In terms of muscle function and attachment, the hips and the low back are interestingly and inseparably interwoven. One affects the other and many muscles span both structures. In addition, the muscular system works in polyarticular muscle chains to move the body, as opposed to independently isolating and contracting one muscle at a time.

Hips have strong muscles intended to be used as “prime movers” such as the glutes and hamstrings, and the hip is a ball-and-socket joint designed for motion. In contrast, the vertebrae of the low back are primarily set up for stability and the transfer of forces.

Lumbar vertebrae do not have the range of motion of a ball-and-socket joint such as the hip. However, if the hip muscles are stuck or cannot function harmoniously, the low back is likely to have to work too hard.

There does need to be some low-back motion in terms of lateral shifting and rotation for gait, but if you lack proper motion in your hips, and you are primarily using back muscles to propel yourself through your day, you’d rather go home and sit in your lounge chair instead of going out and have a fun night on the town.

Ideally, stabilizer muscle activation and endurance (primarily obliques and transverse abdominus) are working to hold your torso in a neutral position, creating a pleasant, pain-free disposition, while larger hip muscles propel you where you want to go, with a smooth, graceful flow.

A neutral torso position should enable relatively equal muscle activation/contraction all around your abdominal wall: back, front, and sides.

The psoas muscle, commonly referred to as a hip flexor muscle (brings your knee up towards your chest), might initially not be of much interest. However, this muscle originates on your lumbar spine, giving a direct connection to pull on, compress, or twist your low back. There are some interesting theories that a healthy psoas acts more as a lumbar stabilizer and the iliacus is the primary hip flexor.

But getting back to psoas… If this muscle is stuck in a shortened or contracted state, perhaps from you being in a prolonged static seated position (driving, flying, working at the computer, etc.), when you stand up, the muscle’s lack of lengthening can pull on the attachments to your lumbar vertebrae, restricting your ability to extend into upright posture and keeping your lumbar spine pulled forward. This is a common culprit that can influence low back pain. Releasing the hip flexors with targeted bodywork such as ART can be powerful at restoring hip motion and taking pressure off the low back.