What aspect of stroke volume changes during the concentric phase of resistance training?

During the concentric phase of resistance training, stroke volume primarily remains constant due to the nature of muscular contractions and the demands placed on the cardiovascular system. While the heart rate may increase to meet the metabolic needs of the working muscles, the stroke volume—a measure of the amount of blood ejected by the heart with each beat—does not necessarily change dramatically during this phase of exercise.

In resistance training, particularly at moderate to high intensities, the muscles contract isometrically and concentrically, leading to increased intramuscular pressure. This pressure can momentarily restrict venous return (the return of blood to the heart), potentially stabilizing stroke volume instead of promoting a significant increase or decrease. Thus, although there are changes in cardiovascular dynamics during different types of exercise, the balance of factors during the concentric phase typically supports a relative constancy in stroke volume.

Other choices suggest variations that do not accurately reflect the physiological responses typically seen during resistance training. Increases in stroke volume usually occur at lower intensities or with prolonged aerobic exercise rather than during short, high-intensity bouts typical of resistance training, where values remain more stable. Fluctuations are plausible in more complex cardiovascular responses, but in the context of steady-state resistance training, stroke