and sustainable heat mitigation strategies combined with appropriate education for more susceptible individuals.To prepare for heat stress, consensus recommendations suggest individuals should exercise in the heat, for up to 14 occasions for >60-min, where core and skin temperatures are elevated and sweating is initiated (Racinais et al., 2015). This requires relocation to a hot climate or access to an environmental chamber, which can be costly and impractical. The widespread use of air conditioning is another approach widely used to help mitigate heat strain. However, the use of air conditioning is not accessible to some of the most vulnerable, in areas of poverty, and in occupations involving outside activity. Collectively, these heat mitigation strategies increase greenhouse gas emissions contributing to global warming and increasing the risk of future extreme heat events (Lane 2021). An improved understanding and utility of techniques for mitigating heat strain that are more sustainable, accessible, time efficient, and simple to administer such as adapting using hot water immersion, and cooling using electric fans, wetting the skin and cold-water immersion, has become an urgent research priority. Males and females differ in their responses to heat stress (i.e., external heat load) largely due to females having a reduced sweating capacity, especially during periods of high heat loss requirements (i.e., during high intensity exercise). As such, females may reach dangerously high body temperatures quicker than males and consequently, have been more frequently diagnosed as heat intolerant. Hormonal fluctuations associated with the menstrual cycle modify responses to heat strain. For example, elevated progesterone concentrations during the luteal phase of the menstrual cycle (i.e., after ovulation before next period) increases resting body temperature, the onset threshold for sweating and the shift of blood to the skin surface for heat dissipation. Furthermore, perimenopausal and menopausal females experience additional heat sensitives, with the occurrence of hot flushes and night sweats which elevate their thermal discomfort. Despite known sex differences, audits reveal an under-representation of females as study participants, as such, heat mitigation guidelines, are underpinned almost exclusively by research conducted in men, without consideration of issues associated with the biological and phenotypical sex differences.The overarching aim of this proposal is to support females to navigate extreme heat episodes. We will assess more sustainable and accessible methods compared to current consensus, e.g., hot water immersion to adapt to the heat and cooling the skin to manage the heat. We will then generate bespoke female heat mitigation guidelines and distribute these to the public through available platforms to improve females' health and performance.

气候变化是指全球气温的长期变化，这种变化可能是自然发生的，但与燃烧化石燃料有关的人类活动被认为是一个主要驱动因素。因此，热浪的频率和强度正在增加，使人类暴露在不合时宜和危险的高温下，损害人类健康。在英国，在2022年的五个高温期，气温超过40摄氏度，报告了3，271例死亡，估计到2050年将增加到7，000多例。此外，审计显示，职业环境中每10万人中有6例中暑，军事人员每1,000人中有2例，运动员每100人中有9例。通过实施适当的、有效的、可获得的和可持续的热缓解策略，结合针对更易感个体的适当教育，热疾病在很大程度上是可以避免的。为了准备热应激，共识建议个人应该在高温下锻炼，最多14次，>60分钟，其中核心和皮肤温度升高，开始出汗（Racinais et al.，2015年）的报告。这需要搬迁到炎热的气候或进入环境室，这可能是昂贵和不切实际的。空调的广泛使用是另一种广泛用于帮助减轻热应变的方法。然而，在贫困地区和从事户外活动的职业中，一些最脆弱的人无法使用空调。总的来说，这些热缓解策略增加了温室气体排放，导致全球变暖，并增加了未来极端高温事件的风险（Lane 2021）。改善对用于减轻热应激的技术的理解和利用，这些技术更可持续，更容易获得，更省时，更易于管理，例如使用热水浸泡进行适应，使用电风扇进行冷却，润湿皮肤和冷水浸泡，已成为迫切的研究重点。男性和女性对热应激的反应不同（即，外部热负荷），这主要是由于女性具有降低的出汗能力，特别是在高热量损失要求期间（即，高强度运动时）。因此，女性可能比男性更快地达到危险的高体温，因此更频繁地被诊断为耐热。与月经周期相关的激素波动会改变对热应激的反应。例如，在月经周期的黄体期期间升高的孕酮浓度（即，排卵后下一个周期之前）增加静息体温、出汗的起始阈值和血液转移到皮肤表面以散热。此外，围绝经期和绝经期女性经历额外的热敏感性，出现潮热和盗汗，这加剧了她们的热不适。尽管已知的性别差异，审计显示女性作为研究参与者的代表性不足，因此，热缓解指南几乎完全由男性进行的研究支持，而不考虑与生物学和表型性别差异相关的问题。我们将评估比目前共识更可持续和更容易获得的方法，例如，热水浸泡以适应热量和冷却皮肤以管理热量。然后，我们将制定定制的女性热量缓解指南，并通过可用的平台向公众分发，以改善女性的健康和表现。