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Sports & Exercise Physiology Flashcards

7 cards from real CSN practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.

Read the first 7 Sports & Exercise Physiology flashcards as text

  1. A sprinter performs a maximal 6-second effort. Which energy system supplies the majority of ATP?

    Answer: Phosphocreatine (ATP-PCr) system

    The ATP-PCr system dominates maximal efforts lasting roughly 0-10 seconds.

  2. Which enzyme is considered the rate-limiting step of glycolysis?

    Answer: Phosphofructokinase (PFK)

    PFK is the key regulatory enzyme of glycolysis and is stimulated by rising ADP and AMP.

  3. During a 400 m run lasting about 50 seconds, which system contributes most to ATP production?

    Answer: Anaerobic glycolysis

    Efforts of roughly 30 seconds to 2 minutes rely mostly on fast (anaerobic) glycolysis.

  4. The 'crossover concept' describes what shift as exercise intensity increases?

    Answer: From fat to carbohydrate as the main fuel

    As intensity rises, carbohydrate's share of energy expenditure rises and fat's share falls.

  5. Excess post-exercise oxygen consumption (EPOC) is partly used to do which of the following?

    Answer: Resynthesize phosphocreatine and restore oxygen stores

    EPOC supports PCr resynthesis, oxygen restoration in myoglobin and blood, and elevated temperature and hormone effects.

  6. What is the net ATP yield from anaerobic glycolysis of one glucose molecule?

    Answer: 2 ATP

    Glycolysis from glucose yields a net 2 ATP (3 if starting from muscle glycogen).

  7. An athlete's respiratory exchange ratio (RER) is 0.85 during steady exercise. What does this suggest?

    Answer: A mixture of fat and carbohydrate oxidation

    An RER of 0.85 lies between 0.70 (fat) and 1.00 (carbohydrate), indicating mixed fuel use.

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