Final answer:
The heart feels like it's pounding during vigorous exercise due to an increase in cardiac output, which is a product of increased heart rate and stroke volume. Stroke volume is not artificial; it's a measurable amount of blood pumped with each heartbeat. Regular exercise improves the heart's efficiency and increases overall cardiovascular health.
Step-by-step explanation:
The physiological concept that explains why one's heart feels like it's pounding during vigorous exercise is based on the increased cardiac response and cardiac output. As one exercises, their heart rate and stroke volume both increase to meet the body's higher demand for oxygenated blood. The heart, as a muscle, responds to exercise by pumping more blood, and this rise in cardiac output also leads to an increase in blood pressure.
During exercise, the body needs more oxygenated blood, and the heart achieves this by increasing cardiac output. A common misconception is that stroke volume is an artificial number; it's actually quite a real and significant variable representing the volume of blood pumped from the ventricles with each beat, contributing to cardiac output along with heart rate. Regular exercise enhances cardiovascular health by making the heart more efficient, able to deliver the same amount of blood with fewer beats, and increases tissue perfusion.