You can learn to consciously utilize muscles, like the psoas, that tend to do their own thing, and when you do, it can transform your yoga practice.
The human body is somewhat of a mad scientist. Case in point: the way our muscles work. Some muscles are easy to consciously access, meaning they take direction from us. For example, you can intentionally spread your toes in Tadasana (Mountain Pose). But other muscles work more autonomously, with no apparent direction from the conscious mind—like the muscles working in the background to maintain your posture. These muscles are more difficult to access intentionally because their function involves tasks we have long since relegated to the unconscious mind.
Meet Your Psoas
One such muscle that works mostly in the background (or unconsciously) is the psoas, a core muscle that’s part of the all-important hip flexors and that helps to stabilize the spine. Why does such a big, important muscle have such minor representation in the motor cortex of the brain? It’s all about energy efficiency: We use our psoas to sit down, stand up, and move from lying down to seated; we use it to walk, run, climb, and twist our torso. From a very early age, we use the psoas so much that the brain reassigns it to the level of “background function,” where movement occurs without conscious thought.
From my experience, few people are able to engage their psoas voluntarily (like when you contract your biceps to “make a muscle”). This may be because its actions become habitual during infancy. Yet here’s the good news: You can learn to consciously utilize muscles that tend to do their own thing, and when you do, it can transform your yoga practice. Take Utthita Trikonasana (Extended Triangle Pose) to the right side, for example. When flexing to the right, you could simply use gravity to move your torso over your leg. However, learning to “turn on” your psoas to consciously flex your trunk provides muscular stabilization for your spine, pelvis, and hip that ultimately helps you find the fullest expression of the pose.
Anatomy of the Psoas
To start to awaken your psoas, it helps to know where it is in the body. This muscle originates from the twelfth thoracic vertebra (T12) and the lumbar vertebrae (L1 through L4, with a deep layer originating from L1 through L5), and it runs along either side of the spine, behind the stomach, intestines, and female reproductive organs. From the spine, the psoas continues forward and down, crossing over the front of your sacroiliac joint and joining with the iliacus muscle (which originates on the inside of the pelvis, or the ilium). The psoas and iliacus work together so closely that they’re often referred to as one: the iliopsoas. The iliopsoas then runs over the brim of the pelvis to insert into the lesser trochanter, a knoblike structure on the upper inside of the femur (thighbone).
It’s because the psoas crosses multiple joints that it’s able to move the body in so many ways. For starters, the psoas acts to flex the hip: Contracting the psoas either bends the trunk forward or draws the knee up. If you contract your psoas on one side, it laterally flexes the trunk, as in Extended Triangle Pose. Contract the psoas on both sides, and you’ll be able to tilt the pelvis forward, bringing the thigh and the torso toward each other, as in Paschimottanasana (Seated Forward Bend).
Learn to Access Your Psoas
The process of awakening your psoas begins with learning how to access it at will. You can use certain cues within your yoga poses to do this, even if you’ve never intentionally activated this muscle. Interestingly, what I’ve found with my students and in my own practice is that shortly after you start to engage the psoas intentionally in certain yoga asanas, you will find that the brain starts to engage it unconsciously, even in other poses. It’s as if the brain is saying, “OK, so now we’re using the psoas in yoga poses,” and starts to anticipate using this muscle. I call this “body clairvoyance,” meaning that the unconscious mind sees clearly what to do and then does it automatically. So essentially, by awakening your psoas, you’re trying to learn how to more readily access the muscle’s unconscious actions, ultimately creating the ability to consciously—voluntarily—engage it.
As with any muscle, you want to be able to balance contracting and stretching the psoas. This helps keep the psoas in balance, which goes a long way toward stabilizing the spine and pelvis and preventing lower-back and pelvic pain. The following poses help to awaken the psoas, activating different parts of the muscle so that it’s ultimately easier for the brain to fire it up.
Try them now:3 Poses to Awaken Your Psoas
About Our Writer
Teacher Ray Long, MD, is an orthopedic surgeon in Detroit and the founder of Bandha Yoga, a website and book series dedicated to the anatomy and biomechanics of yoga.