What does diastolic pressure indicate?

Diastolic pressure refers to the measurement of blood pressure in the arteries when the heart is relaxed and filling with blood between beats. This period of rest allows the heart chambers to refill with blood before the next contraction, and the diastolic number indicates how much pressure is exerted on the artery walls during this resting phase.

Understanding diastolic pressure is crucial because it helps gauge the minimum level of pressure needed to ensure that blood continues to flow to vital organs even while the heart is not actively pumping. This value is vital in assessing overall cardiovascular health, as excessively high diastolic pressure can indicate issues such as poor arterial elasticity or high blood volume.

In the context of the other options, the pressure during heart contraction pertains to systolic pressure, the total blood volume does not directly relate to blood pressure readings, and heart rate during physical activity reflects the heart's response to exercise rather than blood pressure itself. Thus, the correct choice highlights the importance of resting pressure within the cardiovascular system.