If your psoas muscle was a fellow yoga student, he’d be the kind of guy others might describe as “hard to get to know,” or “Mr. Mysterious.” Hidden deep within the body’s core, the psoas can be difficult to find. But making the effort to befriend this important muscle can help center and ground your asana practice, leading to greater ease of movement.
What yoga teachers commonly refer to as the “psoas” (pronounced SO-uhs) is shorthand for iliopsoas, a pair of muscles—the iliacus and psoas major—that run along both sides of the vertebral column, bridging torso and thighs, joining in a common tendon near the top of each femur bone. Because the muscles of the psoas link the lumbar vertebrae, hipbones, pelvic bowl, and thighbones, they contribute to a number of asanas and movements, from stabilizing the core in standing poses to the sideways bending of the spine in Chrandrasana (Crescent Moon Pose). But the primary action of the psoas is hip flexion, as in Pavana Muktasana (Wind Relieving Pose) or Navasana (Boat Pose).
Daily activities can shorten and weaken the psoas: slouching, sleeping in the fetal position or sitting for long hours—especially in a low-slung car, when the knees are higher than the hip joints. Poor body mechanics and injuries may lead to imbalances—if the psoas becomes more contracted on one side of the vertebral column than on the other, it can even pull the spine into a lateral curve (e.g. functional scoliosis). The hormones and nerve signals from stress and fear responses can also trigger the psoas—the muscle we use to lift the knees and run or to curl up and protect ourselves when feeling defensive.
From a yogic perspective, the psoas can be a storehouse of samskaras—conditioned patterns, old traumas, hidden agendas. The iliopsoas muscles form a triangle, its apex at the twelfth thoracic vertebra (where the diaphragm also attaches) and its base at bottom of the hips. This triangle is the territory of the first three chakras or energy centers, which relate to basic human needs, instincts and impulses.
Located deep within the belly area, the psoas major is difficult to palpate. To explore your left psoas major, lie down on the floor with knees bent. Breathe and relax, resting the fingertips of your left hand midway along an imaginary diagonal line between the navel and the ASIS (the bony prominence at the front of your hip). On an exhalation, gently press your fingers into the abdomen. Lift your left foot off the floor to bring the knee an inch or two closer (hip flexion). Can you feel the psoas contracting under your fingers?
Tight psoas muscles can be either weak (in desk jockeys) or strong (in runners). In either case, shortened hip flexors tend to pull the front of the pelvis down in poses like Trikonasana or Virabhadrasana II, which in turn compresses the lumbar area. Many asanas involve either hip flexion (Utkatasana, for example) or extension (Ustrasana, Supta Virasana, etc.), respectively strengthening or lengthening the psoas. Lunges do both. But to lengthen the psoas (or any muscle) effectively, it’s important to relax it first. Here’s how:
Lie down in Shavasana with knees bent. Easy, right? Mmm, not really. (Remember Mr. Mysterious?) Can you sense how gravity softens the psoas muscles, helping them release toward the floor? This may require your sharpest powers of internal awareness, your skills at self-cuing, and your ability to visualize something you can’t see with your eyes. Doing this, you learn how to practice asana from the inside out.
To put it another way, as you fine-tune your awareness of the psoas (or your breath or your feet or … you get the picture!), you are taking your practice to a more advanced level.
Can you remember an asana or instruction or moment that inspired your deeper journey into yoga?