Final answer:
The author suggests that aerobic exercise such as cycling and walking enhances the cardiovascular system's ability to deliver oxygen, improving endurance and stamina.
Step-by-step explanation:
Implication of Aerobic Exercise
The author implies that aerobic exercise is beneficial for improving the efficiency of the cardiovascular system. By engaging in activities like cycling, walking, and swimming, one can bolster the capacity for oxygen delivery to various parts of the body including the heart, lungs, and blood vessels.
This increase in oxygen efficiency, over time, leads to enhancements in both endurance and stamina. It is understood that aerobic exercises utilize low to moderate levels of exertion that can be maintained over extensive periods, thus leveraging the body's aerobic energy-generating process.
Therefore, the correct implication from the author's statement would be: aerobic exercise improves the oxygen delivery to the heart, lungs, and blood vessels.