# Leg Extension Test

Testing and measurement are the means of collecting information upon which subsequent performance evaluations and decisions are made but in the analysis we need to bear in mind the factors that may influence the results.

### Objective

The objective of the leg extension test is to evaluate the strength of an athlete's quadriceps.

### Required Resources

To undertake this test you will require:

• Universal knee flexor/extensor bench
• Assistant

### How to conduct the test

This test requires the athlete to complete as many leg extensions as possible with no rest.

• The athlete warms up for 10 minutes
• The assistant sets the resistance close to the athlete’s one repetition maximum load
• The athlete sits on the end of the bench with the padded edge of the bench against the posterior surface of the knee joint, the feet hooked behind the padded rollers and the hands grasping the bench just behind their buttocks
• The athlete conducts leg extensions until they are unable to continue
• The assistant counts the number of successful leg extensions
• If the number of leg extensions exceeds 8 then the athlete rests for 10 minutes, the assistant increases the resistance and the athlete repeats the test
• The assistant uses the maximum load calculator to determine the athlete's 1RM

### Analysis

Analysis of the test result is by comparing it with the athlete's previous results for this test. It is expected that, with appropriate training between each test, the analysis would indicate an improvement in the strength of the athlete's quadriceps. For muscle balance of your hamstrings & quadriceps your leg curl 1RM should be >80% of your leg extension 1RM weight.

A study by Dohoney et al. (2002)[1] identified the following equations to determine 1-RM for the leg extension test for male athletes:

• 4-6RM : 82.07 + (0.76 x weight) + (5.66 x number of reps)
• 7-10RM : 95.0 + (0.65 x weight) + (8.52 x number of reps)

To determine your 1-RM enter the weight you lifted, the number of repetitions you completed before failure and then select the "Calculate" button. The number of repetitions before failure must lie in the range of 4 to 10 repetitions otherwise the calculated 1-RM will be zero.

 Weight Lbs Kg Repetitions 1-RM

### Target Group

This test is suitable for active individuals but not for those where the test would be contraindicated.

### Reliability

Test reliability refers to the degree to which a test is consistent and stable in measuring what it is intended to measure. Reliability will depend upon how strict the test is conducted and the individual's level of motivation to perform the test. The following link provides a variety of factors that may influence the results and therefore the test reliability.

### Validity

Test validity refers to the degree to which the test actually measures what it claims to measure and the extent to which inferences, conclusions, and decisions made on the basis of test scores are appropriate and meaningful. This test provides a means to monitor the effect of training on the athlete's physical development.

• Minimal equipment required
• Simple to set up and conduct
• The test can be administered by the athlete

• Specialist equipment required
• Assistant required to administer the test

### Referenced Material

1. DOHONEY P., et al. (2002) Prediction of one repetition maximum (1-RM) strength from a 4-6 RM and a 7-10 RM submaximal strength test in healthy young adult males. Journal of Exercise Physiology, 5 (3), p. 54-59