Alcohol: How Does It Affect Athletes?

Alcohol consumption is quite widespread in our society, and a large part of the population consumes, even in moderate doses, some amount of alcohol per week. This also includes athletes, especially "amateur" athletes, who often take advantage of the leisure time that sport entails to socialize with a drink in between. But what consequences can alcohol consumption have on athletes?

Effects of alcohol on athletic performance

Although in elite athletes even the smallest detail can affect the chances of success, in amateur athletes training seems to bring benefits even when they are relatively flexible with their lifestyle. Thus, various studies show that the consumption of alcohol in moderate doses does not seem to hinder training-induced improvements. For example, one study (NOTE: funded by the Beer and Health Information Center, which may induce some bias in the results) compared the benefits obtained with a 10-week program of high-intensity interval training (HIIT) in a group of athletes who consumed alcohol on a daily basis (the equivalent of two cans of beer a day if they were men, and a can if they were women) and a group that did not consume alcohol during that period.2,3 The results showed that both groups had similar benefits in body composition (decreased fat mass and increased muscle mass) and fitness (increased cardiorespiratory fitness and muscle strength), suggesting that drinking one or two beers a day does not "ruin" the benefits induced by training in amateur athletes, at least as far as physical fitness is concerned. 

However, there are also studies that suggest that alcohol consumption, especially in large doses, could worsen recovery processes and reduce adaptations to training. For example, one study found that consuming 1.5 g/kg of ethanol (which is roughly equivalent to 10 beers) reduces the rate of post-exercise protein synthesis, which would attenuate post-workout muscle regeneration.4 Similarly, another study evaluated 11 subjects who performed an exercise designed to cause muscle damage (popularly known as "soreness"), and after which they consumed 1 g/kg of ethanol (about 230 ml of vodka) or orange juice.5 The results showed that exercise resulted in a greater loss of strength during the following days if subjects consumed alcohol, confirming that excessive alcohol consumption can reduce recovery after training. It is important to mention that it has been proposed that part of these effects may be due not only to alcohol itself, but also to the fact that post-exercise alcohol consumption may prevent athletes from ingesting other nutrients of greater relevance for recovery, such as proteins. 

Beyond sports performance

Regardless of the effects (negative or not) of moderate alcohol consumption on athletic performance, it should be noted that even very low doses of alcohol can have negative effects on health. In fact, a study with data obtained worldwide and published in the prestigious journal The Lancet showed that alcohol consumption is the seventh leading cause of death in the world (accounting for between 4 and 12% of global deaths in women and men, respectively).1 In addition, the authors concluded that the only amount of alcohol that minimized adverse health effects was not drinking any alcoholic beverages per week.1 Therefore, even very low doses can have certain health consequences.

Conclusions

Although moderate alcohol consumption (e.g., one beer a day) may not affect training adaptations in amateur athletes, consuming excessive doses of alcohol does seem to interfere with recovery processes and therefore negatively affect athletic performance. In addition, regular alcohol consumption, even in low doses, can have negative effects on health. For all these reasons, alcohol consumption should be reduced as much as possible among athletes and non-athletes.

References:

1. Griswold MG, Fullman N, Hawley C, et al. Alcohol use and burden for 195 countries and territories, 1990-2016: A systematic analysis for the Global Burden of Disease Study 2016. Lancet. 2018;392(10152):1015-1035. doi:10.1016/S0140-6736(18)31310-2
2. Molina-Hidalgo C, De-Lao A, Jurado-Fasoli L, Amaro-Gahete FJ, Castillo MJ. Beer or ethanol effects on the body composition response to high-intensity interval training. The BEER-HIIT study. Nutrients. 2019;11(4). doi:10.3390/nu11040909
3. Molina-Hidalgo C, De-La-O A, Dote-Montero M, Amaro-Gahete FJ, Castillo MJ. Influence of daily beer or ethanol consumption on physical fitness in response to a high-intensity interval training program. The BEER-HIIT study. J Int Soc Sports Nutr. 2020;17(1):1-13. doi:10.1186/s12970-020-00356-7
4. Parr EB, Camera DM, Areta JL, et al. Alcohol ingestion impairs maximal post-exercise rates of myofibrillar protein synthesis following a single bout of concurrent training. PLoS One. 2014;9(2):1-9. doi:10.1371/journal.pone.0088384
5. Barnes MJ, Mündel T, Stannard SR. Acute alcohol consumption aggravates the decline in muscle performance following strenuous eccentric exercise. J Sci Med Sport. 2010;13(1):189-193. doi:10.1016/j.jsams.2008.12.627