Alcohol-related myopathy is one of the earliest alcohol-associated pathological tissue changes, whether it’s acute or chronic alcohol use, it leads to change in skeletal muscle mass and function. The detrimental effects of alcohol on human physiology has been well observed affecting many aspects of metabolism, neural function, cardiovascular physiology, thermoregulation and as previously mentioned, skeletal muscle myopathy. The major skeletal muscle anabolic pathway is the mTORC1 pathway leading to muscle protein synthesis.
Firstly, alcohol inhibits Ca2+ transients into the myocyte by inhibiting Sarcolemmal Ca2+ channel actions. Alcohol decreases the expression of myosin heavy chain, a major motor protein in the thick filament, and troponin-T – which is necessary for myosin and action binding and positioning. This action impairs the excitation-contraction coupling and overall decreases strength output. The contractile and structural skeletal muscle proteins along with the extracellular matrix play a critical role in regeneration, anabolic signaling and mitochondrial functions. When exposed to ethanol, a decrease in mitochondrial fission factor dynamin-related protein 1 (DRP-1) leads into the mitochondrial unfolded protein response, which finally leads to skeletal muscle weakness. Muscles rely on protein synthesis to repair and grow after activity and injury. Disrupting its anabolic pathway and mechanisms reduces the body’s ability to rebuild muscle tissues, driving the progression of muscle loss. So, in Layman’s term, if you’re exercising using those 5 lb weights and excessive drinking, good luck getting that six-pack.
Metabolically speaking, high levels of alcohol consumption have been shown to impair hepatic gluconeogenesis and glucose output, decreasing the uptake of gluconeogenic precursors lactate and glycerol and decreases muscle glycogen uptake and storage. Neurologically, alcohol is a well-known depressant and reduces central nervous system excitability and cerebral activity. All these things detrimentally effect our bodies and overall quality of life in the long run. Think twice before you get the six-pack at the store versus the gym.
Simon, L., Bourgeois, B. L., & Molina, P. E. (2023). Alcohol and Skeletal Muscle in Health and Disease. Alcohol research : current reviews, 43(1), 04. https://doi-org.dml.regis.edu/10.35946/arcr.v43.1.04
Vella, L. D., & Cameron-Smith, D. (2010). Alcohol, athletic performance and recovery. Nutrients, 2(8), 781–789. https://doi-org.dml.regis.edu/10.3390/nu2080781
Your explanation of alcohol's effects on skeletal muscle and overall physiology is scary and thought-provoking. The disruption of the mTORC1 pathway and impaired protein synthesis helps show the detrimental impact on muscle repair and growth. The link between excessive alcohol consumption and reduced metabolic and neurological efficiency shows how far-reaching its consequences are. The comparison between a six-pack from the gym versus the store is a good way to show the importance of moderation. This information helps as a strong reminder to put health first and consider the long-term effects of our choices.
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