What Does the Psoas Muscle Actually Do?

The psoas muscle may not get much attention, but it plays a major role in how your body moves and feels every day.

Located deep in the core, the psoas connects your lower spine to your upper leg. Its main job is hip flexion — meaning it helps lift your leg when you walk, run, climb stairs, or stand up.

But it does much more than that.

The psoas also helps:

• stabilize the lower back,
• support posture,
• and assist with core balance and movement.

Because it connects directly to the lumbar spine, a tight or weak psoas can contribute to:

• lower back pain,
• tight hips,
• poor posture,
• and stiffness after sitting for long periods.

This is why people with desk jobs often feel tightness in the hips and lower back. Sitting keeps the psoas in a shortened position for hours at a time.

Keeping the psoas healthy usually involves:

• regular movement,
• walking,
• mobility work,
• glute strengthening,
• and avoiding excessive sitting.

In short, the psoas is one of the body’s key “bridge” muscles between the upper and lower body — and when it’s functioning well, your entire body tends to move better.