Can Alcohol Impair Muscle Growth and Fitness?
Does getting fit and gaining muscle mean we need to eliminate alcohol? Many of us enjoy a few drinks, especially on the weekends. The work week coming to an end is often celebrated with happy hour libation. The truth is active adults and athletes alike struggle when it comes to giving up their favorite adult beverage.
Alcohol and Fitness
Research has shown alcohol intake may cause a major setback in muscle gains and reaching fitness goals. It appears alcohol reduces muscle protein synthesis (MPS) impairing our muscle growth. Studies also show alcohol to alter hormone levels and decrease our metabolism. This means our ability to reduce body fat also becomes a problem.
There is also the issue of not being able to drink alcohol in moderation. The Dietary Guidelines recommends only one alcoholic drink per day for women and no more than two for men. Enjoying a drink has become the liquid cheat meal and reward for completing a hard workout. Unfortunately, one drink usually leads to two or more.
Research has shown some positive health benefits linked to moderate alcohol consumption. When alcohol is consumed in moderation, it’s shown to increase our good cholesterol (HDL), reduce insulin resistance and stress levels. Other studies indicate the negatives of drinking alcohol outweigh the positives. It really comes down to making the best-informed choice about alcohol consumption and your fitness goals.
Alcohol and Muscle Growth
A small study was conducted on how alcohol consumption affected muscle protein synthesis (MPS). Research participants included eight physically active men performing weight lifting and interval training as part of the testing process. They consumed whey protein and alcohol immediately after exercise and again four hours later. They also consumed a carbohydrate meal two hours after training. Muscle biopsies were taken at rest, two and eight hours following physical training.
The results showed alcohol levels elevated above baseline post exercise with both protein and carbohydrate consumption. Muscle biopsies indicated reduced rates of muscle protein synthesis (MPS) following physical training. Alcohol consumed with protein reduced MPS by 24% and 37% when combined with carbohydrate. The outcome showed a partial rescue of MPS when protein was consumed with alcohol but still a negative decrease.
Researchers concluded alcohol does impair muscle protein synthesis (MPS) despite consuming optimal nutrition. The amount of alcohol consumed was based on reported binge drinking by athletes. Because alcohol consumption could even be greater among athletes, test results could potentially provide even further decline in MPS.
The findings provide enough evidence to propose educational awareness to athletes and coaches regarding alcohol consumption and muscle recovery.
Alcohol and Fat Burning
Alcohol is shown to reduce metabolism and decrease our ability to burn fat. This is partly due to how our body responds differently to alcohol than eating real food. Our body sees alcohol as a toxin and not a nutrient so we’re unable to store alcohol calories in the same way as food calories. Instead, our metabolism shifts from burning stored food calories to removing toxic waste. The primary toxic chemicals produced from alcohol are called acetaldehyde, and acetate.
You may notice an almost immediate urge to head to the bathroom after just two drinks. Your body is temporarily using the unwanted by-products as fuel to rid itself of toxins. This slows down our natural metabolic process of adipose tissue or fat stores to be burned. According to a study published in the Journal of Clinical Investigation, alcohol replaces fat for fuel and contributes a lot of calories toward our daily requirement.
So, while we enjoy a few drinks, our metabolism is on pause for fat burning and is breaking down the booze first. The calories from any food consumed get stored as fat. Other research shows alcohol to especially decrease our ability to burn fat around the belly. We have all heard the infamous term ‘beer belly’.
Is this the end of that relaxing glass of wine before dinner? Not exactly as research has shown drinking in moderation can be beneficial to our health. According to chronic studies published in the International Journal of Obesity, older women who drank moderately showed less weight gain than women who eliminated alcohol completely. It appears these women consumed an occasional drink and on those days took in fewer calories and were physically active.
Alcohol and Hormones
Alcohol consumption is said to alter hormone levels especially testosterone. An article published in the Journal of Nutrition and Metabolism indicated high alcohol consumption (1.5 g/kg or average dose of 120g) is shown to suppress testosterone by 23%. Other research provided conflicting information stating there was no significant difference in testosterone levels after acute alcohol ingestion measured over a 16-hour period.
