Will Having a Drink Hurt Your Performance at a Swim Meet?

It’s Saturday night at your championship meet, and you’re eating dinner with your teammates. You swam great today and would love to celebrate, but your best event’s tomorrow and you don’t want to blow it.

“And for you, sir?” your server asks.

At this, an angelic homunculus appears on one shoulder and commands, “Teetotal!” Its devil twin appears on the other shoulder and immediately counters, “Bottom’s up!”

Not too long ago, coaches and athletes alike considered drinking a good way to relax, relieve pain, and sleep soundly the night before competition. No shortage of world-class athletes, from Mickey Mantle to John Daly, were nearly as famous for their drinking as their play.

By 1982, the pendulum began swinging hard in the “alcohol bad” direction. To great fanfare, the American College of Sports Medicine issued a position stand highly critical of consumption of alcohol by athletes. Its unambiguous recommendation: To perform your best, abstain.

In the decades since, mixed and contradictory findings have added new fuel to the debate. “While abstinence may seem sensible, the impact alcohol has on recovery and sports performance is complicated and depends on many factors,” says sports researcher Matthew J. Barnes, a senior lecturer in the School of Sport, Exercise and Nutrition at Massey University in New Zealand. These factors include dose, timing, recovery interlude, and injury status.

For a 2014 Sports Medicine review, Barnes surveyed relevant studies published since the ACSM released its position paper. At least a half-dozen focused on acute effects—that is, performing while drunk, something few sports federations encourage.

For a 1986 British Journal of Sports Medicine study, healthy volunteers agreed to run different distances with blood alcohol concentrations ranging from 0.01 to 0.10. At distances of 200, 800, and 1500 meters, their times—as expected—deteriorated as they got drunker. This did not, however, prove true for the 100-meter sprint (a power event equivalent to a 25-yard swim). Amazingly, even a blood alcohol high enough for a DUI did not impair sprint performance.

A 2007 study in the European Journal of Applied Physiology reinforced this idea that intoxication hurts endurance but not strength and power. After volunteers drank an amount of alcohol based on their weight (a 150-pound person would’ve received seven 12-ounce beers), investigators tested their isometric and isokinetic strength and compared this to their sober performance. Neither measure was affected at all.

For most swimmers, of course, a more practical concern is how drinking after exercise impacts our ability to swim well the next day.

In his review, Barnes cited numerous studies detailing alcohol’s role as a physiological monkey wrench. A 2010 study in Alcohol and Alcoholism, for instance, determined alcohol’s diuretic properties impair rehydration—but only when consumed at very high levels. However, heavy drinking doesn’t seem to inhibit the replenishment of glycogen stores into skeletal muscles.

On a biochemical level, alcohol also affects factors related to immunity, anabolic hormones, and other processes key to recovery. Drinking, for instance, can impair cytokine production and interleukin expression, upsetting the normal inflammatory balance necessary for healing injuries and building strength. It also suppresses melatonin, which can degrade the quality of restorative sleep.

Many such alcohol-induced physiological changes, of course, are transient and don’t necessarily inhibit performance in the short term. This applies even to highly problematic behaviors, such as binge drinking, which epidemiologists have found afflicts athletes at much higher rates than nonathletes.

“I have a completely open mind when it comes to alcohol,” Barnes says, “but I admit I was surprised at some of the findings on binge drinking.”

Barnes was part of two studies published in the Journal of Science and Medicine in Sport, one in 2013 and one in 2014, that focused on alcohol consumption by competitive rugby players and its impact on them physically.

“I really expected that such very, very high doses would negatively impact their recovery and subsequent performance,” Barnes said. But investigators found no difference in strength, power, repeat sprint ability, and hydration status two days after what they called “heavy episodic alcohol consumption” (the participants had a mean of between 11 and 19 drinks) compared to the players’ results two days before the episode of drinking.

Not that this means binging won’t take a toll at some point. “While very high, hazardous doses of alcohol consumed after strenuous exercise may not directly impact performance in the days after exercise,” Barnes wrote, “such behavior is associated with serious long-term physical, psychological, and social harm.”

As for moderation—the recommended two-drink limit for men and one for nonpregnant women and anyone over 65—Barnes says there’s no compelling evidence this will hurt your next-day meet performance. But this assumes you actually stick to the limit.

“Moderation is simple advice and should be common sense,” Barnes says. “But when dealing with alcohol, it’s easy for common sense to be ignored.”