What does stroke volume measure?

Stroke volume measures the volume of blood ejected by the heart with each beat. It is an important physiological parameter as it reflects how efficiently the heart is functioning to supply oxygenated blood to the body. Understanding stroke volume is crucial for assessing cardiovascular health and fitness, as it directly influences cardiac output, which is the total volume of blood the heart pumps in a minute. This measure gives insight into the heart's strength and efficiency, particularly during exercise, as higher stroke volume typically indicates better cardiovascular fitness.

While the other options might involve related cardiovascular concepts, they do not specifically define stroke volume. The amount of oxygen in the blood pertains to oxygen saturation, while the volume of blood pumped per heart rate considers a different aspect of cardiac function. Total blood volume in the body does not directly correlate to stroke volume and involves other physiological considerations.