Blog Post

Alcohol and Muscle Growth: Does Drinking Kill Your Gains?

Strength training and alcohol

Alcohol is one of the most widely consumed recreational drugs globally. If you’re one to socialise with alcohol post-training, have a beer (and then some) to celebrate a sporting win or as part of a team bonding sesh, you’re most certainly not alone. 

It is embedded in Australian culture with studies revealing that athletes are among the biggest users of alcohol, despite the potentially harmful effects it could have on health and performance. Some simply like to call it ‘balance’. 

It’s well known that chronic high intakes of alcohol are poor for your health. So what amount of alcohol in the short-term will truly put your efforts in the gym to waste? 

Muscle Growth

Firstly, muscle growth & recovery is a process that generally occurs for up to 24-48 hours post-resistance-training. It is optimised by consuming adequate energy (calories) and high-quality protein and getting sufficient rest while following a well-structured strength or resistance training program.

Strong man flexing his muscles on a dark background

So, How Could Alcohol Impair Muscle Growth?

Theoretically, there are a lot of ways that consuming alcohol can negatively impact your potential to grow muscle, particularly if you are wanting to optimise how much muscle you can gain. 

These factors can include direct mechanisms on a physiological & biochemical level as well as more indirect factors or “flow-on” effects regarding common behaviours associated with drinking.

Bartender pouring a shot of alcohol

Decreased Muscle Protein Synthesis

A systematic review of the acute effects of alcohol on recovery following resistance exercise found that alcohol can lead to increased cortisol levels, decreased testosterone levels, decreased plasma amino acids and reduced rates of muscle protein synthesis (MPS). 

Reduced MPS is found to be influenced in a dose and time-dependent manner following resistance exercise by suppressing muscle growth signalling. Decreased MPS relates to slower recovery times, potentially impacting your strength adaptations and the quality of your subsequent training sessions.

Hormonal Effects

The dosage of alcohol and timing is further explored in a small study involving eight male participants. They fasted for 10 hours before consuming 1.5g ethanol per kg body weight. For reference, that’s 120g alcohol for an 80kg male – equivalent to 12 standard drinks!

Testosterone levels significantly decreased in all participants 10-20 hours after drinking, with this effect being more pronounced in the participants that suffered the most severe hangover. Growth hormone was also suppressed following alcohol consumption in this study. 

Since muscle growth and recovery lasts for 24-48 hours post-resistance training, reduced levels of testosterone and growth hormone may negatively impact muscle growth potential. Hence, you may want to reconsider a big night on the drinks even within a day of your strength training session.

Another study demonstrated a moderate intake of alcohol (30-40g) over a 3-week period being associated with slightly suppressed testosterone levels in men only. In comparison, smaller amounts of alcohol at 0.5g/kg in healthy women lead to a (potentially unexpected) increase in testosterone 45-90 minutes after drinking. This was found to be most prominent in women using oral contraceptives. 

Testosterone levels also increased in men on a testicular level after a low dose of alcohol (about 2-3 drinks). However, this particular increase in testosterone is likely not relevant to the process of MPS.

Groups of friends socialising with alcohol

From a broader fitness perspective, a 10-week intervention called the ‘BEER HIIT study’ looked at moderate doses of alcohol consumption of around 0.5g alcohol/kg body weight in participants undergoing a HIIT training program. It concluded that moderate and daily beer consumption does not seem to greatly affect muscular strength or other physical fitness parameters.

While these studies aren’t necessarily replicative of some of the more common lifestyles regarding alcohol intake and muscle growth, the results are still interesting to note.

Dehydration

Alcohol is a well-known diuretic that can negatively impact hydration status. Dehydration is suboptimal for muscle growth and recovery. Namely, muscle requires adequate blood flow for the delivery of sufficient oxygen and nutrients to repair and grow post-training. Since dehydration decreases blood volume, this could impair blood flow and nutrients to the muscles, theoretically creating suboptimal conditions for the process to occur.

Alcohol and Sleep 

Alcohol leads to poorer sleep quality and reduces the positive impact that physical activity has on sleep quality. Reduced sleep (length and quality) can indirectly lead to suboptimal recovery since sleep is known to be where the ‘magic’ happens regarding training adaptations and muscle growth. 

Tired woman pressing the snooze alarm on the bed side table

“Alcohol Made Me Do It” 

Alcohol not only influences your choice of whether to drunk text your ex or not… it can also influence your food choices, resulting in less-than-optimal choices that aren’t exactly supportive of muscle growth. Alcohol can greatly impact your nutrition and lifestyle choices in the following days when most of the muscle growth adaptations from training occur.

