The dynamics of posture

The notion of "Perfect Posture" conjure images of girls in finishing schools with books poised upon their heads. Along with that comes the squaring of the shoulders while slumped in a chair reading or using a computer. "Sit up straight!" we may have been told as children. The idea of a posture that works for all of us is a notion that I find unattainable and therefore sometimes harmful.

If we are continually chasing a perfection that is uncomfortable to our bodies, how is this beneficial. Posture is a dynamic state of equalibrium between gravity and bodies and the loads we place upon our bodies. Posture is a functional state, continually a hair's breadth away from falling down. At any one time, our tonic muscles are firing to pull us back upright, only to relax incrementally to allow the opposing muscle group to fire. This continuous tug-of-war is analagous to having a group of people arranged around a towering pole, each holding a rope connected to the top and each pulling gently as the pole sways away from them. When muscles become tight, the rope becomes taut on both sides of the pole and extra work is exerted on each taut rope.

Our posture is a function of our activities and our body structures (witness a person with an anatomical scoliosis, where vertebrae are not level and square but grew in a fashion that was unequal from right to left). This equation of form (the body we were born with) and function (what has happened to our bodies throughout our lifetime) is a constantly shifting state. We use what we have and we have what we use. Our bodies are remarkable durable and pliable in response to stressors, the forces that act upon it.

One constant for almost all of us is the force of gravity. The simple act of standing in resistance to the Earth's pull places a certain and constant force against our muscles and bones. During orbit, astronauts must replicate these forces to maintain their bone density, lest their bodies remove the calcium and other minerals which give their bones mass due to the lack of stress upon them.

We all choose a certain amount of forces to place upon our bodies and influence the stressors we are subject to. Our hobbies and our professions each have their own unique postural stressors. The increase of "carpal tunnel syndrome" and "thoracic outlet syndrome" are responses to the stresses placed by computers, mice, joysticks and telephones, among others.

Similarly, we can make choices about how we want our bodies to function and make inroads towards those changes. The cyclist who spends the winter on their trainer in a relatively relaxed period may find an adaptation period necessary when they return to stress of the riding in the wind and in a more aerodynamic position. After being subjected to a humerus (upper arm bone) fracture, an 83 year old client's goal in physical therapy was to be able to have sufficient range of motion at the shoulder to do her hair. Through stretching and strengthening exercises along with manual therapy, she was able to return to living by herself. She knew what she wanted her body to be able to do and the physical therapy offered her the means to accomplish this.

As we resist these stressors, they leave an indelible mark upon our bodies, in the form of scarring, increases or decreases in structural (skeletal, muscular, tendinous, fascial) mass, length and tone. We each meet these in a way that allows us to meet the functional goals that we need and/or want. How that happens for each body is unique and different and may not fit the image that our parents and teachers expected from us. The bottom line is that it works. It may be painful, it may create compensation patterns that are injurious to other structures but it works.

Rather than subjecting ourselves to the "perfect posture", we should give ourselves permission to function comfortably and efficiently, while meeting our goals. Next time someone tells you to sit up straight, think about how your body feels and what you want it to do for you.