Alcohol and Muscle Growth: Does Drinking Hurt Your Gains?

Alcohol can slow muscle growth, but the size of the effect depends on how much you drink and when. In a lab study, a heavy night of 8 to 9 drinks right after training (about 1.5 g of alcohol per kg of body weight for an 80 kg person) cut muscle protein synthesis by 24% even when protein was eaten too. One or two drinks hasn't shown a clear effect in the research so far. Regular heavy drinking is different: over years it can weaken the muscle itself.

Muscle grows when protein synthesis outpaces breakdown during the hours and days after a session. A 2014 PLOS ONE trial gave 8 active men alcohol at 1.5 g/kg after training and measured synthesis directly in muscle biopsies: it fell 24% compared with protein alone, and 37% when the alcohol came with carbohydrate instead of protein.

At 1 g/kg after damaging leg exercise, strength losses 36 hours later were bigger (about 41–45% versus 26–32%). At 0.5 g/kg, researchers found no difference. A 2019 systematic review of 12 studies concluded that alcohol after resistance training appears to lower testosterone and protein synthesis and raise cortisol, though many other recovery markers didn't change.

What does alcohol actually do to muscle growth?

Every hard session damages muscle fibres a little and switches on the machinery that rebuilds them bigger. The key process is muscle protein synthesis (MPS): cells pull amino acids from your blood and stitch them into new contractile protein. A signalling hub called mTOR tells this process to go.

Alcohol gets in the way at that switch. In the Parr et al. 2014 trial, mTOR activation two hours after exercise was higher with protein alone than in either alcohol condition, and the measured synthesis rate followed the same pattern. Synthesis still rose above resting levels in every trial, so training wasn't wasted. It just built less than it could have.

Two details from that study matter for real life:

• Protein helps but doesn't cancel it. Drinking the same amount of alcohol with 25 g of whey protein still left synthesis 24% lower than protein alone.
• The dose was large. 1.5 g/kg was described as 12 ± 2 standard drinks in the Australian measure (10 g each). That's a big team-sport celebration, not a beer with dinner.

So "alcohol kills gains" overstates it. A heavy session right after training measurably blunts the rebuild, and nobody has shown that one drink does.

How much drinking does it take to hurt your gains?

The research points to a dose threshold rather than a straight line, though the studies are small and almost all in young men.

The same New Zealand research group ran the same damaging leg workout twice. With 1 g/kg of alcohol afterwards, the exercised leg had lost about 41–45% of its strength at 36 hours, against 26–32% with a non-alcoholic drink. With half that dose, 0.5 g/kg, the two conditions were the same at every time point.

Here's what those doses mean in drinks. The table uses the US standard drink of 14 g of alcohol, which NIAAA defines as about 355 ml of 5% beer, 150 ml of 12% wine or 44 ml of 40% spirits (drinks = body weight × dose ÷ 14).

NIAAA counts binge drinking as about 4 drinks for women or 5 for men in roughly two hours. A typical binge sits close to the 1 g/kg dose where recovery measurably suffered: 5 drinks is 70 g, which works out to 0.88 g/kg at 80 kg and 1.17 g/kg at 60 kg. Smaller bodies reach each threshold with fewer drinks.

The gaps are real. There's no good evidence on the stretch between 0.5 and 1 g/kg, and very little on women, older lifters, or the cumulative effect of drinking after most sessions for months.

Will one or two drinks after the gym ruin your workout?

Probably not, based on what's been measured. At 0.5 g/kg (roughly 3 drinks for an 80 kg person) the strength-recovery study found no difference, and nothing has shown that a single beer blunts muscle building.

Timing matters. Every study above gave alcohol in the first hours after training, when the rebuild is most active.

How long after drinking can I work out, or drink after a workout?

There's no tested rule like "wait 4 hours per drink". The evidence supports something simpler:

• Put distance between hard sessions and heavy drinking. The measured effects all came from drinking in the hours after training.
• Don't train while alcohol is still in your system. Your body clears it at a fairly fixed rate, so a late night can leave you over the limit the next morning; our guide to how long alcohol stays in your system has the numbers.
• If you're going to drink, a rest day is the least costly slot. You still lose some sleep quality, but you aren't stacking alcohol on top of fresh muscle damage.

Alcohol, testosterone, sleep and hydration

Protein synthesis is the direct effect. Other routes get more attention online.

Testosterone and cortisol. The 2019 systematic review found testosterone tended to fall and cortisol tended to rise when alcohol followed resistance training. Circulating figures like "a 40% testosterone drop" don't trace back to a study we could verify, so treat them with suspicion. For what happens to hormones over weeks of not drinking, see does quitting alcohol increase testosterone.

Sleep. Muscle repairs while you sleep. A review of all known sleep studies in healthy volunteers found alcohol helps you drop off faster but fragments the second half of the night, and moderate to high doses cut total REM sleep. Researchers have proposed that sleep debt raises cortisol and lowers testosterone and IGF-1, tipping muscle toward breakdown (Dattilo et al. 2011), though that is a hypothesis, not a measured outcome in lifters. Our sleep recovery timeline covers how quickly sleep improves once you stop.

Hydration. "Alcohol dehydrates you" is less clear-cut than it sounds. In a controlled trial with 30 g of alcohol (about two drinks), wine and spirits caused a small rise in urine over 4 hours that had disappeared by 24 hours, and beer caused none. That study was in older men at a moderate dose, so for a couple of drinks, sleep matters more than fluid.

Calories. Alcohol adds energy that isn't protein, often with late food. Our alcohol calorie guide shows how fast a round adds up.

