Final answer:
A fast time and low heart rate during the one-mile walk test suggests a high level of cardiorespiratory endurance, as it shows that the heart efficiently pumps blood and the body uses oxygen effectively during sustained physical activity.
Step-by-step explanation:
True, a fast time and a low heart rate during the one-mile walk test indeed indicate a high level of cardiorespiratory endurance. Cardiorespiratory endurance is the ability of the heart, lungs and blood vessels to deliver oxygen to your body tissues during sustained physical activity. The one-mile walk test is a sub-maximal test that estimates an individual's aerobic fitness. A quicker completion time combined with a lower heart rate upon completion indicates that the heart doesn't have to work as hard to pump blood and oxygen to the muscles, signaling good cardiorespiratory fitness. This means that the individual can sustain aerobic activity for extended periods, reflecting their level of fitness.
With regular aerobic exercise, the heart's efficiency improves, and so does the body's ability to use oxygen more effectively. These exercises involve sustained activity that uses slow-twitch muscle fibers, which are better at using oxygen and promoting endurance. Individuals may vary in their response to aerobic exercises due to genetic differences in these muscle fibers, leading to different levels of endurance improvements.