Which combination of tests assesses muscular endurance?

The choice that accurately reflects a combination of tests for assessing muscular endurance is the timed push-ups and sit-ups. This selection is particularly relevant because both push-ups and sit-ups are exercises that specifically target muscular endurance.

Muscular endurance refers to the ability of a muscle or group of muscles to perform repeated contractions over a period of time. Timed push-ups measure the endurance of the upper body muscles, particularly the chest, shoulders, and triceps, by assessing how many repetitions can be done in a set time. Similarly, timed sit-ups focus on the endurance of the abdominal muscles, evaluating how many sit-ups a person can perform within a given timeframe.

In contrast, the other options present tests that do not primarily measure muscular endurance. The sit-and-reach test and stork test focus on flexibility and balance, respectively. The 10-60 yard dash and vertical jump are performance tests emphasizing speed and explosive strength rather than endurance. Lastly, the Harvard step test and Cooper's run are primarily used to assess cardiovascular fitness and aerobic capacity. Each of these alternatives targets different aspects of physical fitness, which is why they do not align with the assessment of muscular endurance as effectively as timed push-ups and sit-ups do.