NSCA-CPT Exercise Physiology 4 — Questions and Answers
Question 1: Which of the following BEST describes the 'oxygen deficit' at the onset of exercise?
- The amount of oxygen stored in myoglobin
- The lag between oxygen demand and aerobic system delivery at exercise onset (Correct answer)
- The difference between VO2max and resting VO2
- Total oxygen consumed during EPOC
Correct answer: The lag between oxygen demand and aerobic system delivery at exercise onset
Oxygen deficit is the difference between the oxygen required at exercise onset and the oxygen actually consumed before steady state is reached.
Question 2: An increase in core body temperature during exercise affects hemoglobin's oxygen-binding affinity by:
- Increasing affinity (left shift of oxyhemoglobin curve)
- Decreasing affinity (right shift of oxyhemoglobin curve) (Correct answer)
- Having no effect on affinity
- Eliminating oxygen release to tissues
Correct answer: Decreasing affinity (right shift of oxyhemoglobin curve)
Elevated temperature causes a rightward shift of the oxyhemoglobin dissociation curve, reducing hemoglobin's affinity and enhancing O2 release to working muscles.
Question 3: Which enzyme is rate-limiting for the glycolytic pathway?
- Creatine kinase
- Phosphofructokinase (PFK) (Correct answer)
- Lactate dehydrogenase
- Hexokinase
Correct answer: Phosphofructokinase (PFK)
Phosphofructokinase (PFK) is the key regulatory enzyme of glycolysis, controlling the rate of glucose metabolism.
Question 4: Which of the following best describes the concept of 'metabolic specificity' in training?
- Training must mimic exact sport movements
- Energy systems trained must match those predominantly used in competition (Correct answer)
- All exercises should be performed at the same intensity
- Nutrition must be specific to the training phase
Correct answer: Energy systems trained must match those predominantly used in competition
Metabolic specificity means training should stress the same energy pathways (phosphagen, glycolytic, oxidative) that the target sport or activity demands.
Question 5: Peripheral vascular resistance during aerobic exercise is PRIMARILY reduced by:
- Increased sympathetic tone in working muscles
- Local vasodilation due to metabolic byproducts in active muscles (Correct answer)
- Decreased cardiac output
- Increased blood viscosity
Correct answer: Local vasodilation due to metabolic byproducts in active muscles
Metabolic byproducts (CO2, lactic acid, adenosine, heat) cause local vasodilation in active muscles, reducing peripheral resistance and increasing blood flow.
Question 6: Which adaptation to resistance training is PRIMARILY responsible for strength gains in the first 4–8 weeks of training in untrained individuals?
- Muscle hypertrophy
- Neural adaptations and improved motor unit recruitment (Correct answer)
- Increased muscle fiber number (hyperplasia)
- Connective tissue thickening
Correct answer: Neural adaptations and improved motor unit recruitment
Early strength gains are predominantly neurological — improved motor unit recruitment, synchronization, and reduced inhibition — before significant hypertrophy occurs.
Question 7: Which condition describes the point during graded exercise testing when ventilation increases disproportionately relative to oxygen consumption?
- VO2max
- Ventilatory threshold (VT) (Correct answer)
- Respiratory exchange ratio of 0.85
- Anaerobic threshold of 50% VO2max
Correct answer: Ventilatory threshold (VT)
The ventilatory threshold (VT) is identified when ventilation rises nonlinearly relative to VO2, signaling increased reliance on anaerobic metabolism and CO2 buffering.
NSCA-CPT Exercise Physiology 4
Which of the following BEST describes the 'oxygen deficit' at the onset of exercise?