Why does skeletal muscle fiber contraction speed decrease during intense anaerobic exercise?

💡 Explanation

Skeletal muscle contraction speed decreases due to lactate accumulation because the increased acidity from lactate and associated ions inhibits key enzymes in glycolysis and ATP hydrolysis at the myosin head, thus disrupting cross-bridge cycling; therefore, decreased speed arises from metabolic inhibition, rather than enhanced energy supply or calcium dynamics.

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