How the iliopsoas is involved in Action Response posture
The action response describes a postural reflex that occurs automatically every time we want to get up and go. We arch our back, lift our head, pull our shoulders back, stick out our chests, straighten our knees, and rotate our legs outward.
Our action response is also triggered by eustress, or positive stress, such as giving a presentation or meeting our new boss. Whenever we want to make a good impression and be on our game, we instinctively contract the extensor muscles of our back so that we stand up straight, look taller, and appear to be confident. This posture prepares us both physically and psychologically for action.
If you tend toward action response posture, your pelvis is likely tilted forward, or anteriorly, as shown in the photos below. This creates an exaggerated arch in the lower back, referred to as hyperlordosis.
You may initially adopt this posture as a result of positive stress, athletic training, or a repetitive activity. Then over time, as your pelvis is held in anterior tilt, the iliopsoas will gradually become tighter as a result of being held in a shortened state. Once the iliopsoas is tight, it can help to keep you stuck in this posture.
The reverse can occur as well. Your iliopsoas may become tight as a result of repeated hip flexion, such as occurs with running, kicking, or even sitting down for long periods of time. If you have chronic tension in your hip flexors and you’re standing upright, your nervous system has two options to allow your hip flexors to stay in a shortened state:
1. It can allow the pelvis to tip forward, as occurs in action response posture.
2. It can allow the pelvis to stay upright or even tilted backward, but must flex (bend) the knees in order to allow the hips to flex. We’ll talk about this posture in the next section.
I have seen this referred to as the “psoas paradox.” Chronic tension in the iliopsoas can cause either hyperlordosis or hip flexion depending on the person’s full-body postural tendencies and the position of the body relative to gravity (standing vs. sitting vs. lying down).
Lastly, the iliopsoas laterally rotates the hips. This means that it rotates the legs so that the feet point outward like a ballet dancer. External hip rotation tends to occur along with the arching of the lumbar spine in action response posture.
So, in order to allow the iliopsoas to fully lengthen, we need to not only pandiculate the iliopsoas itself, but also the entire pattern of tension that’s keeping the pelvis stuck in a shortened state: the action response posture, in which the pelvis is tilted forward and the hips are rotated outward.
The tabs below list exercises that address the full-body pattern of tension that causes action response posture. After becoming comfortable with each individual exercise (by learning them in the Level One & Two Courses), you can start by practicing the short daily series, then rotate the additional exercises through your daily routine in a way that works for you.