Let’s say, you’ve just finished a Saturday morning gym sesh with your mates and decide to go out for a different kind of ‘sesh’ afterwards… In the next 12 hours post-training your only intake is pizza, chips and alcohol, likely adding up to a very low protein intake.

Add in a high intake of energy from saturated fats and carbohydrates, which can lead to excess consumption of total daily calories on top of becoming dehydrated and sleeping poorly that night… That sounds like a recipe for suboptimal muscle growth and recovery to me!

a large array of deep-fried fast-food

You might question, “What if I still consume adequate protein post-training while drinking alcohol?”

A study investigated just that… with eight physically active males displaying reduced rates of MPS with alcohol consumption and concurrent exercise, even when co-ingested with protein. The control group (without protein) had a 37% reduction in MPS, whereas the group that consumed protein with alcohol still had a 24% reduction in MPS.

Ultimately, alcohol was found to suppress the anabolic response, which could consequently impair recovery and adaptation to training. 

Graph displaying measures of muscle protein synthesis comparing alcohol and carbohydrate group versus alcohol and protein group

Figure from the above-mentioned study: ‘Myofibrillar fractional synthetic rate (FSR) throughout 2-8h recovery following a single bout of concurrent training’ – which is a common measure of protein synthesis.

Summary

From the research, we can see that the impact of alcohol on sporting performance and recovery is dependent on factors such as the timing of alcohol intake post-exercise and the amount of alcohol consumed.

It appears that a few drinks after training won’t completely write off your strength session or make your efforts in the gym completely redundant.… 

Man deadlifting at a CrossFit gym

Considerations such as the timing of drinking post-training and the amount of alcohol ingested do matter though.

It’s always a good idea to take into account other nutrition & lifestyle choices that you make around alcohol as those could be adding extra obstacles to your muscle growth goals.

By Monica Cvoro

Monica is a supportive dietitian that has a passion for performance-focused nutrition. She enjoys strength & conditioning training and CrossFit. While performance focused nutrition is a strong interest of hers, Monica also loves helping people improve their relationship with food by encouraging people to nourish their bodies with nutritious & delicious food. Qualifications: Bachelor of Science (Nutrition & Metabolism) Masters of Nutrition & Dietetics

Alcohol and Muscle Growth: Does Drinking Kill My Gains?

Alcohol is one of the most widely consumed recreational drugs globally. If you’re one to socialise with alcohol post-training, have a beer (and then some) to celebrate a sporting win or as part of a team bonding sesh, you’re most certainly not alone. 

It is embedded in Australian culture with studies revealing that athletes are among the biggest users of alcohol, despite the potentially harmful effects it could have on health and performance. Some simply like to call it ‘balance’. 

It’s well known that chronic high intakes of alcohol are poor for your health. So what amount of alcohol in the short-term will truly put your efforts in the gym to waste? 

Muscle Growth

Firstly, muscle growth & recovery is a process that generally occurs for up to 24-48 hours post-resistance-training. It is optimised by consuming adequate energy (calories) and high-quality protein as well as getting sufficient rest, while following a well-structured strength or resistance training program.

So, How Could Alcohol Impair Muscle Growth?

Theoretically, there are a lot of ways that consuming alcohol can negatively impact your potential to grow muscle, particularly if you are wanting to optimise how much muscle you can gain. 

These factors can include direct mechanisms on a physiological & biochemical level as well as more indirect factors or “flow-on” effects regarding common behaviours associated with drinking.

Decreased Muscle Protein Synthesis

A systematic review of the acute effects of alcohol on recovery following resistance exercise found that alcohol can lead to increased cortisol levels, decreased testosterone levels, decreased plasma amino acids and reduced rates of muscle protein synthesis (MPS). 

Reduced MPS is found to be influenced in a dose-and time-dependent manner following resistance exercise by suppressing muscle growth signalling. Decreased MPS relates to slower recovery times, potentially impacting your strength adaptations and the quality of your subsequent training sessions.

Hormonal Effects

The dosage of alcohol and timing is further explored in a small study involving eight male participants. They fasted for 10 hours before consuming 1.5g ethanol per kg body weight. For reference, that’s 120g alcohol for an 80kg male – equivalent to 12 standard drinks!

