During intense, prolonged weightlifting, what distinguishes the effect of intracellular potassium depletion from impaired calcium release on muscle fatigue?

💡 Explanation

Muscle fatigue related to potassium depletion reduces membrane excitability. Impaired calcium release disrupts sarcomere activation within fibers; the excitation-contraction uncoupling prevents further fiber recruitment because the action potential cannot trigger calcium release. Therefore, uncoupling is the result, rather than buffered acidosis.

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