What does cardiac output measure?

Cardiac output is defined as the volume of blood pumped by the heart per minute, which is why the correct answer is focused on this aspect. It serves as a critical measure for understanding overall heart function and circulatory efficiency. Specifically, cardiac output is a product of stroke volume (the volume of blood pumped with each heartbeat) and heart rate (the number of heartbeats per minute). Therefore, measuring cardiac output provides valuable insight into how well the heart is supplying blood to meet the body's demands during various levels of activity.

The concept is essential in many clinical and exercise settings, as it helps assess cardiovascular health and can indicate the heart's capability to transport oxygen and nutrients throughout the body effectively. Understanding cardiac output is crucial for exercise physiologists and health professionals monitoring cardiovascular performance during rest and exercise.