What are the goals of training oxygen transportation?

• A. Decrease lung capacity
• B. Enlarge & strengthen the heart, larger stroke volume, higher cardiac output
• C. Increase resting heart rate
• D. Reduce cardiac output

Answer: (B)

The aim of training oxygen transportation is to boost the heart’s ability to move oxygen-rich blood to the muscles that are working. With endurance training, the heart adapts by getting stronger and more efficient, so it can eject more blood with each beat. This means a larger stroke volume, which is the amount of blood pumped per heartbeat. When stroke volume increases, the heart can supply the same amount of blood with fewer beats, or deliver more blood overall during activity, which raises cardiac output (the total blood pumped per minute). Better cardiac output means more oxygen reaches working muscles, supporting longer and harder exercise.

That’s why the best description is enlarging and strengthening the heart, leading to a larger stroke volume and higher cardiac output. Other options don’t fit because training doesn’t aim to decrease lung capacity or reduce cardiac output; and increasing resting heart rate is not a typical goal of aerobic adaptation, since endurance training usually lowers resting heart rate as the heart becomes more efficient.