Department of Sport and Exercise Science, University of Bedfordshire, Bedford, UK.
J Sports Sci. 2011 Aug;29(11):1125-34. doi: 10.1080/02640414.2011.583673. Epub 2011 Jul 21.
The aim of this study was to determine the effect of 10 days of heat acclimation with and without pre-cooling on intermittent sprint exercise performance in the heat. Eight males completed three intermittent cycling sprint protocols before and after 10 days of heat acclimation. Before acclimation, one sprint protocol was conducted in control conditions (21.8 ± 2.2°C, 42.8 ± 6.7% relative humidity) and two sprint protocols in hot, humid conditions (33.3 ± 0.6°C, 52.2 ± 6.8% relative humidity) in a randomized order. One hot, humid condition was preceded by 20 min of thigh pre-cooling with ice packs (-16.2 ± 4.5°C). After heat acclimation, the two hot, humid sprint protocols were repeated. Before heat acclimation, peak power output declined in the heat (P < 0.05) but pre-cooling prevented this. Ten days of heat acclimation reduced resting rectal temperature from 37.8 ± 0.3°C to 37.4 ± 0.3°C (P < 0.01). When acclimated, peak power output increased by ∼2% (P < 0.05, main effect) and no reductions in individual sprint peak power output were observed. Additional pre-cooling offered no further ergogenic effect. Unacclimated athletes competing in the heat should pre-cool to prevent reductions in peak power output, but heat acclimate for an increased peak power output.
本研究旨在确定 10 天热适应和不预冷对热环境中间歇性冲刺运动表现的影响。8 名男性在 10 天热适应前后完成了三个间歇性循环冲刺协议。在适应之前，一个冲刺协议在对照条件下进行（21.8±2.2°C，42.8±6.7%相对湿度），两个冲刺协议在热、湿条件下进行（33.3±0.6°C，52.2±6.8%相对湿度），顺序随机。一个热、湿条件之前，用冰袋进行 20 分钟大腿预冷（-16.2±4.5°C）。热适应后，重复两个热、湿冲刺协议。在热适应之前，峰值功率输出在热环境中下降（P<0.05），但预冷可预防这种情况。10 天热适应将静息直肠温度从 37.8±0.3°C降低至 37.4±0.3°C（P<0.01）。适应时，峰值功率输出增加约 2%（P<0.05，主要效应），并且没有观察到个体冲刺峰值功率输出的降低。额外的预冷没有提供进一步的有益效果。在热环境中比赛的未适应运动员应进行预冷以防止峰值功率输出降低，但应进行热适应以提高峰值功率输出。
