During repetitive high intensity muscle contraction, a point will be reached in which the muscle is unable to continue generating the necessary force to maintain the desired work output. At this point we would consider the muscle to be fatigued. How does fatigue occur?
In your answer, 1) describe how cross bridges are formed during contraction (i.e., the chemomechanical coupling model) and then 2) discuss the cause of fatigue with specific attention on how the repetitive high intensity contractions induce a depression in pH and elevate Pi. Your discussion should include how these changes cause a reduction in the force and velocity of contraction in the context of the chemomechanical coupling model.
