Ethanol

Is alcohol bad for your muscle building goals?

A Variety of Alcoholic Drinks

Alcohol has been consumed as beverage since prehistoric times for wide variety of uses such as religious rituals, as hygienic agent, as medicine but most often for recreational purposes. In common usage the word alcohol refers to ethanol. Ethanol, or simply drinking alcohol, provides body with about 7,1 kcal/g when ingested [1] (calories from ethanol are considered nutritionally empty). If we put this in perspective, fats provide body with about 9 kcal/g while proteins and carbohydrates provide body with 4 kcal/g each. Ethanol is one of the few nutrients that is profoundly toxic. In this article we will try to summarize available scientific literature about impact alcohol can have on your bodybuilding goals.

Impact on Muscles and Protein Synthesis

Pacy and assistants [2] were the first to confirm that chronic alcoholics have significantly lower muscle protein synthesis than non-alcoholic control subjects. Furthermore, whole body leucine oxidation was (P < 0.05) lower in chronic alcoholic compared to healthy subjects which suggests increased rate of protein degradation. Researchers also suggested that reduced muscle protein synthesis may be the lead factor for the proximal myopathy seen in such people. Clinical studies are also showing defective rates of muscle protein synthesis and whole-body protein metabolism in chronic alcohol abusers [3]. Alcohol induces changes in protein metabolism in probably all organ or tissue systems [6]. Prolonged imbalance in protein metabolism leads to reduction of lean body mass [4]. Alcohol ingestion affects all muscle groups to some extent, however, the fast-twitch type II fibers (fibers that use anaerobic metabolism to create fuel) appear to be particularly vulnerable [3-5]. Why alcohol affects mostly fast-twitch type II fibers is not know, however, same response can be observed in other catabolic states such as diabetes, fasting, sepsis, etc [7].

Another sign of chronic alcoholism is negative nitrogen balance [6]. Chronic, as well as acute alcohol consumption increases nitrogen excretion with accompanied loss of lean tissue mass [6].

Hormonal Interaction

Impact on Testosterone

It has been shown that alcohol consumption decreases both mean plasma concentration [8-16,21] and the production rate of testosterone [8] in animals as well as in normal males receiving adequate nutrition. Usually when testosterone levels are low, levels of luteinizing hormone and follicle stimulating hormone increase to stimulate testosterone secretion [9]. However, some studies [8,10] but not all [28] report lower levels of plasma luteinizing hormone and follicle stimulating hormone suggesting both a central (hypothalamus-pituitary) and gonadal (testicular) [13] effect of alcohol. Furthermore, alcohol also causes increased metabolic clearance rate of testosterone [8]. It is therefore not surprising that chronic alcohol consumption is associated with hypogandism [14,27] and gynecomastia [17,27] in male alcohol misusers. Testosterone levels also negatively correlate with duration of alcohol abuse [10]. This duration dependent decrease in serum testosterone may be due to impaired hypothalamic pituitary gonadal [8,10] and/or damaged Leydig and supporting Sertoli cells due to increased oxidative stress [10].

In vivo studies [12] are also showing that acetaldehyde (ethanal) may directly inhibit testicular production of testosterone. Acetaldehyde is derived from alcohol metabolism and besides being carcinogen [18] it also causes damage to DNA [19] and may cause abnormal muscle development as it binds to proteins [20].

Negative effects of alcohol abuse go beyond lower testosterone levels as alcohol is testicular toxin [10,11,14] and it causes testicular atrophy [14], fertility abnormalities with low sperm count and impaired sperm motility in men [10].

Impact on Growth Hormone

Alcohol consumption does not only reduce testosterone levels it also causes severe decrement in serum growth hormone [21-23]. Both hormones are known to facilitates the protein synthesis process. In one early study 0.8 g/kg of alcohol suppressed plasma growth hormone values by 70-75% [22]. Another study evaluating multiple doses (0.5 and 1.0 g/kg) of alcohol similarly found growth hormone suppression in dose-dependent manner [23].

