If an Olympic weightlifter experiences complete muscle failure during a lift, with an inability to maintain grip on the barbell, which consequence explains this failure mode?

💡 Explanation

Muscle failure during intense exercise arises due to ion imbalances that disrupt excitation-contraction coupling, causing a cessation of cross-bridge cycling. Specifically, buildup of ions impairs the sarcoplasmic reticulum's ability to regulate calcium, therefore cross-bridge formation is inhibited, rather than oxygen supply being the limiting factor.

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