"My lower back had a dull ache and stiffness, particularly after being on my feet a while. Sometimes the pain would run down the backs of my legs and cause extreme tiredness. I'd try to stretch out to get some relief, but it didn't seem to last."
Rolling over of the feet - excess pronation - causes the lower leg to rotate internally. As a result, the pelvis is forced to tilt forward, which can cause an increased curvature of the lower back (see illustration). This is referred to as 'poor body posture'. Especially after standing up-right for longer periods the curvature in back will cause tightness and stiffness of the lower back muscles.
By controlling 'excess pronation' of the feet, orthotics help improve your body posture. Because the feet are now properly aligned, internal rotation of the legs and forward pelvic tilt are greatly reduced, thereby easing low back pain.