Taking a look at Jacqui Greene Haas’s Dance Anatomy offers great insight into the workings of the psoas muscle in relation to dance-specific movements.
The iliopsoas consists of a group of three muscles. The iliacus, the psoas major, and the psoas minor which are located in the inner part of the abdomen attaching at the bottom of the thoracic spine(T12) and along the lumbar spine(through L4) and pass down over the front of the hip joint, attaching at the top of the femur(thigh bone). The main action of the iliopsoas is to flex the thigh at the hip joint and is key for dancers to lift the knee above 90 degrees and hold the leg at above average heights.
One topic discussed in his work is that of the important iliopsoas muscle. Weakness and tightness of the iliopsoas can result in mis-alignments of the lower back and pelvis, which then affect the legs and stability of the spine.
Since the iliopsoas originates on the anterior aspect of the lower-spine vertebrae, when it is tight it pulls the lower spine resulting in a tilting of the front pelvis forward. Dancing in this anterior pelvic tilt and lower back arch creates an inactivity of the abdominals and adductors.
A weak or tight psoas muscle can "snap" which is a common occurrence in dancers. Snapping hip syndrome occurs when the iliopsoas tendon moves over the head of the femur. This is common in extreme leg movements such as a grand battement or developpe a la seconde. Hass states that “Maintaining strength with turnout throughout an entire range of motion allows the iliopsoas to function in a position that reduces the snapping. Maintaining the flexibility can also help keep the tendon from snapping.”
Here are two exercises to help strengthen and stretch this important muscle!
Try this great psoas stretch:
Here is a great abdominal exercise to help strengthen the psoas:
Hold the Flexistretcher pulled to a slight tension directly over your chest. Keep your arms held in this fixed position. Scissor your legs hitting the top leg into the center of the strap and switch legs. Lower your arms if your leg is unable to reach the strap. Repeat 15-20 times.