What does the term cardiac output describe?

The term cardiac output specifically refers to the volume of blood that the heart pumps per minute. This metric is crucial in understanding how effectively the heart is functioning and how well it meets the body’s demands for oxygen and nutrients during various activities. Cardiac output is calculated by multiplying the heart rate (the number of beats per minute) by the stroke volume (the amount of blood ejected by the heart with each beat).

This measurement is significant in both fitness and clinical settings, as it offers vital insights into cardiovascular health and overall physiological efficiency. High cardiac output can indicate an increased ability to deliver oxygen to the body, while low output may suggest heart failure or other cardiovascular issues.

The other answer choices pertain to different aspects of the cardiovascular system: total blood volume refers to the overall quantity of blood in the body, the amount of blood in the heart at rest speaks to preload and the heart's filling status, and blood pressure in the arteries relates to the force exerted by circulating blood against the walls of blood vessels. While these concepts are important to cardiovascular health, they do not describe the specific function of cardiac output.