ACSM Personal Trainer Certification Practice Exam

What is the primary effect of chronic aerobic training on stroke volume?

1. Increased resting stroke volume

2. Decreased stroke volume during exercise

3. Increased resting heart rate

4. Decreased arterial oxygen levels

The correct answer is: Increased resting stroke volume

Chronic aerobic training leads to physiological adaptations in the cardiovascular system, one of the primary effects being an increase in resting stroke volume. Stroke volume refers to the amount of blood the heart pumps with each beat, and it is influenced by factors such as the size of the heart, the strength of the heart's contractions, and the amount of blood filling the heart before it contracts (preload). With chronic aerobic training, several adaptations occur: the heart becomes larger and stronger, which allows it to pump more blood per beat. This increased efficiency means that, at rest, a trained individual can achieve a sufficient blood flow to maintain bodily functions with fewer heartbeats. Consequently, this results in a higher resting stroke volume—allowing the heart to work more efficiently, ultimately reducing the resting heart rate. The other options incorrectly suggest effects that do not align with what is observed with chronic aerobic training. For instance, stroke volume during exercise does not decrease; instead, it generally increases due to the improved capacity of the heart and vasculature to deliver oxygenated blood to working muscles. Increased resting heart rate contradicts the findings as well; with increased stroke volume, the heart rate tends to decrease. Lastly, decreased arterial oxygen levels would not be a result of improved