We do not promote binge drinking. We do not binge drink. We have, however, occasionally gone beyond our own healthy drinking guidelines. It is far from a regular occurrence. When it has happened, it is almost always following a particularly long and intense workout. On the theory that “we earned the extra calories,” we allow ourselves to call for one more round.
We recently came across several new studies that forced us to rethink our behavior. It turns out that the aftermath of a killer workout is exactly the wrong time to indulge. The days when we hit the gym the hardest are days that we should be the most restrained.
Don’t take this wrong. We still believe that alcohol is fully compatible with serious athletics. In fact, in lesser quantities it may benefit recovery. The key appears to be dosage. But we are getting ahead of ourselves. We will let the research tell the story.
There is no shortage of opinions on the effects of alcohol on exercise, but surprisingly few studies have been done on the subject. This may be because it is a difficult subject to study. Alcohol tolerance and athletic performance are both highly variable and dependent on difficult to control factors such as fatigue, hydration and diet. Setting up a well structured, reproducible experiment is no easy task. There is the additional hurdle of getting approval from a university’s Clinical Research Ethics Committee to study the effects of an intoxicating substance on human subjects.
The study most often cited by people arguing that alcohol and exercise are incompatible was published in 2010 by a team of researchers from Massey University in New Zealand. It was a small study involving only 11 participants. All of the participants were men. This is far from ideal; it is too small and too lacking in diversity to be used for broad claims. Nonetheless, the experiment, which was designed to test the direct effect of alcohol on muscle recovery, is genuinely clever.
Each of the study participants was placed—sober—on a seated leg extension machine. The participants then performed 300 single leg extensions while an attached computer took detailed notes on the length, strength and speed of their repetitions. 300 repetitions of any exercise is more than enough to work a muscle to complete exhaustion. All of the participants reported major soreness the following day. Although the study fails to mention it, it is very likely that many of those participants awoke so sore that they had difficulty lowering themselves onto the toilet.
After each participant completed his exercise, he was fed either a glass of straight orange juice or a screwdriver cocktail. In theory, the juice drinkers were the control group, but we have a hard time believing that they could not tell if their drink contained alcohol. The cocktail recipe was 3.2 to 1, orange juice to vodka. This is far from a stiff drink, but it was more than sufficient for us to identify the vodka in our unscientific taste test.
The total amount of alcohol administered to each participant—excluding the control group who drank pure juice—was equal to one gram of alcohol for every kilogram of body weight. The alcohol was consumed within 90 minutes of completing the exercise. Unfortunately, the study does not detail participants’ resulting blood alcohol content. But the authors do note that “the volume of alcohol consumed . . . is enough to be considered as binge drinking.”
Over the following three days, the participants returned to the lab to do additional leg extensions. All of the participants saw a drop in the strength after doing the initial 300 repetitions. Muscles take time to recover after exercise, so an initial drop in strength was expected. The drinkers, however, lost more strength. The greatest difference was observed on the second day. The non-drinkers had lost 19% of their leg previous strength. The drinkers had lost 34%. On the bright side, it appears that the drinking delayed recovery rather than prevented it. By the third day following the exercise, both the drinkers and non-drinkers were regaining their strength at similar rates. The authors’ concluded: “alcohol magnifies the severity of skeletal muscle injury and therefore delays recovery of strength[.] . . . [P]articipants in sports containing intense eccentric muscular work should be encouraged to avoid alcohol intake in the post-event period if optimal recovery is required.”
This would seem damning for alcohol and exercise. Muscle recovery is required for building strength and no athlete wants his or her recovery affected or delayed. Fortunately, for those of us who enjoy both drinking and exercising, the story is far more complicated.
A year after the initial publication, the same group of researchers repeated their experiment, but this time they cut the amount of alcohol in half. In other words, over the 90 minutes following the exercise, the participants were served one-half gram of alcohol for every kilogram of body weight. In Steven’s case, this would amount to three beers or just over half a bottle of wine.
With the alcohol dose lowered, the results were strikingly different. There was no significant difference between the drinkers and the control group. The follow-up study concluded that the “consumption of a low dose of alcohol after damaging exercise appears to have no effect on the loss of force associated with strenuous eccentric exercise.”
