CAT Aerobics Trainer Exercise Physiology & Conditioning 2 — Questions and Answers
Question 1: Which energy system is the PRIMARY source during a 400-meter sprint lasting approximately 50 seconds?
- ATP-PCr system
- Glycolytic (lactic acid) system (Correct answer)
- Oxidative phosphorylation
- Beta-oxidation
Correct answer: Glycolytic (lactic acid) system
The glycolytic system dominates efforts lasting roughly 30–120 seconds, making it the primary contributor for a 400-meter sprint.
Question 2: Cardiac output is calculated by multiplying heart rate by which other variable?
- Total peripheral resistance
- Stroke volume (Correct answer)
- Ejection fraction
- Oxygen pulse
Correct answer: Stroke volume
Cardiac output (Q) = Heart Rate × Stroke Volume, expressing how much blood the heart pumps per minute.
Question 3: The Fick equation relates VO2 to cardiac output and which other measurement?
- Respiratory exchange ratio
- Arteriovenous oxygen difference (Correct answer)
- Tidal volume
- Alveolar ventilation
Correct answer: Arteriovenous oxygen difference
The Fick equation states VO2 = Cardiac Output × Arteriovenous O2 Difference (a-vO2 diff), reflecting oxygen extraction by tissues.
Question 4: Which muscle fiber type has the HIGHEST oxidative capacity and is most fatigue-resistant?
- Type IIx (fast-twitch glycolytic)
- Type IIa (fast-twitch oxidative)
- Type I (slow-twitch oxidative) (Correct answer)
- Type IIb (super-fast glycolytic)
Correct answer: Type I (slow-twitch oxidative)
Type I slow-twitch fibers are densely packed with mitochondria and myoglobin, giving them superior oxidative capacity and fatigue resistance.
Question 5: During prolonged aerobic exercise, which fuel source becomes increasingly important as muscle glycogen is depleted?
- Creatine phosphate
- Free fatty acids (FFA) (Correct answer)
- Ketone bodies
- Dietary protein
Correct answer: Free fatty acids (FFA)
As glycogen stores fall during prolonged exercise, adipose-derived free fatty acids become the dominant fuel through beta-oxidation.
Question 6: What is the primary physiological purpose of the warm-up period before aerobic exercise?
- Maximizing glycogen storage
- Increasing muscle temperature and blood flow to active muscles (Correct answer)
- Reducing heart rate variability
- Activating the parasympathetic nervous system
Correct answer: Increasing muscle temperature and blood flow to active muscles
Warm-up raises muscle temperature, enhances enzyme activity, and increases oxygen delivery to working muscles, reducing injury risk.
Question 7: Which principle of training states that gains are lost when training stimulus is removed?
- Specificity
- Overload
- Reversibility (Correct answer)
- Progressive resistance
Correct answer: Reversibility
The reversibility (or detraining) principle states that fitness adaptations diminish when training ceases or significantly decreases.
CAT Aerobics Trainer Exercise Physiology & Conditioning 2
Which energy system is the PRIMARY source during a 400-meter sprint lasting approximately 50 seconds?