Yoshimura Miho, Nakamura Masatoshi, Hojo Tatsuya, Arai Aya, Fukuoka Yoshiyuki
Graduate School of Health and Sports Science, Doshisha University, Kyoto, 610-0394, Japan.
Department of Physical Therapy, Faculty of Rehabilitation Studies, Nishikyushu University, Saga, 842-8585, Japan.
J Exerc Sci Fit. 2023 Jul;21(3):268-274. doi: 10.1016/j.jesf.2023.05.001. Epub 2023 May 10.
BACKGROUND/OBJECTIVE: In our previous laboratory experiment (room temperature of 25 °C), CO-rich cool-water immersion (CCWI) suppressed subjects' core body temperature even during repeated exercise. It is unclear whether the suppression of body temperature elevation would also continue after CCWI in a hot outdoor environment. Herein we investigated the thermal effects of CCWI after regular exercise training in heat on subjects' core temperature (T), three skin temperatures (T), heart rate (HR), and the rate of perceived ice (RPI).
Thirty-six subjects (25 males, 11 females) were randomly allocated into three groups (CCWI, CWI, and control). After training at their competitive clubs, each subject was immersed up to the chest in CCWI or CWI at 20 °C for 20 min, followed by a 60-min recovery period. T, T, HR, and RPI were measured at the initial rest, the end of immersion, and every 10 min during the recovery period.
Compared to the control, the CCWI subjects' T was significantly lower at 50-60 min after the end of immersion (p < 0.05). T at abdominal and lower-leg regions during the recovery period was maintained at significantly lower values in the CWI and CCWI groups versus control (p < 0.05). The CCWI subjects maintained lower T for a longer time than the CWI subjects.
These findings indicate that CCWI suppresses the rise in body temperatures more than CWI, even in a hot environment, suggesting that CCWI may be a more effective countermeasure against increasing body temperature in a hot outdoor environment.
背景/目的：在我们之前的实验室实验（室温25°C）中，即使在重复运动期间，富含一氧化碳的冷水浸泡（CCWI）也能降低受试者的核心体温。尚不清楚在炎热的户外环境中进行CCWI后，体温升高的抑制是否还会持续。在此，我们研究了在热环境中进行常规运动训练后CCWI对受试者核心温度（T）、三个皮肤温度（T）、心率（HR）和感觉凉爽程度（RPI）的热效应。
36名受试者（25名男性，11名女性）被随机分为三组（CCWI组、CWI组和对照组）。在各自的竞技俱乐部训练后，每个受试者在20°C的CCWI或CWI中浸泡至胸部20分钟，随后有60分钟的恢复期。在初始休息时、浸泡结束时以及恢复期每10分钟测量一次T、T、HR和RPI。
与对照组相比，CCWI组受试者在浸泡结束后50 - 60分钟时的T显著更低（p < 0.05）。在恢复期，CWI组和CCWI组腹部和小腿区域的T维持在显著低于对照组的值（p < 0.05）。CCWI组受试者比CWI组受试者维持较低T的时间更长。
这些发现表明，即使在炎热环境中，CCWI比CWI更能抑制体温升高，这表明CCWI可能是在炎热户外环境中对抗体温升高的更有效对策。
