During intense exercise, muscle fatigue can limit performance. If ATP hydrolysis rates greatly exceed ATP production within a muscle fiber, which failure becomes increasingly likely?

💡 Explanation

If ATP hydrolysis exceeds production, the persistent lack of ATP causes impaired myosin-actin cross-bridging, because ATP is essential for detaching myosin from actin. Therefore, cross-bridge failure dominates, rather than enhanced glycogenolysis or increased calcium reuptake, which are energy-dependent but less directly linked to acute fatigue.

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