The iliopsoas muscle is the major flexor of your hip joint. It’s made up of two muscles: the iliacus, the psoas major. These muscles work together to flex your hip, as well as stabilize your hip and ...

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 ...