Why does sustained muscle contraction lead to increased perceived effort and diminished force output during endurance activities?

💡 Explanation

Reduced calcium availability within the sarcoplasmic reticulum diminishes the number of available binding sites for troponin. This impaired calcium release inhibits the cross-bridge cycling mechanism, therefore reducing force production and contributing to the sensation of fatigue, rather than increased glycogen synthesis or elevated creatine phosphate levels improving output.

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