The psoas is truly a holistic muscle integrating body, mind, emotion, and spirit. Both unique and complex, it defies being easily classified. Bridging multiple functions, the juicy tenderloin challenges all artificial boundaries that attempt to compartmentalize our human experience.
The iliopsoas complex consists of two separate, but interacting muscles: the psoas (pronounced so-as) and the iliacus. The psoas spans from the solar plexus to the inner leg. The iliacus fans up and opens inside the pelvic basin and together the psoas and iliacus share a tendon that intrinsically links the two muscles together and secures their profound interrelationship. The psoas reverberates within the iliacus and in turn what manifests within the iliacus is reflected within the psoas.
The psoas is the largest core muscle and grows out of each side of the spinal midline vertebra. Originating at the twelfth thoracic (T12), the psoas continues emerging out of the five lumbar vertebrae to flow through the pelvic basin, surface over the hip socket, and grows back into the lesser trochanter of the femur bones.
To locate T12, place the hands on the last rib and follow them around to the back of the spine; this vertebra is T12. The psoas grows out from the sides toward the front of each vertebra flowing diagonally through the core. Place the hands over the solar plexus area at T12 to sense it at its deepest level. Centered along the midline, the psoas surfaces only as it lengthens over each hip socket.
To locate the hip sockets, touch the front of the pubic bone, sliding fingers up at an outward angle (approximately two inches) to the hollow area on each side of the front of the pelvis. Crossing over the hip sockets, the psoas dips back, much like the strings flowing over the bridge of a violin, toward the upper area of the inner thighs.
The psoas grows into a small knobby protrusion, called the lesser trochanter of the upper femur (leg bone). To locate the lesser trochanter, place your fingers on the large knob on the outside of the thigh/hip. This knob is the greater trochanter and is commonly thought of as the hipbone, but it is actually the upper angled protrusion of the femur head, not the actual head of the femur ball. The ball of the femur sits in a cup formed by the ilium, which is located at the hip socket in the front of the pelvis. Here at the actual pelvic socket joint is where the skeletal trunk ends and the leg begins. All flexion, extension, abduction, adduction, and, most importantly, rotational movement occurs at this junction. It is here at the hip socket that the cardinal planes of gravity express themselves for optimal foot dynamics. Now draw an imaginary line from the greater trochanter toward the midline-groin area. On the inner leg just below the groin and toward the back (posterior) of the leg is where the tendons of both the psoas and iliacus muscles merge into and out of the lesser trochanter.
The psoas connects the spine to the legs and is embedded within the deepest layer of connective tissue (in the sympathetic neuro-core along with the spinal cord and kidneys). Although the psoas has been thought to serve the spine like a guide wire creating stabilization, its main job is actually to convey messages concerning subtle changes in weight, location, and safety. When functional, the psoas is in intricately involved in all spinal movement and acts as a pendulum allowing for free swing of the leg while walking. The 360-degree expression of the psoas unifies upper and lower, front to back, and side to side for whole-body coherency.
Strategically positioned where a diversity of systems and rhythms transpire, the emergence of the psoas from deep within the midline has an intimate relationship with the abdominal viscera and offers a bridge between the skeletal, arterial, lymphatic, and organ functions. Messaging both structural support and organ rhythms, the psoas communicates subtle shifts and changes in structural, neurological, chemical, and energetic dynamics.
The psoas bridges the brain in the belly (the enteric nervous system) as well as the central and autonomic nervous systems. The large nerve ganglia, located within the belly core, travels to the digestive and reproductive organs passing over, embedding into, and through the psoas. Serving as messenger of the midline, the psoas translates and transmits all expressions of safety, harmony, and integrity, signaling whether we are centered and congruent or encumbered and vulnerable.
The psoas forms a diagonal muscular shelf behind upper and lower abdominal organs and, with its fluid dynamic expression, massages both viscera and spine. Its pendulum motion plays a vibrant role in stimulating fluids by providing an internal massaging motion with every walking step. But only when it is juicy does the supple, hydrating motion of the psoas continuously nourish the core.
The vitality of the psoas profoundly influences every aspect of our health. When the psoas is called upon to support structural misalignment, its suppleness is curtailed and over time its delicate tissue dries and shrinks. If consistently used as a structural or emotional support, the expressiveness of the psoas will diminish.
