CORETM wearable sensor: comparison against gastrointestinal temperature during cold water ingestion and a 5 km running time-trial

Five km running time-trials (TT) are associated with rapid and significant increases in core body temperature (TC). For such races, real-time feedback from pre-exercise and exercise TC may be helpful in the design of an optimal pacing strategy aimed at limiting the possibility of developing heat-related illnesses. This study compared measurements of TC obtained with a wearable device, the CORETM, to those of a gastrointestinal pill (GI pill), during cold water ingestion and a 5 km running TT. Twelve participants (25 ± 4 yrs) ingested 7.5 mL/kg fat-free mass of 4°C water over the first 5 min of a 120 min sitting period, after which they completed a 5 km running TT at 30°C, 50% relative humidity. A TC difference > ± 0.25°C between sensors was deemed clinically unacceptable. Prior to water ingestion, the CORE-derived TC was 0.49 ± 0.25°C lower than the GI pill. The CORE was irresponsive to the 0.26 ± 0.22°C peak decline in TC captured with the GI pill 40 min following water ingestion. Prior to the TT, TC was 0.30 ± 0.25°C lower with the CORE than the GI pill. During the TT, the CORE underestimated the rate of increase in TC by 0.0125 ± 0.019°C/min compared with the GI pill, and mean absolute difference in TC between sensors was of 0.47 ± 0.34°C. In conclusion, the CORE does not capture the cooling effect of cold water ingestion and provides a clinically relevant underestimation of TC during a 5 km running TT in the heat.5公里计时跑（time-trial, TT）与核心体温（core body temperature, TC）的快速且显著升高密切相关。针对此类赛事，运动前及运动中的核心体温实时反馈，或有助于制定最优配速策略，从而降低热相关疾病的发病风险。本研究在冷水摄入与5公里计时跑过程中，对比了可穿戴设备CORETM与胃肠道测温胶囊（gastrointestinal pill, GI pill）所测得的核心体温数据。12名年龄为25±4岁的受试者，在120分钟静坐时段的前5分钟内，按照每千克无脂肪体重7.5mL的剂量摄入4℃冷水；随后在环境温度30℃、相对湿度50%的条件下完成5公里计时跑。若两台传感器的核心体温测量差值超过±0.25℃，则被认定为临床不可接受的偏差。冷水摄入前，CORETM设备测得的核心体温比GI胶囊低0.49±0.25℃。冷水摄入40分钟后，GI胶囊测得核心体温出现0.26±0.22℃的峰值下降，但CORETM设备未检测到该变化。计时跑开始前，CORETM设备测得的核心体温仍比GI胶囊低0.30±0.25℃。计时跑过程中，相较于GI胶囊，CORETM设备低估了核心体温的上升速率（差值为0.0125±0.019℃/分钟），两台传感器测得的核心体温平均绝对偏差为0.47±0.34℃。综上，CORETM设备无法检测到冷水摄入带来的降温效应，且在热环境下的5公里计时跑过程中，对核心体温存在具有临床意义的低估。