Aside from the obvious effects of alcohol on our performance, there are a few other factors to consider when weighing up the cost vs. benefit as an athlete in a performance based sport.
For starters, we can look at alcohol as the ‘4th macronutrient’ because the energy value of each gram is different from carbs, fats, or protein.
1g alcohol = 7 kcal
1g fat = 9 kcal
1g carbohydrate = 4 kcal
1g protein = 4 kcal
So whilst we account for our usual macronutrients, if we’re drinking we also need to take into account the extra calories from our drinks - and the mixers alongside them!
Besides the energy balance, acute alcohol consumption, particularly in the ‘post event’ or post training/recovery period impacts a few processes.
A systematic review by Lakićević et al., (2019) summarised that whilst alcohol consumption following resistance exercise isn’t a modulating factor for creatine kinase, heart rate, lactate, blood glucose, estradiol, sexual hormone binding globulin, leukocytes and cytokines, CRP (C-reactive protein) and calcium; cortisol levels were increased whilst Testosterone and muscle protein synthesis also decreased. The same systematic review found that force, power, muscular endurance, soreness and rate of perceived exertion were also unmodified following alcohol consumption during recovery. These findings suggest that acute consumption of alcohol isn’t detrimental to recovery and strength, however, when consumed long term, recovery following resistance exercise can be impaired.
The effects of alcohol (bar the obvious sedative effects) are summarised below:
Reduced muscle protein synthesis (MPS)
Alcohol suppresses protein synthesis through the shutdown of MTOR (mechanistic target of rapamycin).
One study found that consuming alcohol with 25g of protein after training reduced protein synthesis by 24% compared to having protein by itself - you could compare this to being in a calorie deficit, which reduces MPS by approximately 36%! (Barnes et al., 2010).
Reduced growth hormone secretion & increased cortisol
Studies have found that a large dose of alcohol can reduce growth hormone (GH) pulsatile secretion from 4.7 to 3.8 and so drastically suppresses GH secretion.
Alcohol has also been shown to increase cortisol by up to 152% 4 hours after consumption (Heikkonnen et al., 1996).
Strength loss and reduced recovery capacity
In a study conducted by Barnes et al., (2009) it was shown that 6 alcoholic drinks (vodka & orange juice) caused an 11-19% strength loss compared to drinking orange juice alone.
Barnes et al., (2009) suggested that management of alcohol consumption after strenuous
eccentric exercise is as important, possibly more important, than the use of popular recovery modalities if optimal performance is the goal. E.g. don’t bother with your epsom salt baths if you’re going for a couple pints straight after training!
Alcohol inhibits long term performance and progress by impairing the normal recovery processes which occur following exercise induced microstructural damage. Impaired recovery capabilities lead to impared progression and greater likelihood of regression and overtraining.
So what are the take home messages?
Alcohol consumption is an individual choice - we aren’t here to tell you what to do, just to give you the facts so that you can make more informed choices.
The more you drink, the greater the negative impacts.
If optimal performance and recovery are your goals, be mindful of the cost vs. benefit e.g. do you value the times and memories with alcohol over not having optimal recovery and performance?
Barnes, M.J., Mündel, T. and Stannard, S.R., 2009. Post-exercise alcohol ingestion exacerbates eccentric-exercise induced losses in performance. European journal of applied physiology, 108(5), pp.1009-1014.
Barnes, M.J., Mündel, T. and Stannard, S.R., 2010. Acute alcohol consumption aggravates the decline in muscle performance following strenuous eccentric exercise. Journal of science and medicine in sport, 13(1), pp.189-193.
Heikkonen, E., Ylikahri, R., Roine, R., Välimäki, M., Härkönen, M. and Salaspuro, M., 1996. The combined effect of alcohol and physical exercise on serum testosterone, luteinizing hormone, and cortisol in males. Alcoholism: clinical and experimental research, 20(4), pp.711-716.
Lakićević, N., 2019. The effects of alcohol consumption on recovery following resistance exercise: A systematic review. Journal of functional morphology and kinesiology, 4(3), p.41.
Lang, C.H., Frost, R.A., Deshpande, N., Kumar, V., Vary, T.C., Jefferson, L.S. and Kimball, S.R., 2003. Alcohol impairs leucine-mediated phosphorylation of 4E-BP1, S6K1, eIF4G, and mTOR in skeletal muscle. American Journal of Physiology-Endocrinology and Metabolism.
Välimäki, M., Tuominen, J.A., Huhtaniemi, I. and Ylikahri, R., 1990. The pulsatile secretion of gonadotropins and growth hormone, and the biological activity of luteinizing hormone in men acutely intoxicated with ethanol. Alcoholism: Clinical and Experimental Research, 14(6), pp.928-931.