Effects on Cortisol Levels

Cortisol levels do not seem to be significantly altered by alcohol at doses up to 0.8 g/kg [22]. Same was reported by Davis and Jeffcoate [24] where neither intravenous (1 ml/kg) nor oral (2.5 ml/kg vodka or gin) ethanol caused an increase in serum cortisol. However, studies evaluating cortisol levels in alcoholics and non-alcoholics are equivocal. It has been reported that plasma ethanol concentrations greater than 100 mg cause an increase in cortisol levels [25]. It seems that alcohol ingestion at first reduces serum cortisol levels but then causes a subsequent increase [26].

Interaction with Estrogen

Varying degrees of increased levels of estrogens are reported in alcoholic men without cirrhosis [27]. Alcoholics, consuming a minimum of 180 ml of alcohol per day, show significantly increased levels of estradiol (most potent in its estrogenic effect) [28]. Signs of excess estrogen in the body may include changes in body hair and fat distribution, gynecomastia, and increased concentrations of sex hormone binding globulin [27].

Alcohol’s Sleep Effect

A good training routine, well-regulated diet and some help from supplements are important to reach your muscle-building goals but probably the most important aspect is sleep. Sleep serves many vital functions and for bodybuilders the most important is growth. Alcohol ingestion has been shown to affect sleep, daytime alertness and physiological function during sleep [29]. It has been well documented that acute higher doses of alcohol have disruptive effects on sleep with many studies showing reduced sleep latency [29].

Are There any Benefits From Alcohol Ingestion?

Well, surprisingly there are. Moderate alcohol ingestion has been linked to cardio-protective effects in reducing mortality due to coronary artery disease [30]. Relaxation and anxiety relief have also been attributed to moderate alcohol consumption [31]. However, one should keep in mind that alcohol harmfully affects many organ systems and in some way disrupts almost all neurobiological mechanisms [29].

