Centre for Exercise and Sports Science Research, School of Medical and Health Sciences, Edith Cowan University, Joondalup, Western Australia, Australia.
School of Psychology and Exercise Science, Murdoch University, Murdoch, Western, Australia, Australia.
PLoS One. 2019 Feb 27;14(2):e0212966. doi: 10.1371/journal.pone.0212966. eCollection 2019.
Two studies were conducted to examine the effects of ice slushy ingestion (ICE) and cold water immersion (CWI) on thermoregulatory and sweat responses during constant (study 1) and self-paced (study 2) exercise. In study 1, 11 men cycled at 40-50% of peak aerobic power for 60 min (33.2 ± 0.3°C, 45.9 ± 0.5% relative humidity, RH). In study 2, 11 men cycled for 60 min at perceived exertion (RPE) equivalent to 15 (33.9 ± 0.2°C and 42.5 ± 3.9%RH). In both studies, each trial was preceded by 30 min of CWI (~22°C), ICE or no cooling (CON). Rectal temperature (Tre), skin temperature (Tsk), thermal sensation, and sweat responses were measured. In study 1, ICE decreased Tre-Tsk gradient versus CON (p = 0.005) during first 5 min of exercise, while CWI increased Tre-Tsk gradient versus CON and ICE for up to 20 min during the exercise (p<0.05). In study 2, thermal sensation was lower in CWI versus CON and ICE for up to 35-40 min during the exercise (p<0.05). ICE reduced thermal sensation versus CON during the first 20 min of exercise (p<0.05). In study 2, CWI improved mean power output (MPO) by ~8 W, compared with CON only (p = 0.024). In both studies, CWI (p<0.001) and ICE (p = 0.019) delayed sweating by 1-5 min but did not change the body temperature sweating threshold, compared with CON (both p>0.05). Increased Tre-Tsk gradient by CWI improved MPO while ICE reduced Tre but did not confer any ergogenic effect. Both precooling treatments attenuated the thermal efferent signals until a specific body temperature threshold was reached.
两项研究旨在考察冰沙摄入（ICE）和冷水浸泡（CWI）对恒动（研究 1）和自定节奏（研究 2）运动期间体温调节和出汗反应的影响。在研究 1 中，11 名男性以 40-50%的峰值有氧功率骑行 60 分钟（33.2 ± 0.3°C，45.9 ± 0.5%相对湿度，RH）。在研究 2 中，11 名男性以相当于 15 级（33.9 ± 0.2°C 和 42.5 ± 3.9%RH）的感觉用力程度（RPE）骑行 60 分钟。在两项研究中，每个试验都在 30 分钟的 CWI（~22°C）、ICE 或无冷却（CON）之前进行。测量直肠温度（Tre）、皮肤温度（Tsk）、热感觉和出汗反应。在研究 1 中，与 CON 相比，ICE 在运动的前 5 分钟降低了 Tre-Tsk 梯度（p = 0.005），而 CWI 在运动期间增加了 Tre-Tsk 梯度，与 CON 和 ICE 相比长达 20 分钟（p<0.05）。在研究 2 中，与 CON 和 ICE 相比，CWI 在运动期间长达 35-40 分钟的热感觉更低（p<0.05）。与 CON 相比，ICE 在运动的前 20 分钟降低了热感觉（p<0.05）。在研究 2 中，与仅 CON 相比，CWI 提高了约 8 W 的平均功率输出（MPO）（p = 0.024）。在两项研究中，与 CON 相比，CWI（p<0.001）和 ICE（p = 0.019）都延迟了 1-5 分钟的出汗，但没有改变体温出汗阈值（两者均 p>0.05）。CWI 增加的 Tre-Tsk 梯度提高了 MPO，而 ICE 降低了 Tre，但没有带来任何有益的效果。两种预冷处理都减弱了热传出信号，直到达到特定的体温阈值。
