ANATOMY

Detailed explanation-1: -Your heart can also increase its stroke volume by pumping more forcefully or increasing the amount of blood that fills the left ventricle before it pumps. Generally speaking, your heart beats both faster and stronger to increase cardiac output during exercise.

Detailed explanation-2: -Cardiac output is the product of heart rate (HR) and stroke volume (SV) and is measured in liters per minute. HR is most commonly defined as the number of times the heart beats in one minute. SV is the volume of blood ejected during ventricular contraction or for each stroke of the heart.

Detailed explanation-3: -Initially, as HR increases from resting to approximately 120 bpm, cardiac output will rise. As HRincreases from 120 to 160 bpm, cardiac output remains stable, since the increase in rate is offset by decreasing ventricular filling time and, consequently, SV.

Detailed explanation-4: -During exercise, the cardiac output increases more than the total resistance decreases, so the mean arterial pressure usually increases by a small amount. Pulse pressure, in contrast, markedly increases because of an increase in both stroke volume and the speed at which the stroke volume is ejected.