Many people seek out yoga and physical therapy in the hopes of releasing the iliopsoas (a composite muscle consisting of the psoas and the iliacus). Iliopsoas tightness can be caused by a sedentary lifestyle: Similar to the hamstrings, this muscle is particularly susceptible to the negative effects of prolonged sitting. The iliopsoas also tightens in response to activities (and yoga poses) that require the muscle’s recurrent contraction, during sports that work the legs or core by requiring repeated hip or spinal flexion.
WHERE THE ILIOPSOAS IS, AND WHAT IT DOES
The iliopsoas is the only muscle that connects the legs to the back. Beginning at the lower back, the psoas major runs through the pelvis bowl, where it picks up the iliacus, just inside the ilium. (The psoas minor, which arises from the lumbar spine, runs alongside the psoas major, and inserts at the top of the pubic arch, typically attracts less attention—not only because it is smaller and weaker than the psoas major, but also because it is only present in roughly a quarter of all people.)
The combined psoas major and iliacus then join to the inner top part of the femur (thighbone), at a rounded protuberance known as the lesser trochanter. The iliopsoas supports the lower back and aids in posture, but its primary function is to flex the hip, which it does more effectively than any other hip flexor (which include the rectus femoris, sartorius, and tensor fasciae latae) by contracting to bring the thighs nearer the spine. It also helps to flex the spine, contracting to move the spine nearer to the thighs.
To fully address the iliopsoas, special attention should be paid to hip extension (movement of the hip joint when standing and raising the leg back). Here are 2 yoga poses you can incorporate into your at-home practice to target psoas length.
Bhujangasana (Cobra Pose)
Lie on your stomach and place your palms in line with your lower ribcage. Keep your stomach in and your hips neutral as you lift your upper body off the floor. Keep your elbows tight at your sides and your shoulders relaxed. Create a movement in your palms that pushes your body forward. Focus on feeling an opening in the front of your hips vs a compression in your lumbar spine. Avoid any pain on the lower back.
Virabhadrasana (Warrior 1)
Stand and step your right foot forward. Step your left foot back and angle it out at 45 degrees. Keep your feet in line with your hips. Bend your front knee and keep your back knee straight. Concentrate on keeping your hips and shoulders square toward the top of the mat as you reach your fingertips overhead. As you sink into the pose, feel your lower abdomen tighten and your left psoas stretch. Repeat on both sides.
Anjaneyasana (Low Lung Pose)
Kneel and then step your right foot forward. Walk the left knee back, keeping the weight off your kneecap, and contract your abdomen to create a neutral lumbar spine. Hold this pose, sinking into your hips and stretching your left psoas. Avoid any pain on the lower back. Repeat on both sides.