Testosterone levels significantly decreased in all participants 10-20 hours after drinking, with this effect being more pronounced in the participants that suffered the most severe hangover. Growth hormone was also suppressed following alcohol consumption in this study. 

Since muscle growth and recovery lasts for 24-48 hours post-resistance training, reduced levels of testosterone and growth hormone may negatively impact muscle growth potential. Hence, you may want to reconsider a big night on the drinks even within a day of your strength training session.

Another study, demonstrated a moderate intake of alcohol (30-40g) over a 3-week period being associated with slightly suppressed testosterone levels in men only. In comparison, smaller amounts of alcohol at 0.5g/kg in healthy women lead to a (potentially unexpected) increase in testosterone 45-90 minutes after drinking. This was found to be most prominent in women using oral contraceptives. 

Testosterone levels also increased in men on a testicular level after a low dose of alcohol (about 2-3 drinks). However, this particular increase in testosterone is likely not relevant to the process of MPS.

From a broader fitness perspective, a 10-week intervention called the ‘BEER HIIT study’ looked at moderate doses of alcohol consumption of around 0.5g alcohol/kg body weight in participants undergoing a HIIT training program. It concluded that a moderate and daily beer consumption does not seem to greatly affect muscular strength or other physical fitness parameters.

While these studies aren’t necessarily replicative of some of the more common lifestyles regarding alcohol intake and muscle growth, the results are still interesting to note.

Dehydration

Alcohol is a well-known diuretic that can negatively impact hydration status. Dehydration is suboptimal for muscle growth and recovery. Namely, muscle requires adequate blood flow for the delivery of sufficient oxygen and nutrients to repair and grow post-training. Since dehydration decreases blood volume, this could impair blood flow and nutrients to the muscles, theoretically creating suboptimal conditions for the process to occur.

Alcohol and Sleep 

Alcohol leads to poorer sleep quality and reduces the positive impact that physical activity has on sleep quality. Reduced sleep (length and quality) can indirectly lead to suboptimal recovery, since sleep is known to be where the ‘magic’ happens regarding training adaptations and muscle growth. 

“Alcohol Made Me Do It” 

Alcohol not only influences your choice of whether to drunk text your ex or not… it can also influence your food choices, resulting in less-than-optimal choices that aren’t exactly supportive of muscle growth. Alcohol can greatly impact your nutrition and lifestyle choices in the following days, when most of the muscle growth adaptations from training occur.

Let’s say, you’ve just finished a Saturday morning gym sesh with your mates and decide to go out for a different kind of ‘sesh’ afterwards… In the next 12 hours post-training your only intake is pizza, chips and alcohol, likely adding up to a very low protein intake.

Add in a high intake of energy from saturated fats and carbohydrates, which can lead to excess consumption of total daily calories on top of becoming dehydrated and sleeping poorly that night… That sounds like a recipe for suboptimal muscle growth and recovery to me!

You might question, “What if I still consume adequate protein post-training while drinking alcohol?”

A study investigated just that… with eight physically active males displaying reduced rates of MPS with alcohol consumption and concurrent exercise, even when co-ingested with protein. The control group (without protein) had a 37% reduction in MPS, whereas the group that consumed protein with alcohol still had a 24% reduction in MPS.

Ultimately, alcohol was found to suppress the anabolic response, which could consequently impair recovery and adaptation to training. 

Figure from the above-mentioned study: ‘Myofibrillar fractional synthetic rate (FSR) throughout 2-8h recovery following a single bout of concurrent training’ – which is a common measure of protein synthesis.

Summary

From the research, we can see that the impact of alcohol on sporting performance and recovery is dependent on factors such as the timing of alcohol intake post-exercise and the amount of alcohol consumed.

It appears that a few drinks after training won’t completely write off your strength session or make your efforts in the gym completely redundant.… 

Considerations such as the timing of drinking post-training and the amount of alcohol ingested do matter though.

It’s always a good idea to take into account other nutrition & lifestyle choices that you make around alcohol as those could be adding extra obstacles to your muscle growth goals.

By Monica Cvoro

Monica is a supportive dietitian that has a passion for performance-focused nutrition. She enjoys strength & conditioning training and CrossFit. While performance focused nutrition is a strong interest of hers, Monica also loves helping people improve their relationship with food by encouraging people to nourish their bodies with nutritious & delicious food. Qualifications: Bachelor of Science (Nutrition & Metabolism) Masters of Nutrition & Dietetics