Introduction The measurement of heart rate is commonly used to estimate exercise intensity. However, during endurance performance, the relationship between heart rate and oxygen consumption may be compromised by cardiovascular drift. This physiological phenomenon mainly consists of a time-dependent increase in heart rate and decrease in systolic volume and may lead to overestimate absolute exercise intensity in prediction models based on heart rate. Previous research has established that cardiovascular drift is correlated to the increase in core body temperature during prolonged exercise. Therefore, monitoring body temperature during exercise may allow to quantify the increase in heart rate attributable to cardiovascular drift and to improve the estimate of absolute exercise intensity. Monitoring core body temperature during exercise may be invasive or inappropriate, but the external auditory canal is an easily accessible alternative site for temperature measurement. Methods and analysis This study aims to assess the degree of correlation between trends in heart rate and in ear temperature during 120 min of steady-state cycling with intensity of 59% of heart rate reserve in a thermally neutral indoor environment. Ear temperature will be monitored both at the external auditory canal level with a contact probe and at the tympanic level with a professional infrared thermometer. Ethics and dissemination The study protocol was approved by an independent ethics committee. The results will be submitted for publication in academic journals and disseminated to stakeholders through summary documents and information meetings.

中文翻译：

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在长时间稳态循环期间通过耳温估计心血管漂移：一项研究方案

简介 心率测量通常用于估计运动强度。然而，在耐力表现期间，心率和耗氧量之间的关系可能会受到心血管漂移的影响。这种生理现象主要包括随时间变化的心率增加和收缩量的减少，并可能导致在基于心率的预测模型中高估绝对运动强度。先前的研究已经确定，心血管漂移与长时间运动期间核心体温的升高有关。因此，在运动期间监测体温可以量化由心血管漂移引起的心率增加，并改进对绝对运动强度的估计。在运动期间监测核心体温可能是侵入性的或不适当的，但外耳道是一个易于访问的替代温度测量位置。方法和分析 本研究旨在评估在热中性室内环境中，在 59% 的心率储备强度的 120 分钟稳态循环期间，心率趋势和耳温趋势之间的相关程度。将使用接触式探头在外耳道水平和使用专业红外温度计在鼓室水平监测耳温。伦理和传播 研究方案得到了独立伦理委员会的批准。结果将提交在学术期刊上发表，并通过摘要文件和信息会议传播给利益相关者。