Which of the following is an effect of regular aerobic exercise?

Regular aerobic exercise is known for its significant positive impact on cardiovascular health, which is reflected in improved cardiovascular fitness. This enhancement occurs because aerobic exercise strengthens the heart muscle, allowing it to pump blood more efficiently. Over time, as the body adapts to frequent aerobic activity, there is an increase in the number of capillaries in the muscles, improved oxygen uptake and delivery to tissues, and better overall circulation.

As a result, individuals engaging in regular aerobic exercise typically experience lower resting heart rates and improved stamina, enabling them to perform physical activities with greater ease and endurance. This adaptation not only supports daily activities but also lowers the risk of cardiovascular diseases.

Factors like decreased lung capacity and lower tolerance to physical activity, associated with inactivity or underlying health issues, would contrast with the benefits gained from regular aerobic exercise. Thus, "improved cardiovascular fitness" accurately reflects the numerous health benefits derived from consistent engagement in aerobic activities.