A ingestão aguda de etanol reduz o W prime sem alterar a potência crítica em um teste de 3 minutos de máxima intensidade

Abstract

Acute ethanol intake modulates the production of strength, power, speed and muscular and cardiovascular resistance, impairing physical performance. In addition, it reduces exercise time in the severe intensity domain. It is possible that acute EtOH intake can modulate parameters related to the heavy (critical power) and severe (W prime) domains. The main of this study was to verify whether EtOH intake modulates critical power (PC) and W prime (W’) parameters during a 3-minute test at maximum intensity. 16 men and 8 women (31±6 years) with experience > 2 years in cycling and a low to moderate pattern of alcohol consumption participated in this study. Participants were subjected to two experimental situations, in a crossover mode, in the EtOH situation they ingested a solution containing 0.4 g/kg body weight of EtOH (vodka) diluted in artificial orange juice and in the juice situation the amount of EtOH was replaced by water. Thirty minutes after ingestion, the volunteers started the exercise protocol on the cycle ergometer at maximum intensity for 3 minutes to determine PC and W’. To compare the situations, a paired t-test was used. Data are presented as mean ± SD. The calculated PC was not different between the two experimental situations (Juice: 212.1±44.2 vs. EtOH: 211.2±44.4 W; P=0.671; dz=0.08). Although EtOH did not modulate PC, it was observed that W' was reduced by 16% in the EtOH situation compared to the control situation (Juice: 6.7±2.3 kJ vs. EtOH: 5.6±2, 5 kJ; P=0.003; dz=0.68). In addition, the average potency was 3.12% lower in the EtOH situation compared to the control situation (Juice: 258.0±48.5 W vs. EtOH: 250.0±50.8 W; P<0.001; dz = 0.85). Despite not having modulated the CP, the acute ingestion of EtOH reduced the W’, probably from the reduction of the average potency in the first half of the test. This fact suggests that EtOH can impair an athlete's ability to perform peaks above the critical power at important moments during endurance events, such as cycling.