With long-term exercise, how does stroke volume change?

With long-term exercise, how does stroke volume change?

• A. Decreases
• B. Increases
• C. Unchanges
• D. Fluctuates greatly

Answer: (B)

With long-term exercise, the heart adapts to become more efficient at pumping blood, increasing how much blood is pushed out with each beat. The left ventricle grows slightly larger and fills more effectively, while plasma volume expands, boosting venous return and end-diastolic volume. These changes mean the heart can contract more forcefully and eject more blood per beat, so stroke volume increases. As a result, you can deliver greater oxygen to the working muscles without needing a proportionally higher heart rate, though resting heart rate may fall due to improved efficiency. So stroke volume increases, not decreases, remains unchanged, or fluctuates unpredictably.

With long-term exercise, the heart adapts to become more efficient at pumping blood, increasing how much blood is pushed out with each beat. The left ventricle grows slightly larger and fills more effectively, while plasma volume expands, boosting venous return and end-diastolic volume. These changes mean the heart can contract more forcefully and eject more blood per beat, so stroke volume increases. As a result, you can deliver greater oxygen to the working muscles without needing a proportionally higher heart rate, though resting heart rate may fall due to improved efficiency. So stroke volume increases, not decreases, remains unchanged, or fluctuates unpredictably.