Circadian Timing and Heat Stress in Firefighters

Title & Dataset supporting: Circadian modulation of core temperature and thermoregulatory strain during live-fire compartment exposure in firefighters Mauvieux B., Markov A., Besnard S., Touitou Y., Edwards B.J. (2025) Description : This dataset accompanies the manuscript submitted to the Journal of Thermal Biology. It contains anonymized physiological and environmental data recorded during standardized live-fire compartment training conducted at two circadian phases: late morning (09:00 h) and late evening (21:30 h). Twenty-one male professional firefighters completed both sessions on the same day under matched thermal loads. The dataset allows replication of all analyses described in the paper, including core-temperature kinetics, cardiovascular and perceptual strain, hydration indices, and environmental thermal gradients. Data content - The repository includes the following files: Tcore_AM_PM.csv (Continuous core temperature (°C) recorded via ingestible e-Celsius® sensors) Variables: Subject_ID, Condition (AM/PM), Time_min, Tcore_C. HR_RPE_BW.csv Heart-rate data, Borg RPE, body mass and total body water pre/post exposure. Variables: Subject_ID, Condition, HR_mean, HR_max, RPE, BodyMass_pre, BodyMass_post, TBW_pre, TBW_post. Skin_Microclimate.csv Chest and neck skin temperature (°C) and under-PPE humidity (%RH). Variables: Subject_ID, Condition, Tskin_chest, Tskin_neck, Temp_underPPE, RH_underPPE. Environment_Thermocouples.csv Air-temperature recordings (°C) from vertical thermocouple trees at five heights (0.10–2.30 m). Variables: Session_ID, Condition, Height_m, Time_min, Temp_C. Summary_Table1.xlsx Summary statistics (mean ± SD) for all physiological variables, matching Table 1 of the manuscript. Metadata_StudyDesign.pdf Overview of study design, measurement devices, calibration details, and analysis workflow (R v4.x; lme4, afex, emmeans). Units All temperatures are in degrees Celsius (°C). Heart rate: beats per minute (bpm). Body mass: kilograms (kg). Total body water: percentage of body mass (%). Humidity: relative humidity (%RH). Time: minutes relative to exposure start (T = 0 min). Ethics and confidentiality : All participants provided written informed consent. Data are pseudonymized (Subject IDs = random numeric codes) and comply with the GDPR MR-004 framework (CNIL, France). Licensing : This dataset is released under the Creative Commons Attribution 4.0 International (CC BY 4.0) licence, permitting reuse with proper citation. Citation - If you use these data, please cite: Mauvieux B., Markov A., Besnard S., Touitou Y., Edwards B.J. (2025). Circadian modulation of core temperature and thermoregulatory strain during live-fire compartment exposure in firefighters. Dataset available at Mendeley Data . Contact For questions or additional data access, please contact: Benoit Mauvieux – Normandie Univ., UNICAEN, UR 7480 VERTEX, Caen, France Email: [e-mail] ORCID: 0000-0003-4862-6531标题与配套数据集：消防人员实战火灾舱室暴露期间核心体温（core temperature）与体温调节负荷（thermoregulatory strain）的昼夜节律调控 Mauvieux B., Markov A., Besnard S., Touitou Y., Edwards B.J. (2025) 描述：本数据集配套投稿至《热生物学杂志》（Journal of Thermal Biology）的研究手稿。数据集包含于两个昼夜时段——上午晚些时候（09:00）与傍晚晚些时候（21:30）开展的标准化实战火灾舱室训练期间记录的匿名化生理与环境数据。 21名男性职业消防员于同日、在匹配的热负荷条件下完成了两次训练实验。本数据集可复现论文中描述的全部分析内容，涵盖核心体温动力学、心血管与感知负荷、水合状态指标以及环境热梯度。 数据内容：本数据集仓库包含以下文件： Tcore_AM_PM.csv：通过可摄入式e-Celsius®传感器记录的连续核心体温（单位：℃）。变量包含：Subject_ID（受试者编号）、Condition（实验时段，AM/PM）、Time_min（以暴露开始时刻为T=0的分钟数）、Tcore_C（核心体温，单位：℃）。 HR_RPE_BW.csv：心率、伯格自觉劳累分级（Borg RPE）、体质量与总体水的暴露前后数据。变量包含：Subject_ID、Condition、HR_mean（平均心率）、HR_max（最大心率）、RPE（伯格自觉劳累分级得分）、BodyMass_pre（暴露前体质量）、BodyMass_post（暴露后体质量）、TBW_pre（暴露前总体水）、TBW_post（暴露后总体水）。 Skin_Microclimate.csv：胸部与颈部皮肤温度（单位：℃）以及个人防护装备（Personal Protective Equipment, PPE）下的相对湿度（%RH）。变量包含：Subject_ID、Condition、Tskin_chest（胸部皮肤温度）、Tskin_neck（颈部皮肤温度）、Temp_underPPE（PPE下空气温度）、RH_underPPE（PPE下相对湿度）。 Environment_Thermocouples.csv：5个高度（0.10–2.30 m）的垂直热电偶阵列采集的空气温度数据（单位：℃）。变量包含：Session_ID、Condition、Height_m（高度，单位：m）、Time_min（以暴露开始时刻为T=0的分钟数）、Temp_C（空气温度，单位：℃）。 Summary_Table1.xlsx：所有生理变量的汇总统计量（均值±标准差），与论文表1内容完全一致。 Metadata_StudyDesign.pdf：研究设计概述、测量设备、校准细节以及分析流程（使用R v4.x版本，调用lme4、afex、emmeans软件包）。 单位说明：所有温度单位均为摄氏度（℃）；心率单位为次/分钟（bpm）；体质量单位为千克（kg）；总体水为体质量占比（%）；湿度为相对湿度（%RH）；时间为相对于暴露开始时刻的分钟数（T=0 min）。 伦理与保密：所有受试者均签署了书面知情同意书。数据采用伪匿名化处理（Subject_ID为随机数字编码），符合法国国家信息与自由委员会（Commission nationale de l'informatique et des libertés, CNIL）制定的通用数据保护条例（General Data Protection Regulation, GDPR）MR-004框架要求。 授权许可：本数据集采用知识共享署名4.0国际版（Creative Commons Attribution 4.0 International, CC BY 4.0）许可协议发布，允许在恰当引用的前提下进行复用。 引用说明：若使用本数据集，请引用如下文献： Mauvieux B., Markov A., Besnard S., Touitou Y., Edwards B.J. (2025). Circadian modulation of core temperature and thermoregulatory strain during live-fire compartment exposure in firefighters. Dataset available at Mendeley Data 联系方式：若有疑问或需额外数据访问权限，请联系： Benoit Mauvieux – Normandie Univ., UNICAEN, UR 7480 VERTEX, Caen, France 邮箱：[e-mail] ORCID: 0000-0003-4862-6531