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Tight Muscles & SI Joint Pain


My client has a re-occurring problem with pain in the lower back around the SI joint. His hamstrings and hip flexors as well as the back are very tight, usually in the morning, and he has a desk job. His doctor’s referral suggests a sway back posture, yet there is no accentuated anterior tilt. This is being referred to a neurological specialist as he has a "bubble-wrap" like effect at the medial aspect of the hamstrings in the region between the semi-membrinosus/tendinosus or perhaps closer to the interaction with the adductors. In regards to his training, he has very good balance and movement patterns. He can stand on a Swiss ball as well as squat on each leg individually below 90 degrees easily. Recently, the pain has been exaggerated by deadlifts, but it can be relieved by performing them on one leg with the spine in full flexion. He is seeing a physio who suggests that it is the piriformis that is very tight and aggravating the sciatic nerve. The situation is eased when the glutes and in particular the piriformis are stretched. However, I am a little skeptical of the work of the physio as the sessions don't appear to be attacking the heart of the problem. I would be extremely grateful for any help you could provide.


One of the key factors we need to remember as trainers is that it is not in the scope of our practice to diagnose or treat injuries. We need to leave that to the medical specialists. In the case of your client, it is important to understand the role of the muscle system and how it relates to injuries. As trainers, if we do not have a thorough understanding of biomechanics and muscle function, then we may be placing ourselves at risk liability-wise each time we set clients such as these on exercise programs. By understanding the role of the muscular system and its relationship to injury, trainers will know how the body handles the forces being placed on it, in both a healthy and an unhealthy situation.

In a case such as this, you note that your client has limited ROM in his hips and lower back area. Since, as trainers, we cannot treat the injury, the tightness becomes our primary area of concern. We have to question why these tissues have tightened up. Typically, it is due to a protective mechanism where the body is protecting itself from moving into positions of instability. Since stretching has not seemed to work, the body seems to be saying, "fix the problem!" It would seem from here that the instability component needs to be addressed. Instability from the muscular system is due to a lack of neural integrity of the muscles that support the joint. When muscles are not getting proper input from the CNS, they typically lose the capability to move the joint though it’s full ROM. This causes the opposite muscles to tighten up. Therefore, the hamstring tightness can be secondary to lack of contractile capabilities of the hip flexors and quadriceps muscles. These muscles would need to be "jumpstarted" in order for the tight muscles to relax, since when the body senses stability, it no longer feels the need to tighten up. In order to jumpstart the muscles and increase contractile capabilities, you would want to have the client move into the restricted range of motion, then perform six very low intensity isometric contractions, pushing further into the position of restriction. Each contraction should be held for six seconds, noting that you would never have them do this if there is pain or discomfort. Performing these isometric contractions reconnects the input coming from the CNS to the muscles, which in turn gives the body a new sense of stability and allows the tight muscles to relax. Stability is the key to optimal movement.

This isometric process for jumpstarting muscles is the foundation to Muscle Activation Techniques (MAT). For more information on MAT and the concepts discussed here, go to