Two nerve innervations go to the psoas: the psoas major and minor at L1 and L2, and the psoas major and iliacus muscle at L3 and L4. Sensing the lower psoas crossing over the hip socket articulates the leg from the trunk, sexual expression, and pelvic movement. Sensing the upper psoas articulates the expression of the diaphragm and the integral gut emotions of integrity, courage, and the capacity to self-manifest. The healthy psoas, rather than being segmented at each individual joint attachment, functions as one integrated and coherent whole.
Biomechanics classifies the psoas as a hip flexor; however, the psoas is an evolving tissue and its form and function has shifted over time. From being a major flexor to a supple guide wire, the healthy psoas no longer behaves as a flexor, but as a neutral, multidimensional transmitter. No longer as massive as a primate’s psoas, the human psoas does not function as muscle, but as the sentinel of the midline. Defined as an eccentric-contracting muscle, the psoas “shortens” only when in inverted positions. In upright walking, it lengthens back along the spine to release a neutral pendulum motion that provides the abdominal core with both its integrity and its freedom. A leg that moves from a supple psoas kicks, extends, flexes, rotates, adducts, and abducts without pulling on the core.
The upper psoas and the diaphragm (a jelly fish-like dome structure) are intimately involved at the T12 level. The diaphragm’s undulating expression, billowing open and closed with attachments emerging from deep within the core at the third and fourth lumbar spine, is supported by a responsive, supple psoas. Forming the floor of the thoracic and the roof of the abdominal cavity, with the heart and lungs above and the stomach, spleen, liver, and kidneys below, the voluminous diaphragm, along with the juicy psoas, embody the depth and volume of core expression. Affecting each other’s motion and rhythm, the diaphragm and psoas dance the dance of breath with a heartfelt passion.
Any restriction in the upper psoas will impede diaphragmatic breathing, compressing in and down, creating hyperextension in the lumbar spine. By limiting diaphragmatic expression, a constricted psoas shifts the diaphragm forward, limiting its range of motion and three-dimensional capacity.
The esophagus, which penetrates through the diaphragm to the stomach, and the major aorta, descending behind the diaphragm on its downward movement into the cavity of the core, are dependent upon a supple psoas for unimpeded functioning. If the psoas is constricted and dry due to abuse, misuse, or overuse, the spaciousness within the abdominal core is minimized. It is the constricted upper psoas that, by pushing on the esophagus, potentially contributes to hernias and digestive problems and may curtail blood flow to the pelvis, legs, and feet. Only when the diaphragm and psoas cohabit harmoniously can their dance invigorate and nourish the animated core.
The outward rotator muscles counterbalance both psoas and iliacus muscles. This balance creates a base for the undulating pelvis and the free swing of the legs. Ignited by the oscillation of the heart and breath, walking pulsates through the psoas lumbar plexus and is a catalyst for leg, anal, and sexual functions.
When the iliacus fans open, the six outward rotators support the integral tone of the pelvis. These small but powerful muscles maintain integrity at both the hip and sacral joints. Whether the psoas and iliacus (iliopsoas complex) are constricted due to poor ergonomics or emotional repression, once the outward rotators lose their tone core integrity will be disrupted.
The erector spinae muscles also counterbalance the psoas and, when toned, are reflected in a released psoas and open iliacus. Just as the psoas releases in a downward motion, the muscles along the back of the spine provide an upward motion supporting the concurrence of the spine and head. When the erector spinae are toned, these muscles not only support the release and lengthening of the psoas, but also expand the expanding iliacus and sternocleidomastoid muscle (SCM). Located on each side of the neck, the SCM emerges out of the sternum and clavicles to move diagonally up toward the mastoid processes behind each ear. Functioning like a secondary psoas, the SCM opens the throat. The full expression of the SCM is witnessed in the sympathetic fear response, primitive reflexes (startle), and full-body orgasm. Intimately close to the vagus and jugular nerves, this secondary psoas moves upward, freeing the head to align with the torso and fully opening the midline from anus to mouth.
