How Alcohol can kill your Gainz

How Alcohol can kill your Gainz

Have you had a big night of drinking and noticed that your next gym session suffered majorly? And the session after that, and the next one? I’ve been there, and I wanted to find out what effects alcohol had on fitness in general. So, the following are my findings…

Alcohol, in its purest form “ethyl alcohol”, provides 7 calories per gram while protein and carbs provide 4 and fat provides 9. Unlike those macros, those 7 alcohol calories are “empty calories” – calories without nutrition (no benefit). It is also the first fuel to burn (be used as energy) and it does not get stored as glycogen. A bit of science shall we?

Around 98% of alcohol that is consumed is processed in the liver, the rest is expelled through urine, breathing, or sweat. The amount of alcohol in a standard drink will take around 10 hours for the average person to process, which means the more that is consumed at any one point, the greater the rise in blood alcohol content. For the most part, alcohol is broken down by the enzyme alcohol dehydrogenase (ADH, which is contained in the liver cells). ADH then metabolizes the alcohol into acetaldehyde. Acetaldehyde is broken down into acetate by another enzyme, aldehyde dehydrogenase. In the final stage, the acetate is further metabolized to where it eventually exits the body as carbon dioxide and water. Alcohol is absorbed rapidly from the small intestine (80%) and stomach (20%), before any other nutrients are digested. So, alcohol gets into the bloodstream and crosses the blood-brain barrier easily. It then inebriates the cerebral cortex (the part of the brain responsible for rational thought) and works its way down to the limbic system (which then takes over the role of rational thought). Because the limbic system is entirely emotional, people start to think with their emotions rather than the rational area of their brain.

Alcohol is also a depressant. Its consumption creates a demand for more GABA – a neurotransmitter responsible for restricting, or depressing the excitability of our brain (for more info and to purchase GABA, click here). Glutamate is the Neurotransmitter that has the opposite effect; it is responsible for brain excitability and can be increased through the intake of various stimulants. Over time, if a sufficient amount of alcohol is consumed, the GABA receptors become accustomed to a certain amount of alcohol and more is required to get the same depressing and intoxicating effect. In other words, tolerance occurs and with greater (chronic) use of alcohol the neurons may become entirely dependent on alcohol for its GABA function in the long term.

Testosterone is also reduced whenever alcohol is consumed! This is detrimental for athletes as testosterone is an anabolic hormone with a powerful fat loss effect. Lowered testosterone means fewer muscle gains, and less muscle means a lowered metabolic rate. A lower metabolic rate will make the job of losing fat a lot harder. This is what governs the way we use energy. Those with a higher metabolic rate will burn more calories at rest. By interfering with testosterone production, alcohol indirectly causes the body to lower its metabolic rate (and thus the rate at which it uses energy) and directly prohibits testosterone from exerting its powerful fat-burning effects.

Alcohol is particularly detrimental for athletes. It interferes with many of the processes so vital to success. Focus, performance, recovery and rebuilding are all affected. Although alcohol is absorbed rapidly, it is metabolized very slowly and its effects may still impact athletic performance up to 48 hours after the last drink.

Assuming the athlete is performing within 48 hours of its consumption, as little as two to three standard drinks can directly: Decrease strength; impair reaction time, balance and eye/hand coordination; increase fatigue – liver function is significantly impacted following the ingestion of alcohol. Up to 48 hours after the last drink the liver may still be metabolizing alcohol at the expense of glycogen (metabolized carbohydrate). Given that glycogen is vital for most of the body’s cellular functions, body fatigue, cognitive decline and loss of strength will result when it cannot be used efficiently. Reaction time, balance, coordination are also impacted by this process in addition to the direct aforementioned neurochemical effects alcohol has on the brain. Alcohol also causes dehydration, as it has an impact on kidney function, which interferes with the regulation of electrolytes and fluids in the body. The kidneys filter large amounts of water from many parts of the body, including the brain, to break down alcohol. This causes dehydration and can cripple an athlete’s performance.


  • Deplete aerobic capacity and negatively impact endurance for up to 48 hours after the last drink.
  • Impact cellular repair: Protein metabolism is negatively impacted when alcohol is in the system. This has obvious implications for muscle repair.
  • Impacts the cardiovascular system: Alcohol consumption raises blood pressure and this can result in the heart having to work harder to pump blood through the body. An abnormally fast heart beat (tachycardia) can also result from alcohol consumption. Further, alcohol increases the synthesis of cholesterol and this can increase the risk of heart disease.
  • Disrupt sleep: Alcohol significantly interferes with restful sleep. It can make falling to sleep easier to begin with due to its sedative effects but the quality of sleep (particularly rapid eye movement) will be disturbed.
  • Cause vitamin and mineral depletion: Vitamins and minerals so necessary for our health have their absorption interfered with, while the body’s own supply is slowly depleted, when alcohol is consumed. Even one or two drinks per day (supposedly the “recommended” amount) can have this effect. B vitamin, which have important enzymatic and metabolic functions are depleted extra rapidly. This deleteriously effects the heart, liver, thyroid and kidneys. Vitamin A is also depleted and this interferes with the body’s ability to fight disease. Vitamin C depletion makes one susceptible to anemia. Also, when alcohol is ingested the body excretes calcium at twice the normal rate, thus impacting on bone growth and wound healing.
  • Cause cognitive impairment: cognitive impairment (disruption of thought processes and brain damage) occur through a number of mechanisms. Alcohol related sleep disruption contributes to the insufficient restoration of one’s neural processes.
  • Lack of glucose to the brain, as a result of alcohol metabolism, causes slow, disoriented, thinking. These are just some factors. There are many more. The implications of cognitive impairment are severe for athletes: loss of motivation, focus and desire in addition to lessened perspicacity and even neuromuscular response.

With alcohol playing a huge role in celebration and social “nights out”, can people be expected to completely refrain from its use? It all depends on the individual’s goals… Most people concerned with just general maintenance can handle two or three standard drinks here and there, but if your goal is fat loss I’d advise 0 alcohol intake until you’ve reached the desired goal. The same would stand for if your goals were strength related or preparing for a competition/event.

If your friends are being evil, and forcing you to drink, what’s the best drink to go for? Stay clear from high calorie drinks like cocktails and beer! Remember that alcohol is used first, while carbs, fats and proteins take a back seat until it is all metabolised for 10 hrs or more. Low calorie drinks like wine and spirits (straight or mixed with sugar-free mixers) should be your go to drinks.


To prevent any vitamin deficiencies as the result of alcohol consumption we recommend I recommend the following supplements. For more information and purchase, please follow the links by clicking on the images below.

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