Lei Tze-Huan, Qin Qiyang, Girard Olivier, Mündel Toby, Wang Ran, Guo Li, Cao Yinhang
College of Physical Education, Hubei Normal University, Huangshi, China.
School of Athletic Performance, Shanghai University of Sport, Shanghai, 200438, China.
Eur J Appl Physiol. 2024 Feb;124(2):537-549. doi: 10.1007/s00421-023-05295-0. Epub 2023 Aug 23.
We investigated whether caffeine consumption can enhance peak oxygen uptake ([Formula: see text]) by increasing peak ventilation during an incremental cycling test, and subsequently enhance time to exhaustion (TTE) during high-intensity cycling exercise in moderate normobaric hypoxia.
We conducted a double-blind, placebo cross-over design study. Sixteen recreational male endurance athletes (age: 20 ± 2 years, [Formula: see text]: 55.6 ± 3.6 ml/kg/min, peak power output: 318 ± 40 W) underwent an incremental cycling test and a TTE test at 80% [Formula: see text] (derived from the placebo trial) in moderate normobaric hypoxia (fraction of inspired O: 15.3 ± 0.2% corresponding to a simulated altitude of ~ 2500 m) after consuming either a moderate dose of caffeine (6 mg/kg) or a placebo.
Caffeine consumption resulted in a higher peak ventilation [159 ± 21 vs. 150 ± 26 L/min; P < 0.05; effect size (ES) = 0.31]. [Formula: see text] (3.58 ± 0.44 vs. 3.47 ± 0.47 L/min; P < 0.01; ES = 0.44) and peak power output (308 ± 44 vs. 302 ± 44 W; P = 0.02, ES = 0.14) were higher following caffeine consumption than during the placebo trial. During the TTE test, caffeine consumption enhanced minute ventilation (P = 0.02; ES = 0.28) and extended the TTE (426 ± 74 vs. 358 ± 75 s; P < 0.01, ES = 0.91) compared to the placebo trial. There was a positive correlation between the percent increase of [Formula: see text] following caffeine consumption and the percent increase in TTE (r = 0.49, P < 0.05).
Moderate caffeine consumption stimulates breathing and aerobic metabolism, resulting in improved performance during incremental and high-intensity endurance exercises in moderate normobaric hypoxia.
我们研究了在递增式自行车测试中，摄入咖啡因是否能通过增加峰值通气量来提高峰值摄氧量（[公式：见正文]），并随后在中度常压缺氧的高强度自行车运动中延长力竭时间（TTE）。
我们进行了一项双盲、安慰剂交叉设计研究。16名男性业余耐力运动员（年龄：20±2岁，[公式：见正文]：55.6±3.6毫升/千克/分钟，峰值功率输出：318±40瓦）在摄入中等剂量咖啡因（6毫克/千克）或安慰剂后，于中度常压缺氧（吸入氧分数：15.3±0.2%，对应模拟海拔约2500米）条件下，进行了递增式自行车测试和在80%[公式：见正文]（源自安慰剂试验）时的TTE测试。
摄入咖啡因后峰值通气量更高[159±21与150±26升/分钟；P<0.05；效应量（ES）=0.31]。摄入咖啡因后的[公式：见正文]（3.58±0.44与3.47±0.47升/分钟；P<0.01；ES=0.44）和峰值功率输出（308±44与302±44瓦；P=0.02，ES=0.14）均高于安慰剂试验期间。在TTE测试中，与安慰剂试验相比，摄入咖啡因可提高分钟通气量（P=0.02；ES=0.28）并延长TTE（426±74与358±75秒；P<0.01，ES=0.91）。摄入咖啡因后[公式：见正文]增加的百分比与TTE增加的百分比之间存在正相关（r=0.49，P<0.05）。
中等剂量摄入咖啡因可刺激呼吸和有氧代谢，从而在中度常压缺氧的递增式和高强度耐力运动中提高运动表现。
