Naito Takashi, Saito Tatsuya, Ohhashi Mitsunori, Hayashi Sotaro
Faculty of Law, Hokkai-Gakuen University, Sapporo, Japan.
Faculty of Medicine, Tottori University, Tottori, Japan.
Front Sports Act Living. 2023 Feb 13;5:1106882. doi: 10.3389/fspor.2023.1106882. eCollection 2023.
The study aimed to investigate the effect of body cooling with a fan-cooling jacket on body temperature responses during recovery after exercise when exposed to high solar radiation in a hot outdoor environment. Nine males cycled using ergometer until their rectal temperature increased to 38.50 °C in hot outdoor environments, followed by body cooling recovery in warm indoor environments. Subjects repeatedly performed the cycling exercise protocol, which consisted of one set of 5 min at a load of 1.5 watt/kg body weight and 15 min at a load of 2.0 watt/kg body weight at 60 rpm. Body cooling recovery consisted of cold water ingestion (10°C: CON) or cold water ingestion + wearing a fan-cooling jacket (FAN) until the rectal temperature decreased to 37.75°C. The time for the rectal temperature to reach 38.5°C did not differ between the two trials. The rate of decrease in rectal temperature at recovery tended to be higher in FAN trial than in CON trial ( = 0.082). The rate of decrease in tympanic temperature was higher in FAN trials than in CON trials ( = 0.002). The rate of decrease in mean skin temperature at the first 20 min of recovery was higher in FAN than in CON trial ( = 0.013). Body cooling recovery with a fan-cooling jacket in addition to cold water ingestion may be effective in reducing elevated tympanic and skin temperatures after exercise in the heat under a clear sky, but may be difficult to decrease rectal temperature.
该研究旨在调查在炎热的户外环境中暴露于高太阳辐射下时，使用风扇冷却夹克进行身体降温对运动恢复期间体温反应的影响。九名男性在炎热的户外环境中使用测力计进行骑行，直到他们的直肠温度升至38.50°C，随后在温暖的室内环境中进行身体降温恢复。受试者反复执行骑行运动方案，该方案包括一组在1.5瓦/千克体重负荷下进行5分钟以及在2.0瓦/千克体重负荷下以60转/分钟进行15分钟。身体降温恢复包括摄入冷水（10°C：CON组）或摄入冷水+穿着风扇冷却夹克（FAN组），直到直肠温度降至37.75°C。两次试验中直肠温度达到38.5°C的时间没有差异。在恢复过程中，FAN组直肠温度的下降速率往往高于CON组（=0.082）。FAN组鼓膜温度的下降速率高于CON组（=0.002）。在恢复的前20分钟，FAN组平均皮肤温度的下降速率高于CON组（=0.013）。在晴朗天空下的高温环境中运动后，除摄入冷水外，使用风扇冷却夹克进行身体降温恢复可能有助于降低升高的鼓膜温度和皮肤温度，但可能难以降低直肠温度。