There appears to be inconclusive evidence on alcohol consumption and testosterone levels. However, research does indicate it would take quite a bit of alcohol to alter testosterone. Approximately nine drinks for an 180lb man would need to be consumed to lower testosterone hormone levels post exercise, according to some studies. Decreased testosterone in men can impair muscle growth, decrease sexual function, and increase the risk of osteopenia/osteoporosis.
Other research indicates high alcohol consumption stimulates the conversion of testosterone into estrogen. Plants used to produce alcoholic beverages contain phytoestrogens which can affect the male sex hormone. It appears heavy drinking increases the activity of the aromatase enzyme. This enzyme is responsible for converting the male sex hormone (testosterone) into the female sex hormone (estrogen). Increased estrogen in men can potentially cause testicular impairment and symptoms of feminization.
Does this mean men shouldn’t drink alcohol to preserve their manhood? The research so far concludes excessive or heavy drinking is what causes health problems. Drinking on occasion and in moderation (no more than two drinks for men) is shown to have no adverse effects on male reproduction or lean mass gains.
Alcohol and Eating Healthy
Drinking can lead to lowered inhibitions and mindless eating. According to an article published in the British Journal of Nutrition, alcohol consumption leads to overeating and consuming too many calories. When under the influence we are unable to put much thought into healthy eating.
Alcohol and eating go hand in hand and the outcome is typically an expanded waistline. A study on caloric intake and alcohol indicated individuals who drank wine at lunch consumed an additional 200 calories daily. The extra calories over time caused significant weight gain for most of the participants.
Be aware of how many calories you’re drinking:
- Beer (12oz) – 150 calories
- Wine (5oz) – 100 calories
- Distilled spirits (1.5oz) – 100 calories
Alcohol and Sleep
Alcohol may make us feel relaxed but is shown to adversely affect our sleep. Sleep is important for muscle recovery and tissue repair. Without adequate sleep, we’re unable to function at optimum levels.
Alcohol is a depressant and may initially help us go to sleep but staying asleep is the problem. According to research, alcohol disrupts our restorative or rapid eye movement (REM) sleep. Without REM sleep, we may experience daytime drowsiness, fatigue, and poor concentration.
The American Council on Exercise indicates alcohol adversely affects sleep patterns resulting in increased fatigue and physical stress. Without healthy reparative sleep, our athletic performance and strength are significantly affected.
Studies indicate having one or two drinks (moderate alcohol consumption) doesn’t seem to impair our sleep patterns. Disturbed sleep can occur with excessive drinking. It’s also advised not to use alcohol as a sleep aid to avoid the risk of alcohol dependency.
Alcohol and Nutrition
Alcohol contains empty calories lacking nutritional value for the body. There are seven calories per gram compared to four calories per gram found in healthy carbohydrates. Many adult beverages are blended with sugary mixers adding more unhealthy calories to the body.
Alcohol consumption is shown to impair nutrient absorption by decreasing digestive enzymes. It can also damage cells located in the digestive tract affecting nutrient absorption. Without normal digestive function, even healthy food is potentially unable to be used to benefit the body.
Studies show excessive drinking can prevent the body from absorbing adequate protein and other nutrients. We require sufficient nutrients to function at optimal fitness levels, build and maintain muscle mass.
Getting fit and gaining muscle doesn’t mean eliminating alcohol completely. It simply means making healthier choices. Building lean mass and burning fat is hard work and excellent nutrient intake is essential. Since alcohol lacks nutrient value, consuming occasionally and in moderation appears to be an acceptable option. Applying the recommended guidelines of no more than one alcoholic drink for women and two for men is shown not to adversely affect muscle growth and fitness levels. Drinking too much however is clearly not healthy for you. You may opt not to partake for optimal fitness but if you choose to consume alcohol, limiting your intake is advised.
- Evelyn B. Parr et al., Alcohol Ingestion Impairs Maximal Post-Exercise Rates of Myofibrillar Protein Synthesis following a Single Bout of Concurrent Training, PLOS one Research Article, 2014
- Louise M. Burke et al., Effect of alcohol intake on muscle glycogen storage after prolonged exercise, Journal of Applied Physiology, 2003
- Suthat Liangpunsakul, MD MPH et al., Relationship between alcohol intake, body fat, and physical activity–a population-based study, Health and Human Services Author Manuscript, 2010