The multifidus muscle, like the psoas, is a very misunderstood tissue. Both are intimate with the processes of the vertebrae. The multifidus located on the back of the midline and the psoas located on the front of the midline support dynamic spinal movement. From sacrum to axis, the innate tone of the multifidus provides support for the spine to work effectively and is vital for preventing vertebrae degeneration. Small, round, and narrow, the multifidus lengthens in spinal flexion (fetal-C curl) and therefore increases its strength when standing neutral. When the psoas and multifidus, both intrinsic muscles, are fully understood, the use of the primal movements (arcing and curling) are recognized as beneficial, whereas muscular corseting of the core and/or fusion of the spinal vertebrae are detrimental to spinal health.
Often associated with core strength, the abdominal muscles provide a secondary level of balance within the core. When the iliopsoas complex is constricted and the tissue shortens, it pulls and narrows the pelvis forward and down and the abdominal muscles lose tone. Post-pregnancy, poor ergonomics, and intestinal health are also contributors. Although a functional psoas and iliacus help to establish healthy abdominal function, abdominal tone alone does not release the iliopsoas complex. Overdeveloped or surgically tucked abdominal muscles prohibit the psoas from fully functioning and therefore, when corseted, these muscles impede upon the ability to have a juicy psoas. Good abdominal tone is better found by awakening neurology in the tissue, establishing neutrality in the core, and hydrating along the back and sides of the body. Toning and lengthening muscles, specifically the hamstrings, which merge into the tuberosities (sits bones), play an important role in maintaining a healthy abdominal and pelvic tone.
Occurring simultaneously, the iliacus and the abdominals both naturally respond to the upward flow of rebound, whereas the psoas deep within the core continuously flows down toward the Earth. Rather than use abdominal corseting to establish core strength, real core power comes from reestablishing the core’s full expression of primal movement with healthy abdominals undulating open and closed similar to an accordion. By distinguishing the interaction between the different levels of movement within the core, we can harness a source of power much greater than isolating any single muscle group.
The iliacus muscle, partner with the psoas, influences range of motion and stability within the hip sockets, overall integrity of the pelvic basin, and the maximum rotational freedom of leg movement. When a restricted psoas shortens, tipping the pelvic basin forward, it limits internal space and constricts the function of the iliacus muscle.
Lining the internal ilium, each iliacus muscle fans open, creating a container for embracing and supporting balanced organ suspension. The iliacus stabilizes the sacroiliac joints (SI joints) and counterbalances the gluteus maximus muscles (buttocks), helping to maintain pelvic integrity.
Men’s and women’s bladders and sexual health rely on the expansive uplift of the iliacus. By creating a sense of both depth and lift, the iliacus offers volume for the suspension of fluid organs within the centered pelvis. Prostate health for a man and the star suspension of a woman’s uterus depend upon healthy iliacus muscles. However, when the iliacus is closed tight, it pulls on the pelvic crests narrowing the width of the pelvic basin and displacing its spatial position on either side of the sacrum. This results in compression in the hip socket, pressure upon pelvic organs, and destabilization of the SI joints.
From a workshop report:
A woman noted how releasing and fanning open the iliacus muscle soothed and calmed her. She related the sensations to an image of a cat by explaining that usually she felt like a cat whose tail was up and its fur on end, bristling and irritated. Releasing her iliacus muscles centered her pelvis and by stabilizing her SI joints, her blossoming iliacus muscles calmed her entire nervous system.
As above, so below is reflected in the iliacus muscle because it exemplifies that a tipped narrow pelvic basin will affect the low back, neck, and shoulder girdle. Compensating for the narrow flexed pelvis, upper structural integrity alters in an attempt to maintain balance. The suscapularis muscles (lining the inside of the scapula) also fan open, mirroring the breadth of the iliacus muscles.
The latissimus dorsi (Latin for broadest muscle of the back) has a unique relationship with the psoas; like lovers, they complement each other. Yet like all couples, they are completely different and unique. The psoas is central to the core, while the “lat” expands laterally up and away from the core. The psoas is very deep and the lat is very superficial. The psoas connects spine to leg while the lat connects spine and pelvis to arm. The psoas takes us into our core; the lat takes us out toward the world. The psoas is all about core integrity; the lat is all about reaching out into the world and bringing the world back to the core. The tango they dance together is a beautiful balance of yin and yang, male and female, personal and communal energies, and interwoven dynamics. The freedom of one depends upon the freedom of the other; flowing in harmony together, they support wholeness and congruent behavior.
