National Physical Therapy Examination (NPTE) Practice Exam

The measure that best reflects improvement in the cardiopulmonary system after two weeks of supervised exercise is the decreased heart rate response to exercise. This is an important indicator as it suggests that the heart is becoming more efficient due to improved cardiovascular fitness.

When a person's cardiovascular system becomes more conditioned, it requires fewer heartbeats to deliver the same amount of blood and oxygen to the muscles during physical activity. A lower heart rate response during exercise is indicative of enhanced stroke volume and improved oxygen uptake by the body. This adaptation is a desirable outcome of regular exercise and is commonly observed in individuals who have engaged in a structured physical fitness program.

In contrast, factors like delayed cardiovascular response upon rising or decreased respiratory rate during exercise may not directly indicate improved cardiovascular efficiency or conditioning. Increased cardiovascular peripheral resistance is generally unfavored as it can indicate an adverse response and may compromise overall cardiovascular health. A decreased heart rate response to exercise, therefore, is a direct measure of the cardiopulmonary system's enhancement following consistent physical activity.