CFP Exercise Science & Physiology 2 — Questions and Answers
Question 1: Which energy system is the PRIMARY source of ATP during a maximal-effort sprint lasting 6–10 seconds?
- Oxidative phosphorylation
- Glycolytic system
- Phosphocreatine (ATP-PCr) system (Correct answer)
- Beta-oxidation
Correct answer: Phosphocreatine (ATP-PCr) system
The ATP-PCr system provides immediate, high-power energy for very short maximal efforts of 6–10 seconds without requiring oxygen.
Question 2: During aerobic exercise, which organelle is primarily responsible for ATP production via oxidative phosphorylation?
- Nucleus
- Ribosome
- Mitochondria (Correct answer)
- Golgi apparatus
Correct answer: Mitochondria
Mitochondria contain the electron transport chain and ATP synthase, making them the site of aerobic ATP production.
Question 3: A client's heart rate fails to increase appropriately during progressively harder exercise. This condition is called:
- Bradycardia
- Chronotropic incompetence (Correct answer)
- Heart block
- Vasovagal syncope
Correct answer: Chronotropic incompetence
Chronotropic incompetence is the inability of the heart to increase rate appropriately in response to increased exercise demand.
Question 4: Which muscle fiber type has the HIGHEST oxidative capacity and is most resistant to fatigue?
- Type IIx (fast-twitch glycolytic)
- Type IIa (fast-twitch oxidative)
- Type I (slow-twitch) (Correct answer)
- Type IIb (fast-twitch)
Correct answer: Type I (slow-twitch)
Type I (slow-twitch) fibers have abundant mitochondria and myoglobin, giving them high oxidative capacity and excellent fatigue resistance.
Question 5: The Fick equation defines VO₂ as the product of cardiac output and which other variable?
- Respiratory exchange ratio
- Arteriovenous oxygen difference (a-vO₂ diff) (Correct answer)
- Tidal volume
- Pulmonary diffusion capacity
Correct answer: Arteriovenous oxygen difference (a-vO₂ diff)
The Fick equation states VO₂ = Cardiac Output × (a-vO₂ difference), reflecting how much oxygen is extracted by working tissues.
Question 6: What happens to stroke volume during moderate-intensity aerobic exercise in a trained individual?
- It decreases due to faster heart rate
- It remains unchanged from resting values
- It increases due to enhanced ventricular filling and contractility (Correct answer)
- It drops after the first 5 minutes
Correct answer: It increases due to enhanced ventricular filling and contractility
Trained individuals show increased stroke volume during moderate exercise due to greater venous return, ventricular preload, and myocardial contractility.
Question 7: Which respiratory response occurs when exercise intensity exceeds the lactate threshold?
- Breathing rate decreases to conserve CO₂
- Ventilation increases disproportionately (ventilatory threshold) (Correct answer)
- Tidal volume drops to baseline
- Respiratory exchange ratio falls below 0.7
Correct answer: Ventilation increases disproportionately (ventilatory threshold)
Above the lactate threshold, excess CO₂ from bicarbonate buffering of lactic acid drives a disproportionate rise in ventilation called the ventilatory threshold.
CFP Exercise Science & Physiology 2
Which energy system is the PRIMARY source of ATP during a maximal-effort sprint lasting 6–10 seconds?