Passing over the ball-and-socket joint, the iliopsoas complex, for better or worse, influences all rotational hip movement. Depending upon the length and suppleness of the iliopsoas, the hip socket is either free to move or is limited, congested, and lacking proprioception.
Hip socket problems are widespread today. Abrasive wear and tear on the joints from lack of resilient walking surfaces such as cement, nutritional leaching, and nominal lubricating movement create a multitude of problems. To have functional hip sockets we need increased proprioceptive articulation because when it comes to hip sockets it truly is a use it or lose it proposition. Whether dysfunctional hip sockets are a result of a constricted psoas or from dominating leg muscles, any lack of articulation at the ball and socket jeopardizes hip socket health and vitally, disrupts pelvic stability at the SI joints, and puts spinal health at risk. Regaining a supple iliopsoas complex is the first and most important step in reestablishing and maintaining healthy hip sockets.
Inborn, primitive survival ignites the fight, flight, or freeze response. Fear is a healthy survival response helping us sense danger and respond appropriately. When in danger, it is our psoas that notifies us to pay close attention, readying us to quickly move away, stand our ground, or take cover. In sync with large extensor muscles, the psoas prepares us for running or kicking and, in accordance with large flexor muscles, protects us by curling and rolling. Being somatically conscious of these primitive responses offers cues for responding to current life situations, which when not life-affirming may demand that we stand our ground and voice our needs. Recognizing primitive responses helps us make wise decisions in support of ourselves.
The psoas, a part of these instinctive responses, prepares us. Whether it is falling in love or propulsion through space, the dynamics of falling is a process of deep surrender (different from collapse) within the core. People who experience falling off roofs or out of trees explain that they find themselves, upon landing, rolled up in a ball in a fetal curl (fetal-C). Rolling into fetal-C protects vital organs and the soft vulnerable parts of our body while providing resiliency to the spine, which helps us sustain the blow or fall.
Another primitive instinctive response stimulated by proprioception within the inner ear is startle (or the Moro reflex). Elicited by loud noises or quick shifts in spatial movement, a newborn infant arches back in what is preparation for grabbing hold, calling out for help, reaching, and, if all else fails, falling and rolling into a fetal curl.
Working intentionally with our fear responses helps us access a healthy psoas. Our inner sense of integrity and harmony depend upon them. It is by exploring fetal-C curl and startle arc that we can sense how powerful the primitive midline truly is. Instinctive responses can save our lives: jumping back from an oncoming car, having the adrenaline to run for your life, or to lift the truck off the dog are all vital for survival. However, by working with core awareness, we hone our capacity to be alert, responsive, and undefended rather than simply having knee-jerk reactions. We develop our ability to consciously choose how we wish to respond. Reestablishing a supple psoas is fertile soil for growing a responsive, rather than reactive, openhearted and inclusive consciousness.
Taoist healers refer to the psoas as the muscle of the soul. Profoundly expressive of our emotions, the psoas is a grounding force that allows us to receive and transmit subtle energy moving through the midline.
According to Oriental philosophy the expression of life is energetic and its qualities may be seen and expressed in the basic elements of earth, water, wood, fire, and air.
The wood element is associated with liver energy that flows down through the hip sockets into the large toe. The psoas follows this energetic flow through the trunk and into the hip socket. Consciously sensing and releasing the lower psoas often elicits not only feelings of fear, but also of anger. Anger and creativity are the dominant emotions associated with wood energy. Wood energy excites and moves us to make changes in our life. Similar green wood growing, liver energy is creative, strong, and powerful.
One may feel a strong desire to kick, stomp, or shake the legs when releasing this energy around the lower psoas, specifically around the hip sockets. In the safety and privacy of one’s home, throwing a child-like tantrum, arms and legs moving up and down in their sockets, feet and hands stomping the ground or kicking the air, can not only feel wonderful, but also can help pent-up energy recirculate. It is valuable to simply stay with the sensation, letting the feelings move as the energy flows down through the genitals and anus, into the legs, and feet toward the Earth.
