In a previous article I talked about how important it is to stretch the psoas muscle. This can cause many complications including back pain. To recap, most people have tight and shortened psoas muscles. The common activity of sitting causes our psoas to be consistantly shortened for extended periods of time. Also, lower back injuries almost always contribute to a tight psoas. In this circumstance, the psoas will undergo a consistent flexed state to protect an injured lower back. (1)
In addition to the psoas being tight, it is also typically weak at the same time. This creates dysfunction in the muscle. Our brain has trouble controlling the muscle because it has been in a shortened position for so long, thinking the psoas always needs to be flexed. We can stretch endlessly, but if we do not build functionality, then it will easily tighten up again.
Psoas Strength Test
(Modified Sahrmann’s Test (3))
Here is a general way to determine if your psoas is weak:
Standing, grab and pull your knee to your chest as high as you can without leaning backward. You will need to get your thigh well past 90° (in relation to your supporting leg).
Once your knee is close to your chest, release your hands and attempt to keep your leg above 90 degrees for 15 seconds.
Start timing when you release your hands and stop when your thigh drops below 90° (make sure to use a clock on the wall).
If you fail before 15 seconds then you have a weak psoas muscle. Any major body shifts, leans, cramping, or loss of control in the allotted time also results in a failed test. Failure far before 15 seconds shows further weakness. For best accuracy have a fitness professional conduct your test.