Case Study: Scenario: A marathon runner, nearing the finish line, experiences intense fatigue, muscle cramps, and a feeling of “heaviness” in her legs. Question: What is the primary physiological factor contributing to these symptoms?

The recovery stroke of muscle contraction is powered by the breakdown of ATP into ADP and P.

Case Study: Scenario: A 30-year-old man is lifting weights at the gym when he feels a sudden, sharp pain in his shoulder. He is unable to continue lifting weights and experiences pain when he tries to move his arm. Question: Which muscle is most likely injured?

The recovery stroke of muscle contraction is powered by the breakdown of ATP into ADP and P.

What is the difference between hypertrophy and atrophy?

Case Study: Scenario: A 70-year-old woman presents with a history of frequent falls, difficulty rising from a chair, and a waddling gait. Her family notes she appears to have lost muscle mass, especially in her arms and legs. Question: Which of the following conditions is the most likely cause?

Properly label the phases of cross-bridge movement: Phase 1 is , phase 2 is , phase 3 is , phase 4 is , phase 5 is , and phase 6 is . Word bank (please copy exact spelling): hydrolysis of ATP cross-bridge release power stroke myosin formation exposure of active sites recovery stroke actin binding cross-bridge formation forming of ATP

Case Study: A Weightlifter’s Struggle Scenario: A weightlifter is attempting a new personal best in the bench press. As he lowers the barbell towards his chest, he feels a sudden and intense pain in his right shoulder. The weightlifter immediately stops the exercise and seeks medical attention. An examination reveals that he has torn his rotator cuff. Question: Considering the mechanics of a bench press and the function of the rotator cuff muscles, which muscle is MOST likely involved in the weightlifter’s injury?

Properly label the structures: Structure 1: Structure 2: Structure 3: Structure 4: Structure 5: Structure 6: Structure 7: Structure 8: Structure 9: Structure 10:

Explain the steps involved in the sliding filament model of muscle contraction.   Step 1: Step 2: Step 3: Step 4: