Final answer:
The Rockport Walking Test and the Cooper 12-minute run are both good measures of endurance fitness, as they help in estimating an individual's vo2 max and assessing their ability to perform activities for extended periods.
Step-by-step explanation:
The question "Which of the following is a good measure for endurance fitness?" presents two options: the Rockport Walking Test and the Cooper 12-minute run. Both of these are indeed measures of endurance fitness. The Rockport Walking Test is designed to estimate a person's vo2 max by having them walk as fast as possible for one mile. This test is particularly good for those who are new to exercise or cannot perform a high-intensity workout. On the other hand, the Cooper 12-minute run test is a field test to estimate an individual's aerobic capacity. In this test, a participant runs as far as possible for 12 minutes, and the distance covered is used to estimate their vo2 max.
Therefore, the answer would be 'Both A & B' as both tests are used to gauge different aspects of endurance fitness. Endurance fitness helps individuals to perform activities over extended periods. These tests are useful diagnostics tools in understanding one's current level of fitness and in planning a training regime to improve endurance.