Aerobics Trainer Exercise Physiology & Conditioning Flashcards

Which energy system is the PRIMARY source during a 400-meter sprint lasting approximately 50 seconds?

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.

Cardiac output is calculated by multiplying heart rate by which other variable?

Answer: Stroke volume

Cardiac output (Q) = Heart Rate × Stroke Volume, expressing how much blood the heart pumps per minute.

The Fick equation relates VO2 to cardiac output and which other measurement?

Answer: Arteriovenous oxygen difference

The Fick equation states VO2 = Cardiac Output × Arteriovenous O2 Difference (a-vO2 diff), reflecting oxygen extraction by tissues.

Which muscle fiber type has the HIGHEST oxidative capacity and is most fatigue-resistant?

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.

During prolonged aerobic exercise, which fuel source becomes increasingly important as muscle glycogen is depleted?

Answer: Free fatty acids (FFA)

As glycogen stores fall during prolonged exercise, adipose-derived free fatty acids become the dominant fuel through beta-oxidation.

What is the primary physiological purpose of the warm-up period before aerobic exercise?

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.

Which principle of training states that gains are lost when training stimulus is removed?

Answer: Reversibility

The reversibility (or detraining) principle states that fitness adaptations diminish when training ceases or significantly decreases.