Which of the following happen during a cardiovascular training session?

During a cardiovascular training session, both stroke volume and cardiac output increase as the body works to meet the elevated demands for oxygen and nutrients by the muscles.

Stroke volume refers to the amount of blood the heart pumps with each beat, and during exercise, the heart becomes more efficient, leading to an increase in this volume. As the heart pumps more blood, cardiac output, which is the total volume of blood the heart pumps per minute, also increases, as it is calculated by multiplying stroke volume by heart rate.

This response is essential for maintaining physical performance and ensuring that the working muscles receive the necessary oxygen supply during sustained activities. When engaging in cardiovascular exercises, the body adapts to enhance its efficiency, which is reflected in the upward trend of both stroke volume and cardiac output.

The other choices describe scenarios that do not align with the physiological responses typically observed during cardiovascular exercise, where increases in stroke volume and cardiac output facilitate better performance and endurance.