What is the impact of alcohol on exercise?

Whether it’s popping a cork to toast a team win or cracking a cold one with friends after a pickup game, alcohol is often consumed by athletic individuals as a means of relaxation or celebration. Many professional athletes drink alcohol, and its use is widespread in sports.

The effects of alcohol on the body are complex, according to the National Strength and Conditioning Association (NSCA). Genetics, gender, intake, nutrition status, and body status all play a role in the metabolism and effects of alcohol. Acutely, alcohol can impact motor skills, hydration status, aerobic performance, and recovery.

Ultimately, there is no uniform effect of alcohol on athletic performance that applies to all people. Moreover, research on the effects of alcohol on exercise is limited by ethical concerns. Nevertheless, data exist on the topic. Here’s a closer look.

Drinking before exercise

Soon after drinking, alcohol boosts blood-alcohol levels, with acute effects including depression of the nervous system. Other dose-dependent effects include impaired motor skills, decreased coordination, compromised judgment, delayed reactions, and impaired balance. Not only do these effects diminish athletic performance but they also increase the risk of injury. 

According to the NSCA, the impact of moderate doses of alcohol on anaerobic performance/strength is unclear, however, no benefit appears to exist. Research has shown that even small amounts of alcohol can decrease endurance. During endurance exercise, preferred substrates for metabolism are carbohydrates and lipid; alcohol, however, supplants these substrates.

The mechanism by which alcohol affects exercise could involve the citric acid cycle, inhibition of gluconeogenesis, and increase of lactate. 

“Although alcohol may have been viewed as an ergogenic [performance-enhancing] aid in the past (likely for psychological reasons), the scientific evidence shows that alcohol hinders athletic performance, and ingestion prior to training or competition should be avoided,” wrote the NSCA. 

Intriguingly, alcohol is banned by the National Collegiate Athletic Association (NCAA) rifle competitions, and the World Anti-Doping Agency (WADA) prohibits alcohol consumption during air sports, archery, powerboating, and automobile competitions, but not for the reasons you might think—quite the opposite, it is thought to be performance-enhancing.

Drinking after exercise

Although few people drink before exercising, drinking alcohol after exercise is common. For the body to recover, it is important to trigger muscle protein synthesis, replenish glycogen stores, and rehydrate. Alcohol can interfere with all these processes.

Drinks containing 4% or more alcohol can heighten urine output and interfere with rehydration. On a related note, although beer has been promoted as a post-workout recovery beverage due to its carbohydrate and electrolyte content, it doesn’t contain nearly enough of these nutrients to compensate for energy or sweat expended during a long workout.  

The replenishment of glycogen stores is necessary after working out. It is unclear whether alcohol interferes with glycogen synthesis. Alcohol can, however, interfere with muscle protein synthesis by displacing protein substrates, thus potentially disrupting muscle growth and repair. 

“It is reasonable to conclude that the negative effects of alcohol consumption after a workout outweigh any potential beneficial effects,” wrote the NSCA. “To adequately replace lost fluids, it is important for athletes to drink rehydrating beverages such as sports drinks, or consume water with salty foods, prior to alcohol consumption. If immediate alcohol intake is inevitable, athletes should strive to only consume small volumes of alcohol.”

On the other hand, in a study published in the Journal of Strength and Conditioning Research, investigators found that with respect to short-term anaerobic performance, the immediate consumption of alcohol did not affect peak power, peak force, jump height, shuttle runs, sprint, and muscle soreness.  

In another cross-sectional, population-based study published in the European Journal of Preventive Cardiology, researchers also found that the consumption of alcohol may not be detrimental to measures of fitness. They found that moderate drinkers who drank 10 g/d of alcohol had higher peak oxygen levels compared with those who drank between 50 and 60 g/day, as well as abstainers. 

Click here to read more about alcohol’s effects on the body.