The iliopsoas muscle is the major flexor of the hip joint, made up of the iliacus and psoas major muscles. Pain in the iliopsoas muscle can be caused by sitting too long, muscle imbalance, overuse, or ...

Gear-obsessed editors choose every product we review. We may earn commission if you buy from a link. How we test gear. This is because a tight iliacus throws off the biomechanics of your hips, which ...