What is cardiac output?

Cardiac output refers to the volume of blood that is ejected from the heart in one minute. It is a crucial measure in both exercise physiology and overall cardiovascular health. More specifically, it is commonly defined as the amount of blood pumped by the left side of the heart, since the left ventricle ejects oxygen-rich blood to the rest of the body. This process is essential for delivering nutrients and oxygen to tissues while also removing waste products.

Understanding the significance of cardiac output involves recognizing its components: it is typically calculated by multiplying stroke volume (the amount of blood pumped with each heartbeat) by heart rate (the number of beats per minute). Thus, cardiac output provides insight into how effectively the heart is functioning, particularly during physical activity when the demand for oxygen increases.

Other options provided in this question either mischaracterize the process or focus on different aspects of blood flow and volume. For instance, the volume of blood ejected from the right side of the heart focuses only on deoxygenated blood returning to the lungs and does not represent the systemic circulation's effort. Options concerning total blood volume or hourly measurements are irrelevant to the definition of cardiac output, which is strictly focused on a minute-to-minute performance of the heart. Understanding cardiac output helps