Submitted by: Jeremy Nelson MPT

I recently collaborated with a patient on improving their mobility and function. They had a history of general aches and pains and the normal age related changes in the body that you would expect. The patient had seen a number of different therapists and trainers that were engaged to help him be able to walk better. What was provided was a number of separate exercises with the purpose of restoring flexibility and strength of the different extremities and his core. He did these and saw little change in his ability to perform on uneven surfaces.
I had an opportunity to review with the patient there previous programs and recognized the approaches as focusing on restoring and improving strength and flexibility. Not a bad approach, however there were a few critical tasks absent. By adding in a few changes to the previous program and combining many of the separate exercises into complex motions, the patients neuromuscular system was provided a new challenge and opportunity for consolidation of learning that would support the outcome the patient wanted.
As a result I found myself again pondering the relationships of functional movement and our body’s capacity to change postures, develop motion and change shapes depending on the circumstances. It is the complexity that exists in function and the simultaneous simplicity of form that gives rise to this complexity that fascinates me. It’s the gift that keeps on giving.
The fact of the matter is you can have extended knees and hips, strong and flexible but still not be able to walk with confidence over a variety of surfaces? Although important parts it is the unseen elements of human motion that are determinant in the success or failure of the brain to orchestrate movement. In this case it was the humble weight shift that is the key to the successful control of the body, maintaining balance over many types of surfaces. It happened to be the critical task that was missing in the approach to turn strength into function.
Our lives have a number of dimensions in them, and we interact with those dimensions through the activities that we participate in. It is this level of involvement that we as humans seek. And we seek to have a variety of involvement whether it be raising a family, performing a job, seeking entertainment, and participating in community or family events. It’s the unseen changing of positions of the COG to establish new bases of support and then repeating the shifting of position hundreds to thousands of times in day that we call function.
Each one of these activities includes different physical and mental demands. These demands are observable and measurable. Walking to an event can be observed and further analyzed into the gait cycle components. This analysis helps to more clearly understand what is happening in terms of the two key data points, COG and BOS. If fact, the brain acting like the conductor and composer of a musical score, directs the muscles, joints, bones to take on specific postures and positions at the correct time to support new postures and positions. The sequences are in support in the COG and BOS relationship, the fundamental relationship that provides the control for the force produced by the chemical reactions of nerves and muscles.
As the COG and BOS change position and shape, a new demand is imposed on the body and the neuromuscular system reacts by producing postures and movements to control the COG over the changing BOS. If the system is not flexible enough or strong enough or coordinated enough to produce the needed change in the COGBOS relationship, then compensatory patterns may by utilized. Although successful in the short term, these compensatory patterns often impose demands on tissues and joints that are not structured in a way to guide or absorb. As a result, tissues change, often with long term degeneration. Contrasted with a structure that guides the forces, the tissues would be enhanced and stimulated to grow to develop more capacity.
What makes the difference between a need for a compensatory movement or not is the capacity for the structure to complete the critical task necessary during that phase of the COG and BOS. When the structure of the body lacks the necessary flexibility or strength to control the dynamic relationship of COG and BOS, the brain will call upon available components to manipulate the COG and BOS relationship. As in any relationship, manipulation over time will lead to degradation of the relationship. In this case, component parts that are being asked to perform in a manner that the shape of the joint and arrangement of muscles are not structured to attenuate the forces at play will lead to break down of the bony and soft tissues over time. With an eye on the critical tasks, treatment and conditioning approaches can incorporate the essential elements in function, to support the client or patients capacity to be involved in life, as they desire.