Effect of a small dose of alcohol on the endurance performance of trained cyclists.
OBJECTIVE
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.


METHODS
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.


RESULTS
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.


CONCLUSIONS
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.
Lecoultre
Virgile
V
Department of Physiology, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland. virgile.lecoultre@unil.ch
Schutz
Yves
Y
D000328:Adult; D000428:Alcohol Drinking / Q000378:metabolism / Q000523:psychology; D054874:Athletic Performance / Q000502:physiology* / Q000523:psychology; D001642:Bicycling / Q000502:physiology*; D000431:Ethanol / Q000008:administration & dosage*; D005080:Exercise Test / Q000187:drug effects / Q000379:methods / Q000523:psychology; D006801:Humans; D008297:Male; D010101:Oxygen Consumption / Q000187:drug effects / Q000502:physiology; D010807:Physical Endurance / Q000187:drug effects* / Q000502:physiology*; D055815:Young Adult
D000431:Ethanol