What is expected to happen to stroke volume (SV) with regular exercise training?

Regular exercise training leads to an increase in stroke volume (SV). Stroke volume refers to the amount of blood pumped by the heart with each beat. With consistent endurance training, several physiological adaptations occur that enhance the heart's efficiency.

One of the main adaptations is an increase in the size and strength of the heart muscle, particularly the left ventricle. As the heart becomes better conditioned, it can pump more blood per contraction. Additionally, exercise improves the efficiency of the cardiovascular system, leading to better venous return and increased preload (the volume of blood in the ventricles at the end of diastole). As a result, the heart can eject a greater volume of blood with each beat, which effectively increases stroke volume.

Another factor is the improved oxygen delivery and uptake to working muscles, which places less strain on the heart during physical activity. This adaptation allows for better performance during exercise and can also lead to lower heart rates, as the heart becomes more efficient at producing the same output.

Therefore, the consistent increase in stroke volume is a key benefit of regular exercise training, contributing to overall cardiovascular fitness and endurance performance.