Testing You Core: Part 2

Evaluation and Correction of the Lower Back Muscles

We all know that proper strength and endurance of the ‘core’ muscles that protect and surround  your spine is needed to stay healthy and free from back pain.  But very few people actually know how to determine if there muscles are working properly…..

So that is the focus of this four-part article series.  In our previous article we discussed how to test the muscles located on the lateral side of the trunk.  In this article we will review the tests (and corrective exercises that can be used to improve strength of these muscles should you find a problem) of the muscles of the lower back.

Testing the Muscles of the Lower Back

The muscles of the back that we are concerned about today located on either side of your spine and primarily include the Erector Spinae  and Multifi muscle groups.

To test the endurance of these muscles you can perform a test known as the ‘Trunk Extensor Endurance test’.  Here is how you do it:

  • Begin with your your hips and lower body resting on a bed and your upper body handing off the end of the bed.  In this set up position you will have to support your upper body with your arms or elbows (you may need to use a chair in your bed is very high)
  • lift up your arms and try to keep your trunk lifted in the air in line with your lower body.  You will need to have someone help you by holding your feet/lower legs on the bed so you don’t fall forwards)
  • Try to hold this position as long as you can, and record how long you are able to do so and compare it with the normal values reported below.

Note – if  you have pain, or if there is excessive cramping or discomfort in your legs stop the test and record the time.

trunk extensor endurance test

What is Normal?

Studies looking at normal (i.e., healthy people with no back pain) people have found that men can hold the position for about 140 seconds, and women for about 190 seconds (that is not a typo – women were found to have longer endurance times).   If your test falls below this mark it is an indication that you are lacking adequate endurance in the muscle sof your back.  If this is the case, exercises to correct this problem are warranted.

Improving Endurance

The most common, and probably the easiest way to improve endurance in your lower back muscles is through trunk extensor exercises.  This is a variation of the test that is done as an exercise, but as is the case with any other strengthening exercise you want to get the dose right.  In other words, the exercise should be challenging enough the stimulate muscle adaptation, but not so hard as to overload the back to cause injury.


An example of a more advanced exercise to improve strength and endurance of the lower back muscles.

In our office we use a series of exercises of varying degrees of difficulty to retrain this important muscle group.  To learn more about these exercises, simply review the trunk Extensor Endurance tract from our Exercise Library. (here is the link – Trunk Extensor Enduracne Tract).