Department of Physiology, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland.
Alcohol Alcohol. 2009 May-Jun;44(3):278-83. doi: 10.1093/alcalc/agn108. Epub 2009 Jan 9.
The aim of this study was to investigate the effect of an acute small ethanol (EtOH) dose (0.5 ml EtOH/kg fat-free mass, combined with carbohydrate) in a drink on endurance performance of trained cyclists.
Thirteen well-trained male cyclists took part in this study. A 60-min cycling endurance performance test (time trial) was performed in a calorimetric chamber after drinking an EtOH (30 +/- 1.8 ml) or a non-EtOH control (C) drink.
Overall, EtOH induced a significant decrease in the average cycling power output (PO) (EtOH: 233 +/- 23 W versus C: 243 +/- 24 W, P < 0.01). The time course of mechanical PO showed an early decrease during the EtOH trial as compared to C (P < 0.01). Due to the lower PO, oxygen consumption, carbon dioxide production and glucose oxidation were significantly lower (P < 0.05) as compared to C. Relative to PO, heart rate response and ratings of perceived exertion (RPE) were increased by EtOH as compared to C (P < 0.05). In contrast, EtOH did not influence gross work efficiency, glycaemia and blood lactate concentration.
These results show that the acute low dose of EtOH decreased endurance performance. An increase of cardio-vascular strain and psychobiological mechanisms may explain this decrease of endurance performance.
本研究旨在探讨在饮料中摄入急性小剂量乙醇（0.5 毫升乙醇/公斤去脂体重，与碳水化合物结合）对训练有素的自行车运动员耐力表现的影响。
13 名训练有素的男性自行车运动员参加了这项研究。在代谢室中进行了 60 分钟的自行车耐力性能测试（计时赛），之后饮用含乙醇（30 +/- 1.8 毫升）或不含乙醇的对照（C）饮料。
总的来说，乙醇导致平均骑行功率输出（PO）显著下降（乙醇：233 +/- 23 W 与 C：243 +/- 24 W，P < 0.01）。与 C 相比，机械 PO 的时间进程在乙醇试验中表现出早期下降（P < 0.01）。由于 PO 降低，氧气消耗、二氧化碳产生和葡萄糖氧化显著降低（P < 0.05）与 C。与 PO 相比，乙醇使心率反应和感知用力评分（RPE）增加（P < 0.05）与 C。相比之下，乙醇对总工作效率、血糖和血乳酸浓度没有影响。
这些结果表明，急性低剂量乙醇降低了耐力表现。心血管紧张度和心理生物学机制的增加可能解释了耐力表现的下降。
