Question

read the text and review the chart
the standard plank test is an easy way to measure the strength and endurance of your core muscles. you can perform the test at home. all you need is a stopwatch and a partner.
to perform the standard plank test:

• move into the plank position, positioning feet and hands on the floor as if doing a push - up.
• hold this up position as long as possible, being careful to keep your back straight and flat.
• have a partner time how long you can hold the pose. the timer should be stopped when your hips begin to sag or rise.

how does the performance chart included in this document help clarify the standard plank test procedure?
○ it illustrates the main purpose of the test for test takers
○ it provides test takers with tips for improving endurance.
○ it shows test takers how test results should be recorded.
○ it helps test takers interpret and evaluate their test results

Explanation:

A performance chart in a fitness - related document (like the standard plank test) is typically used to help test - takers understand what their results mean. The main purpose of the test (measuring core strength and endurance) is already stated in the text. Tips for improving endurance are not the main function of a performance chart. Recording results is part of the procedure (using a stopwatch), but the chart's role is more about evaluation. A performance chart would categorize results (e.g., poor, average, good) based on time held in the plank position, which helps test - takers interpret and evaluate their performance.

Answer:

It helps test takers interpret and evaluate their test results.