What is the term for the ability of the heart and lungs to supply oxygen to working muscles during sustained physical activity?

The term that refers to the ability of the heart and lungs to supply oxygen to working muscles during sustained physical activity is aerobic capacity. This concept encompasses the efficiency and effectiveness of the cardiovascular and respiratory systems in delivering oxygen to the muscles, as well as the muscles' ability to utilize that oxygen for energy production during prolonged exercise.

Aerobic capacity is an essential aspect of overall fitness and is often measured through tests such as VO2 max, which indicates the maximum amount of oxygen the body can use during intense exercise. This ability is critical for endurance activities and has a significant impact on performance in activities such as running, cycling, and swimming.

The other options, while related to physical fitness, do not directly describe this specific physiological function. Anabolism refers to the metabolic processes involved in building up molecules, muscular endurance pertains to the ability of muscles to sustain repeated contractions over time, and cardiac output is a measure of the blood the heart pumps per minute but does not encompass the total aerobic capacity of the body.