Anatomy 101 - the psoas

At our very core, deep within layers of organ and outer muscle, a muscle that is almost as thick as a wrist provides support on each side of the spine. This muscle, the psoas (pronounced so-as), is the only muscle that connects the upper and lower body. It is so vital to our ability to move freely and effectively, and to how we feel, that some researchers have suggested that it should be referred to as an organ of perception. Within the Taoist tradition it is known as the muscle of the soul.

The psoas originates at T12, and each of the lumbar vertebrae, before passing through the pelvis and inserts onto the head of the femur. Along the way it joins the iliacus, with which its action is so intimately connected that they are often referred to as one - the iliapsoas.

The psoas major is the most significant of a group of muscles called the hip flexors, which are responsible for moving the upper and lower body towards one another. However, the psoas is involved with much more than just hip flexion.

It plays a role in stabilising the spine and rotating the hip; it’s the reason why what you do with your legs can affect how your back feels.

If you spend much of your day sitting, or if you cycle or run frequently, it’s quite likely that you’ll have a tight psoas. Stress can also lead to a tight psoas, if you are startled or feel anxious, your psoas will contract. If your psoas is tight you may experience spasms, lower back pain or general imbalance in your spine. A chronically tight psoas can convince your endocrine system that you should prepare for “fight or flight”; this can cause the adrenal glands to produce more adrenalin than you require and play a role in adrenal fatigue, which can leave you feeling exhausted.

So, we all need a long and stretchy psoas, right? Well... yes and no. Our aim should be to build and maintain a toned and long psoas. To begin, we need to develop an understanding of what it feels like when our psoas is working. Then, we should work on contracting the psoas in order to bring blood flow to the area and only then should we lengthen it.

To start with we’ll look at a version of Supta Padangusthasana/Reclining Hand to Big Toe Take a strap. Make a loop in your strap and place it around the ball of your right foot. Lie on your back on the floor with both legs extended, hip width distance apart, toes pointing towards the ceiling or sky. Holding the strap in one or both hands, begin to raise your right leg off the ground. Stop before your leg comes to 90 degrees. At this point, your psoas is holding your leg up against gravity in an isometric contraction. Continue to hold your leg here and if you are finding it quite easy to do so, loosen your grip on the strap until you feel your hip flexors beginning to tire. Notice any desire to arch your back or neck. This will demonstrate how these muscles impact upon the entire length of the spine. Slowly lower your leg, using the strap to control the movement. Repeat on the left side.


In Part I, we explored an isometric contraction but we allowed it to progress to a point where we put a lot of pressure on the psoas to continue to hold the leg up. In this pose, we will seek only to contract the psoas.

Come into Ardha-Navasana/Half Boat, starting by sitting on the tops of the sitting bones, with the feet flat on the floor. Take your index and middle finger into the crease of each knee, with elbows pointing outwards, upper chest open. Maintaining length in your spine, lean your upper body back, making a V shape between your legs and torso. Keep your feet on the ground throughout. After a few breaths and before your feel your spine over arching, return to an upright seated position.

Now we are ready to lengthen and release the psoas.

Practising Virabhadrasana I/Warrior I, is a great way to lengthen the psoas. However, if we want to lengthen the psoas effectively we must pay particular attention to the position of our hips in this pose.

You can choose to step back into Virabhadrasana I/Warrior I  by stepping the left foot back from standing, or by stepping your right foot up towards your hands from down dog, if that’s what you prefer. In either case, ensure that your feet are hip width distance apart and that you can ground down effectively through your back heel.  

Take your hands onto your hips and notice their position. If your back leg has drawn your back hip back towards it, soften your front hip back to rotate your back hip forward. Aim to take your hips level but without forcing your body into the pose. When you feel that your hips are as level as you can comfortably bring them (think about the points of your hips as being like the headlights on a car), inhale and raise your arms, reaching upwards with the palms turned in but keeping your shoulders soft and away from your ears. Draw your tailbone down and think about bringing your tailbone and public bone towards each other. Draw in your lower belly, as if you were zipping up a muscle below your navel where you would zip up your jeans. Maintain the pose for five breaths, or longer if you have the time and energy, then change to the left side, either taking weight on the front foot and stepping the back foot up to meet it or taking a vinyasa and coming back through Adho Mukha Svanasana/Dwonward Facing Dog.

At the conclusion of a sequence including these poses, when you relax into your Savasana/Corpse Pose you will do so with greater ease through your body and a sense of connection to your deepest core.

The majority of Anna’s weekly classes take place within the mental health departments of Dublin hospitals. In addition, Anna teaches pregnancy yoga and post-natal yoga (for mums with babies) at Init Yoga, Ringsend. She also regularly covers classes at The Yoga Room, Ballsbridge.

To contact Anna email or find her on Facebook.