A weightlifter experiences muscle fatigue during a maximal lift. Which mechanism explains why lactate accumulation contributes to this phenomenon in anaerobic conditions?

💡 Explanation

Lactate accumulation reduces intracellular pH, which interferes with calcium binding to troponin, disrupting cross-bridge cycling because this binding is pH-sensitive. Therefore, force production declines due to impaired muscle contraction, rather than processes like creatine phosphate hydrolysis or action potential propagation.

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