What does heavy, regular drinking do to muscle, and does it come back?

One big night is a recovery problem. Years of heavy drinking can become a muscle problem. A review in Alcohol Research: Current Reviews reports that chronic alcoholic myopathy, a slow weakening mostly of the hip and shoulder muscles, affects 40 to 60 percent of people with long-term alcohol use disorder. Alcohol interferes with both muscle building and muscle breakdown, and it reduces the ability of muscle stem cells to regenerate.

The encouraging part is how much returns. According to the same review:

• An acute episode of muscle pain and weakness after a binge usually resolves within 1 to 2 weeks without alcohol.
• Chronic myopathic changes usually resolve within 2 to 12 months of stopping.
• Up to 85 percent of people with biopsy-proven alcoholic myopathy regained measurable strength within the first year of not drinking, with full normalisation of strength by the fifth year.
• People who couldn't stop completely still improved as their total intake fell.

For a regular gym-goer who drinks most weekends, the practical gain from cutting back is fewer blunted recoveries, better sleep and more consistent training. If a third of your weekly sessions are followed by a heavy night, those are the sessions where the studies say you're leaving progress on the table.

A safety note before you stop

If you drink heavily every day, don't stop suddenly on your own. Alcohol withdrawal can cause seizures and delirium tremens. Talk to a doctor about a safe way to taper, and know the warning signs of withdrawal. Severe shaking, confusion, hallucinations or a seizure mean seek medical help immediately.

Check where your post-training drinking sits

Enter your weight, your usual drinks, when you drink and how often it follows a session. The bar shows your dose in g/kg next to the three doses researchers actually tested, so you can see whether a typical night is in the range where recovery suffered. It's an educational estimate built on small studies, not a measurement.

Frequently asked questions

Does alcohol kill your gains?

Not in small amounts, as far as research shows. About 0.5 g/kg after training (roughly 3 drinks at 80 kg) showed no extra strength loss. Heavy doses are different: 1.5 g/kg after training cut muscle protein synthesis by 24% even with protein. Drinking that much after most sessions will slow progress.

Will one beer after the gym ruin my workout?

No study has shown that one beer blunts muscle growth. The measured effects came at doses of about 6 to 9 drinks for an 80 kg person. A single drink still slightly affects sleep, so if you're chasing every bit of recovery, skip it after your hardest sessions, but it won't undo the workout.

Does eating protein cancel out alcohol?

It softens it but doesn't cancel it. In the Parr 2014 trial, alcohol taken with 25 g of whey protein lowered synthesis by 24% compared with protein alone, versus 37% when alcohol came with carbohydrate. Eating protein after training is still worth it.

How much faster will I build muscle if I quit drinking?

There's no study that gives a percentage for typical drinkers. What quitting removes is the recovery penalty after heavy nights, the sleep disruption and the extra calories. If heavy drinking regularly followed your training, expect more consistent progress; people with alcohol-related muscle weakness often regain strength within a year.

Is beer worse than spirits for muscle growth?

The alcohol is what matters, not the drink type. A 355 ml beer at 5% and a 44 ml shot at 40% each carry about 14 g of alcohol. Beer brings more fluid and carbohydrate, spirits mixed with soda bring sugar, and either one in large amounts blunts recovery the same way.

The honest takeaway

A drink or two won't wreck your training, but a heavy night straight after a session does measurably slow the rebuild, and years of heavy drinking can weaken muscle outright. The levers are simple: keep heavy drinking away from hard sessions, never train with alcohol still in your system, protect your sleep, and if you drink a lot every day, plan any change with a doctor.

If you're cutting back to train better, it helps to see the streak. Sober Tracker: Go Alcohol Free counts your alcohol-free days, lets you rate sleep and energy alongside your mood in the Reflect tab, and charts how those change in Progress. Everything is stored on your device, with no account. Get it free on the App Store or Google Play, and if you're also watching the scale, our guide to weight loss after quitting alcohol covers what to expect.

This article is for education and is not medical advice. Alcohol withdrawal can be dangerous for people who drink heavily every day, so do not stop abruptly without medical guidance. If you have a seizure, confusion, hallucinations or severe shaking, seek medical help immediately.

Sources

• Parr EB et al., Alcohol ingestion impairs maximal post-exercise rates of myofibrillar protein synthesis following a single bout of concurrent training, PLOS ONE, 2014
• Barnes MJ et al., Post-exercise alcohol ingestion exacerbates eccentric-exercise induced losses in performance, European Journal of Applied Physiology, 2010
• Barnes MJ et al., A low dose of alcohol does not impact skeletal muscle performance after exercise-induced muscle damage, European Journal of Applied Physiology, 2011
• Lakićević N, The Effects of Alcohol Consumption on Recovery Following Resistance Exercise: A Systematic Review, Journal of Functional Morphology and Kinesiology, 2019
• Simon L et al., Alcoholic Myopathy: Pathophysiologic Mechanisms and Clinical Implications, Alcohol Research: Current Reviews, 2017
• Ebrahim IO et al., Alcohol and sleep I: effects on normal sleep, Alcoholism: Clinical and Experimental Research, 2013
• Dattilo M et al., Sleep and muscle recovery: endocrinological and molecular basis for a new and promising hypothesis, Medical Hypotheses, 2011
• Polhuis KCMM et al., The Diuretic Action of Weak and Strong Alcoholic Beverages in Elderly Men: A Randomized Diet-Controlled Crossover Trial, Nutrients, 2017
• NIAAA: What Is a Standard Drink?
• NIAAA: Drinking Levels Defined