How Alcohol Can Effect Gym Gains

A moderate amount...

Whether it’s your CrossFit mates telling you to join their Dry January cult community or your gym bros telling you there’s no point training the day after sinking a few beers, we’ve all heard the refrain “working out after drinking just breaks down muscle.”

But how true is this piece of wisdom?

Not as true as the substantially less crowded gyms on a Sunday morning would have you believe, numerous studies seem to suggest. However, there is some truth to it, which only makes matters more complicated.

Fortunately, to help us understand what’s what, we have fitness coach Peter O’Reilly on hand to explain. Taking to Instagram late last year, the Instagram gains advisor said: “Ever wondered what the effects of drinking alcohol on muscle building is? Well here’s what the research shows.”


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Study One

“They [the scientists] looked at the effects of post exercise alcohol consumption,” Peter begins. “They trained eccentrically because they found that to induce the most muscle damage and muscle soreness. 30 min post exercise they drank 1g of per kg of bodyweight of Smirnoff Vodka (which is about 5-6 shots for an average guy).”

The result? “They found that muscle injury was magnified which therefore delayed the recovery process which could impact your performance,” Peter says.

Study Two

“In a test on mice to see how alcohol affects protein synthesis. The mice were given 3g/kg of alcohol. They injected with alcohol before their muscles were electrical stimulated. They found that alcohol consumption had a long lasting effect on protein synthesis and mTOR.”

“This implied that if you have a heavy night of drinking the night before training could limit protein synthesis which would therefore lead to limited muscular adaptations.”

Study Three

“In this study they looked at moderate alcohol consumption and hypertrophy in mice,” Peter says. “They found that although their are decrements in muscle with the use of alcohol, they were still able to make muscle size increase and had an increase of protein synthesis. This was obviously not as high as the protein synthesis that the control group provided, but very similar.”

Peter then left four important takeaways from these findings, which suggest that – although binging is never a good idea – we don’t need to rapidly remove moderate alcohol intake from our midweek diet.


  • There is a lot of evidence supporting that alcohol consumption affects protein synthesis and mTOR signalling.
  • Drinking too much alcohol the night before training will not allow you make the most out of your training session.
  • Moderately drinking after a workout won’t affect your gains too much.
  • Drinking after a workout will hurt your recovery and increase soreness.

So basically: drink one or two beers the night before a workout (if you must), but no more.

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