References

  1. Lieber, Charles S. “Perspectives: do alcohol calories count?.” The American journal of clinical nutrition 54.6 (1991): 976-982.
  2. Pacy, P. J., et al. “The effect of chronic alcohol ingestion on whole body and muscle protein synthesis—a stable isotope study.” Alcohol and Alcoholism 26.5-6 (1991): 505-513.
  3. Preedy, V. R., et al. “Chronic alcoholic myopathy: transcription and translational alterations.” The FASEB journal 8.14 (1994): 1146-1151.
  4. Martin, F., et al. “Alcoholic skeletal myopathy, a clinical and pathological study.” QJM 55.3-4 (1985): 233-251.
  5. M. E. Reilly, D. Mantle, P. J. Richardson, J. Salisbury, J. Jones, T. J. Peters & V. R. Preedy: Studies on the time-course of ethanol’s acute effects on skeletal muscle protein synthesis: comparison with acute changes in proteolytic activity. Alcoholism Clin Exp Res 21, 792-798 (1997)
  6. Preedy, Victor R., et al. “Protein metabolism in alcoholism: effects on specific tissues and the whole body.” Nutrition 15.7 (1999): 604-608.
  7. Lang, Charles H., et al. “Inhibition of muscle protein synthesis by alcohol is associated with modulation of eIF2B and eIF4E.” American Journal of Physiology-Endocrinology And Metabolism 277.2 (1999): E268-E276.
  8. Gordon, Gary G., et al. “Effect of alcohol (ethanol) administration on sex-hormone metabolism in normal men.” New England Journal of Medicine 295.15 (1976): 793-797.
  9. Cevik, Remzi, et al. “Hypothalamic-pituitary-gonadal axis hormones and cortisol in both menstrual phases of women with chronic fatigue syndrome and effect of depressive mood on these hormones.” BMC musculoskeletal disorders 5.1 (2004): 47.
  10. Maneesh, M., et al. “Alcohol abuse-duration dependent decrease in plasma testosterone and antioxidants in males.” Indian journal of physiology and pharmacology 50.3 (2006): 291.
  11. Badr, Fouad M., and Andrzej Bartke. “Effect of ethyl alcohol on plasma testosterone level in mice.” Steroids 23.6 (1974): 921-928.
  12. Badr, F. M., et al. “Suppression of testosterone production by ethyl alcohol. Possible mode of action.” Steroids 30.5 (1977): 647-655.
  13. Mendelson, Jack H., et al. “Effects of alcohol on plasma testosterone and luteinizing hormone levels.” Alcoholism: Clinical and Experimental Research 2.3 (1978): 255-258.
  14. Van Thiel, D. H., et al. “Alcohol-induced testicular atrophy. An experimental model for hypogonadism occurring in chronic alcoholic men.” Gastroenterology 69.2 (1975): 326-332.
  15. Rivier, Catherine. “Alcohol Rapidly Lowers Plasma Testosterone Levels in the Rat: Evidence that a Neural Brain‐Gonadal Pathway May Be Important for Decreased Testicular Responsiveness to Gonadotropin.” Alcoholism: Clinical and Experimental Research 23.1 (1999): 38-45.
  16. Mendelson, Jack H., et al. “Effects of acute alcohol intake on pituitary-gonadal hormones in normal human males.” Journal of Pharmacology and Experimental Therapeutics 202.3 (1977): 676-682.
  17. Cakan, Nedim, and Deepak Kamat. “Gynecomastia: evaluation and treatment recommendations for primary care providers.” Clinical pediatrics 46.6 (2007): 487-490.
  18. International Agency for Research on Cancer Monograph Working Group, Special Report: Policy A review of human carcinogens—Part E: tobacco, areca nut, alcohol, coal smoke, and salted fish. The Lancet 2009 10, 1033–1034.
  19. Norppa, Hannu, et al. “Chromosome damage induced by vinyl acetate through in vitro formation of acetaldehyde in human lymphocytes and Chinese hamster ovary cells.” Cancer research 45.10 (1985): 4816-4821.
  20. Aberle, Nicholas S., et al. “Acetaldehyde-induced cardiac contractile dysfunction may be alleviated by vitamin B1 but not by vitamins B6 or B12.” Alcohol and Alcoholism 39.5 (2004): 450-454.
  21. Tentler, J. J., et al. “Ethanol, growth hormone and testosterone in peripubertal rats.” Journal of Endocrinology 152.3 (1997): 477-487.
  22. Prinz, Patricia N., et al. “Effect of Alcohol on Sleep and Nighttime Plasma Growth Hormone and Cortisol Concentrations*.” The Journal of Clinical Endocrinology & Metabolism 51.4 (1980): 759-764.
  23. Van Cauter, E., and F. W. Turek. “Endocrine and other biological rhythms.” Endocrinology 3 (1995): 2497-2548.
  24. Davis, J. R. E., and W. J. Jeffcoate. “Lack of effect of ethanol on plasma cortisol in man.” Clinical endocrinology 19.4 (1983): 461-466.
  25. Jenkins, J. S., and J. Connolly. “Adrenocortical response to ethanol in man.” British medical journal 2.5608 (1968): 804.
  26. Linkola, Jaakko, et al. “Renin, aldosterone and cortisol during ethanol intoxication and hangover.” Acta Physiologica Scandinavica 106.1 (1979): 75-82.
  27. Boyden, Thomas W., and Richard W. Pamenter. “Effects of Ethanol on the Male Hypothalamic-Pituitary-Gonadal Axis*.” Endocrine reviews 4.4 (1983): 389-396.
  28. Muthusami, K. R., and P. Chinnaswamy. “Effect of chronic alcoholism on male fertility hormones and semen quality.” Fertility and sterility 84.4 (2005): 919-924.
  29. Roehrs, Timothy, and Thomas Roth. “Sleep, sleepiness, sleep disorders and alcohol use and abuse.” Sleep medicine reviews 5.4 (2001): 287-297.
  30. Preedy, V. R., et al. “The deleterious effects of alcohol on the heart: involvement of protein turnover.” Alcohol and Alcoholism 29.2 (1994): 141-147.

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