In a workshop report:
One gentleman attending a workshop had immense stiffness in his upper body. The rib cage and shoulder girdle appeared glued together and hard like rock. His lower body was soft and flaccid. He explained that no one had been able to help him in his quest to release his upper-body tension. Every time his upper body was adjusted or massaged, the tension and holding quickly returned. I asked him if he expressed anger as a child. He said “of course not!” Having never been given permission to throw a tantrum, I suggested he stomp his feet. Lying on his back on the floor he pounded his feet and hands and made facial grimaces. When he stood up he was pleasantly surprised to find his clavicles and shoulder girdle had softened while he felt more grounded through his legs and feet.
The gall bladder meridian, the corresponding meridian to liver energy, is also within the domain of the psoas. It flows up and around the back of the hip socket at the location of the outward rotators on its way to the head. Gall bladder is associated with the ability to make good decisions. Green with envy or having a lot of gall is associated with gall bladder, or wood energy. Together liver and gall bladder govern the ligaments and tendons. Lunges, which potentially lengthen the psoas, positively affect the liver and gall bladder energy.
Another workshop participant complained of soreness in the area of his greater trochanter. An easygoing man, he felt confused as to why there was so much pain around his hips. As he released his psoas he became aware of not only how flaccid his outward rotators were, but also of a particular memory. He remembered that his mother had used anal suppositories beginning at age 6 months as a potty training tool. Working with hip flexor explorations, he began to assert himself and establish his personal boundaries as his iliacus muscle expanded and his outward rotators regained tone.
Self-will, self-actualization, courage, survival, and fear are all qualities associated with the element of water. The water element is revealed as kidney energy and expressed within the solar plexus where the psoas and kidney organs reside. The element of water is thought to govern bones and blood and is associated with all primordial life and our most powerful desire to self-actualize.
From this perspective, it is understandable how the misuse of the upper psoas can express our willfulness. When we want something very much—a higher kick, a firmer body, a longer range of motion—anchoring at the upper psoas may seem like the only way to force whatever we want into being. But when one part of the body is locked in determination, other parts pay the price. Anchoring the upper psoas because of its close proximity to the kidneys may be detrimental to our adrenal health. As part of the fight, flight, or freeze response, the psoas is associated with adrenal depletion, exhaustion, and lowered immune response. Nourishing the adrenals helps heal an injured or dysfunctional psoas and, vice versa, a supple psoas replenishes the adrenals through its massaging movement. An anchored upper psoas also affects the breath and quality of feeling throughout the lungs and heart. A tight upper psoas will block our hearts from emotionally opening and expressing our love and vulnerability.
By keeping our feelings under control, the tight upper psoas can stop us from impulsive sensations felt within the belly core. Getting a grip on our feelings involves abdominal and upper psoas tension. Muscular tension holds feelings in check by blocking the diaphragm’s range of motion and limiting sensory awareness. However, such tension ultimately fragments the psoas muscle’s fluid wholeness. For maturation to occur, it’s vital that both the upper and lower psoas function as one complete and integrated expression.
The kidney meridian energetically connects the upper psoas to the foot. Right in front of the arch of the foot is a major kidney point called the well of life, or bubbling spring that is associated with our ability to draw nourishment from the Earth. Our kidney meridian and the corresponding bladder meridian that flows along the back of the body are associated with protection and defensiveness. The water element, expressed by the kidney and bladder meridians, is also associated with the orifices, such as the genitals and the anus, and thus affects sexual and bladder health, menstruation, and orgasmic response.
The psoas emerges out of what Qi Gong and the Chinese energetics refer to as the conception and governing channels—the front of the midline being the conception vessel and the back of the midline being the governing vessel. Referred to as the psychic or miraculous meridians, the governing vessel is responsible for yang energy expressed as an internal fire and the conception vessel is expressive of the yin energy responsible for nourishment; both play an essential role in the overall circulation of energy and emotional balance of our self-regulating system. The conception or governing channel is expressive of sexual energy. It is the psoas that undulates while experiencing a full-body orgasm. The midline in its primitive response moves through a wave-like motion as it overflows us with pleasure.
Emotional muscular tension is a form of armoring that exhausts the potential of the psoas. Stretched ligaments, tendinitis, sciatica, dislocations, compressed disc, low back, knee, ankle, and hip problems may all be traced to imbalances reflected in an exhausted, overused (or misused) psoas.
