School of Kinesiology, Shanghai University of Sports, Shanghai, China.
Exercise Biological Center, China Institute of Sport Science, Beijing, China.
J Sports Sci Med. 2021 Mar 1;20(1):26-34. doi: 10.52082/jssm.2021.26. eCollection 2021 Mar.
We investigated whether single or combined methods of pre-cooling could affect high-intensity exercise performance in a hot environment. Seven male athletes were subjected to four experimental conditions for 30 min in a randomised order. The four experimental conditions were: 1) wearing a vest cooled to a temperature of 4 ℃ (Vest), 2) consuming a beverage cooled to a temperature of 4 ℃ (Beverage), 3) simultaneous usage of vest and consumption of beverage (Mix), and 4) the control trial without pre-cooling (CON). Following those experimental conditions, they exercised at a speed of 80% VOmax until exhaustion in the heat (38.1 ± 0.6 ℃, 55.3 ± 0.3% RH). Heart rate (HR), rectal temperature (T), skin temperature (T), sweat loss (SL), urine specific gravity (USG), levels of sodium (Na) and potassium (K), rating of perceived exertion (RPE), thermal sensation (TS), and levels of blood lactic acid ([Bla]) were monitored. Performance was improved using the mixed pre-cooling strategy (648.43 ± 77.53 s, p = 0.016) compared to CON (509.14 ± 54.57 s). T after pre-cooling was not different (Mix: 37.01 ± 0.27 ℃, Vest: 37.19 ± 0.33 ℃, Beverage: 37.03 ± 0.35 ℃) in all cooling conditions compared to those of CON (37.31 ±0.29 ℃). A similar T values was achieved at exhaustion in all trials (from 38.10 ℃ to 39.00 ℃). No difference in the level of USG was observed between the conditions. Our findings suggest that pre-cooling with a combination of cold vest usage and cold fluid intake can improve performance in the heat.
我们研究了单一或联合预冷方法是否会影响热环境下的高强度运动表现。7 名男性运动员以随机顺序在 4 种实验条件下进行 30 分钟的实验。四种实验条件分别为：1）穿着冷却至 4℃的背心（Vest），2）饮用冷却至 4℃的饮料（Beverage），3）同时使用背心和饮料（Mix），4）不进行预冷的对照实验（CON）。在这些实验条件下，他们以 80% VOmax 的速度在热环境中（38.1±0.6℃，55.3±0.3% RH）进行运动，直到力竭。监测心率（HR）、直肠温度（T）、皮肤温度（T）、出汗量（SL）、尿比重（USG）、钠（Na）和钾（K）水平、感知用力程度（RPE）、热感觉（TS）和血乳酸（[Bla]）水平。与 CON（509.14±54.57 s）相比，混合预冷策略（648.43±77.53 s，p=0.016）可提高运动表现。与 CON（37.31±0.29℃）相比，预冷后 T 在所有冷却条件下均无差异（Mix：37.01±0.27℃，Vest：37.19±0.33℃，Beverage：37.03±0.35℃）。在所有试验中，达到力竭时的 T 值相似（从 38.10℃到 39.00℃）。在所有条件下，USG 水平没有差异。我们的研究结果表明，使用冷背心和冷饮料联合预冷可以提高热环境下的运动表现。
