ACSM Personal Trainer Certification Practice Exam

Which of the following describes the acute cardiovascular response to aerobic exercise?

1. Decrease in heart rate and increase in blood pressure

2. Increase in heart rate, stroke volume, and cardiac output

3. No change in blood lactate

4. Decrease in pulmonary ventilation

The correct answer is: Increase in heart rate, stroke volume, and cardiac output

The acute cardiovascular response to aerobic exercise primarily involves an increase in heart rate, stroke volume, and cardiac output. When a person engages in aerobic activities, such as running or cycling, the demand for oxygen in the working muscles increases significantly. To meet this demand, the body enhances its cardiovascular function. With the onset of exercise, the heart rate rises almost immediately to pump more blood—and therefore more oxygen—to the muscles. Stroke volume, which is the amount of blood ejected with each heartbeat, also increases as the heart works more efficiently. Consequently, this leads to an overall increase in cardiac output, which is the total volume of blood the heart pumps per minute (calculated as heart rate multiplied by stroke volume). This combination ensures that the working muscles receive sufficient oxygen and nutrients to sustain aerobic metabolism. Other options do not accurately represent the acute cardiovascular response. Typically, heart rate and blood pressure do not decrease during aerobic exercise, blood lactate levels generally do increase with sustained high-intensity exertion, and pulmonary ventilation usually increases to facilitate greater oxygen uptake and carbon dioxide removal.