When overused, misused, or abused (ignoring its signals), the psoas eventually loses suppleness and begins to dry and eventually shrink. When the pelvis is structurally unable to transfer weight, the psoas (overused) is called upon to provide support. Conversely, chronic fear engages the psoas (misused) and compromises pelvic stability. A spasmodic psoas torques the pelvic basin. A whirlwind of emotional energy damned up will cause both a muscular and energetic logjam. Undigested feelings of fear or anger can and will fragment somatic wholeness.
When engaged as a structural support, the psoas signals a continual low-grade anxiety. Behaving as if in continual survival mode (i.e., living a fast-paced life) signals the sympathetic nervous system and therefore being overstressed further depletes the adrenals and immune system. Continually being in a defensive posture and on guard maintains compensatory armoring. Skeletal instability contributes to a need for more and more muscular involvement. It is by regaining a supple psoas and centered pelvis that harmony is reestablished within the core, which helps to free the outer musculature to regain motility. Similar to a seed that no longer needs its outer shell for protection, our vital force breaks through and flourishes.
Early reflexes appear, dissolve, and then reappear as functional movement. Walking, for example, is seen as an early tracking motion in young infants that disappears and then reappears months later when the toddler begins to walk. It is the dynamic spinal midline, oscillating heart, and supple psoas that allows for the smooth propulsion forward through space.
Early walking begins with a symmetrical falling and catching motion, which over time matures into the asymmetrical psoas and arm pendulum motion. As weight shifts forward through the dynamic force of an undulating spinal midline, a rebounding or ground force reaction balances the falling response. The responsive psoas releases a pendulum motion from spine to leg. As the weight falls, a counter point aligns and organizes ground and space. This rebound action, through ground and foot, may be sensed as energy moving up through all the bones, lifting the sternum as it travels up through the skull. As walking patterns become more sophisticated, movement of the spine and psoas work together taking on a dynamic spiral propulsion and pendulum motion propeling the body into asymmetrical (opposite arm and leg) forward movement. As movement matures, there is a definition of separate but integrated cross-patterning movements with each psoas muscle functioning separately yet seamlessly integrated.
Tender and valued as the choicest cut of animal meat, the psoas muscle is the filet mignon. What makes this cut of meat so prized as a delicate food is its juicy tenderness. The human psoas has no viable fascia in the upper muscle and very little in the lower psoas as it passes over the hip socket. This is reason alone not to have your psoas palpated by deep massage techniques or invasive myofascia manipulations. Attempts to physically palpate the very deep psoas have resulted in ruptured arteries, intestinal hernias, bruising of the psoas, and aggravated nerve damage.
Attempting to manually release the psoas muscle through manipulative techniques also goes against the very nature of the muscle’s instinctive behavior. Invasive techniques (no matter the reasons for performing them) register an instinctive fear response when safety is compromised. In other words, the core reacts to the invasiveness instinctively even if the person, either practitioner or client, can rationalize reasons to palpate. Going against our instinctive responses results in a form of dissociative thinking that does not ultimately bring coherent resolution. Instead of manually manipulating the psoas, it is more beneficial to understand its message and differentiate between what is simply a reaction in our system with what is a genuine resolution. No one else can manually release another person’s psoas muscle and achieve resolution. At best, a manual therapist can encourage and support resolution using a variety of skilled techniques, hold space for the natural healing process to unfold, and educate the client. Reconnecting with our own psoas can begin anytime, anywhere, and quickly achieve resolution of the fear response, trauma, and disrupted proprioception. Constructive rest provides an excellent starting point.
The constructive rest position (CRP) is a position in which gravity naturally releases the iliopsoas complex. It is a safe position for exploring fear as well as all other emotions. Should one feel restless or fearful while in the CRP, rest assured that it is not the position itself or the present situation that is creating the sense of danger. The feeling of fear may actually be old conditioning surfacing as the tissue begins to release.
Getting in touch with our sensations, feelings, and thoughts while being present (observing the quality of light, sounds, smells, taste, and sense of contact) helps to evolve the nerve pathways and awaken fresh somatic awareness benefiting not only our capacity to survive, but also our capacity to thrive.
By its very nature, the psoas muscle defies easy classification. Properly engaged, the psoas provides resiliency, strength, and subtle balance resonating wholeness on every level of our being. Serving as messenger of the midline, the psoas integrates our emotional and spiritual worlds with the ordinary, the practical, and the mundane.