Clearly alcohol can delay muscle recovery after exercise, but it appears to be dose dependent. We hope the researchers in New Zealand continue testing different alcohol levels. In the mean time, if we want more granularity on how much alcohol one can drink before affecting exercise recovery, we have to look at an earlier study done by a team at the University of Massachusetts. The alcohol dosage used in that study fell between the other two, .8 grams of alcohol for every kilogram of body weight.
There were a few key differences in the Umass study. All ten test subjects were women. Instead of using leg extensions, they used bicep curls. Blood was taken every day for five days after the exercise to track blood markers of muscle recovery rather than testing directly for loss of strength. And most importantly, they administered the alcohol before exercise. In other words, they got a bunch of ladies tipsy and dragged them into the gym.
Ten days after the initial study, the test subjects were invited back to do the same bicep curls with their opposite arm. This time they were not dosed with alcohol in advance. The results from the two sets of blood tests were compared. The researchers found no significant differences. In the words of the researchers, “The present study clearly shows that ingestion of alcohol had no effect on several indices of muscle damage after an eccentric exercise of the arm flexor muscles.”
Of all of the studies of alcohol and exercise we have seen, the one that excites us the most has yet to be published. In late 2011, Dr. Manuel Castillo from the University of Granada School of Medicine presented preliminary findings to the 11th Annual European Conference on Nutrition. His presentation, which is available online, was entitled, “BEER AFTER EXERCISE: Yes or No?” Considering that drunken tourists account for the lion’s share of Grenada’s economy, it is not surprising that Dr. Castillo’s answer was a resounding “yes.”
Dr. Castillo had 16 men run on a treadmill for 60 minutes in a room heated to 95-degrees. It was the cardio equivalent to Bikram Yoga. The goal was to make the men sweat buckets. Dr. Castillo then allowed the men rehydrate by drinking as much water as they pleased. Two weeks later, the men repeated the treadmill test, but this time each man was given 22 ounces of beer followed by as much water as he pleased.
If you have ever watched one dog inspect another at a dog park, you understand the level of scrutiny Dr. Castillo applied to his study participants. After both of the treadmill/hydration tests, each man was given a full checkup and put through a DEXA x-ray body composition scan. Blood, saliva and urine were collected. Vision and reflexes were tested. The participants were even subjected to a multiple-choice exam. Dr. Castillo did everything short of requiring a sperm sample.
Dr. Castillo did not test his samples for markers of muscle recovery. He instead looked for markers of rehydration. He wanted to know if alcohol after exercise dehydrates the drinker. His results made headlines around the world. The body scans, blood, urine, saliva and test scores all concurred. Hydration was solidly higher after drinking beer and water as opposed to plain water.
Here is what we think know about alcohol and exercise, using Steven as our example. The alcohol equivalent of six beers in the hour and a half after exercising will delay Steven’s muscle recovery by about 36 hours. Three beers over the same amount of time will have zero effect on Steven’s recovery. The equivalent of five beers consumed in only a half an hour also appears to have no affect on recovery; that said, we would never recommend this because the study subjects consumed their alcohol before exercising which is a seriously bad, stupid and dangerous idea outside of the controlled environment of a laboratory.
If Steven wants to insure that alcohol will not negatively impact his exercise recovery while taking advantage of its hydrating effects, the magic formula appears to be two drinks. Two drinks are well below the threshold affecting muscle recovery while offering the benefits of improved hydration and higher scores on some multiple-choice exams.
More and larger studies will obviously be helpful. For example, we would like to see different types of alcohol tested separately. We currently accept the US Centers for Disease Control assertion that, “It is the amount of alcohol consumed that affects a person most, not the type of alcoholic drink.” However, it may turn out that wine, beer and hard liquor have different physiological effects when it comes to exercise recovery. We hope that the teams in New Zealand and at UMASS will consider rerunning their experiments using beer or wine instead of vodka cocktails. We similarly hope that Dr. Castillo’s shirtless beer drinker will show up in a future presentation sipping on a glass of Shiraz.
All of this notwithstanding, the presently available studies are more than enough to convince us that drinking alcohol and exercising are fully compatible as long as the quantity of alcohol consumed is kept reasonable. In our own lives we have implemented the following somewhat-scientific rule:
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