How is cardiac output defined?

Cardiac output is defined as the volume of blood pumped by each ventricle of the heart per minute, which is a measure of the heart's efficiency and the body's ability to deliver oxygen and nutrients to tissues. The correct choice takes into account the functional aspect of how blood circulation supports active cells, emphasizing the importance of blood delivery in relation to metabolic needs during physical activity.

Cardiac output is typically calculated by multiplying stroke volume (the amount of blood pumped from the heart with each beat) by heart rate (the number of beats per minute). This reflects not just the raw volume of blood but how that volume is utilized to meet the demands of various tissues, particularly during exercise.

The understanding of cardiac output is crucial for personal trainers and fitness professionals, as it can offer insights into an individual's cardiovascular fitness and the effectiveness of their training regimen.