Rosbrook Paul, Looney David P, Margolis Lee M, Yudin Sofia Perez, Hostler David, Pryor Riana R, Pryor J Luke
Center for Research and Education in Special Environments, University at Buffalo, Buffalo, NY.
Military Performance Division, United States Army Research Institute of Environmental Medicine, Natick, MA.
Med Sci Sports Exerc. 2025 Sep 1;57(9):1947-1957. doi: 10.1249/MSS.0000000000003726. Epub 2025 Apr 18.
Studies on heat acclimation (HA) involving high-intensity exercise report impairments in time trial (TT) performance in the heat immediately after HA. This study aimed to determine whether a high-carbohydrate (HC) diet could enhance 3.22-km run TT performance in the heat following exercise-intensive short-term HA.
Fourteen healthy military-age males were assigned to either an HC diet (70% kcal carbohydrate (CHO), n = 7) or lower CHO comparison (COMP, 35% kcal CHO, n = 7) to be consumed during and for 1 wk after a 6-d HA protocol.
Baseline descriptive statistics, heat tolerance, and run performance were similar between groups ( P > 0.05). Both groups acclimated, showing reduced heart rate, rectal and skin temperature, and increased sweat rate (each P ≤ 0.03) during heat stress testing 1 and 5 d after HA. The HC group demonstrated a faster TT (959 ± 103 s vs 1067 ± 172, P = 0.02, g = 0.71) than COMP 1 d post-HA. HC showed improved TT performance from baseline at 1 d ( P = 0.01, g = 0.59) and 5 d post-HA ( P = 0.04, g = 0.59). The HC group showed greater TT improvement at 1 d (-7.0 ± 4.9% vs -0.7 ± 4.7%, P = 0.03, g = 1.23) and 5 d post-HA (-8.4 ± 4.9% vs -2.8 ± 3.9%, P = 0.01, g = 1.18), with no group differences in HA outcomes or relative strain during TT.
Insufficient CHO intake during heavy daily exertion in unacclimated heat stress, such as in short-term HA, may affect post-HA performance outcomes unless addressed with additional CHO consumption.
关于热适应（HA）与高强度运动的研究报告称，在热适应后立即进行的计时赛（TT）中，运动表现会受损。本研究旨在确定高碳水化合物（HC）饮食是否能在高强度短期热适应后的高温环境下提高3.22公里跑步计时赛的成绩。
14名健康的适龄男性被分为两组，一组采用高碳水化合物饮食（碳水化合物供能占70%千卡，n = 7），另一组为低碳水化合物对照组（COMP，碳水化合物供能占35%千卡，n = 7），在为期6天的热适应方案期间及之后1周内食用。
两组之间的基线描述性统计、耐热性和跑步表现相似（P > 0.05）。两组均实现了热适应，在热适应后第1天和第5天的热应激测试中，心率、直肠温度和皮肤温度降低，出汗率增加（各P≤0.03）。热适应后第1天，高碳水化合物组的计时赛成绩比对照组更快（959±103秒对1067±172秒，P = 0.02，g = 0.71）。高碳水化合物组在热适应后第1天（P = 0.01，g = 0.59）和第5天（P = 0.04，g = 0.59）的计时赛成绩相对于基线有所提高。高碳水化合物组在热适应后第1天（-7.0±4.9%对-0.7±4.7%，P = 0.03，g = 1.23）和第5天（-8.4±4.9%对-2.8±3.9%，P = 0.01，g = 1.18）的计时赛成绩改善更大，在热适应结果或计时赛期间的相对应变方面两组无差异。
在未适应的热应激状态下，如短期热适应期间，日常高强度运动中碳水化合物摄入不足可能会影响热适应后的运动表现结果，除非通过额外摄入碳水化合物来解决。
