What is Optimal Movement?
What makes movement good—can we define it or can we list principles of optimal movement? Notice that these are subjective/qualitative terms. We are not asked to transform society (as per 2013 APTA vision) by improving goniometric measurements or manual muscle testing scores, but by improving quality of movement. I will address two of the four principles in this blog—postural alignment and minimization of unnecessary effort.
While quantitative movement characteristics (how many, how much, how far and how long) are an aspect of well-organized movement, and are easier to observe and measure, they do not by themselves constitute optimal movement. We could define optimal or most desirable with terms like smooth, fluid, satisfying, comfortable, efficient, easy, gratifying or painless, but these are sensations unique to the experiencer and are hard or impossible for observers to assess.
Is there a middle ground between unobservable subjective experience and objective but incomplete measurable criteria? Yes, if we have an understanding of how integrated bodies are coordinated and can move beyond a simplistic anatomical framework for understanding human movement.
The Fabulous Four
As a starter, we can propose four basic principles of optimal movement. We can observe violations of these principles and medically articulate why sub-optimal movement creates or perpetuates musculoskeletal misery. We should then have ways of getting our patients to recognize the error of their ways, as well as suggesting options that our patients can agree are better in terms of their presenting musculoskeletal complaint. Keeping open the possibility of further refinement or additions, what are these four proposed principles?
- Postural Alignment or Fascio-Skeletal Weight Bearing
- Minimization of Unnecessary Effort or Conservation of Energy
- Appropriate Distribution of Movement or Addressing Hypermobility/Hypomobility Pairs
- Proportional Use of Synergists or Working Big Muscles Harder & Small Muscles Less
We will deal with the first two in this blog and tackle the rest in the next installment. Bones aren’t square blocks and don’t have flat surfaces, so stacking them without some ligamentous and muscular support is impossible. The concept of tensigrity as proposed by B. Fuller has merit here. Fascio-skeletal weight-bearing (or alignment) means arranging bones to create an inner sensation of solidity or easy support. Alternatives to fascio-skeletal weight-bearing are ligamentous or muscular weight-bearing.
Ligamentous & Muscular Weight Bearing
Examples of ligamentous weight-bearing are—foot pronation, knee hyper-extension or valgus, hanging on hip Y-ligaments, slamming onto trochanteric bursa while one-leg flop standing, and sagging against spinal ligaments in slouch sitting. Possible consequences of habitual and long-standing ligamentous weight-bearing are ligamentous and capsular over-stretching, postural muscle weakness and joint hypermobility.
Examples of muscular weight-bearing are: standing with weight forward on toes (calf hypertonus and hammer toes), standing or sitting with lumbar hyper-extension (extensor hypertonus and facet compression) and forward head posture (cervical hypertonus and lower cervical shearing). Possible consequences are muscular over-use and myofascial syndromes and, through the mechanism of reciprocal inhibition, chronic antagonist muscle imbalances.
Conservation of Energy
Minimization of effort means more than just conservation of energy—sitting slumped or hanging on the trochanteric structures conserves energy, but violates the principle of bearing weight skeletally. Minimizing effort means not doing more/working harder than is necessary for the task at hand, whether this is blissing out in your recliner or engaging in some heart-pounding, sweat-popping, vein-bulging athletic endeavor.
It means coordination of antagonists—smooth, efficient and appropriate reciprocal inhibition so you aren’t working against yourself, not driving with your brakes on. This can be difficult to see, but can be assessed manually and positively influenced relatively easily. Minimization of effort also encompasses the vast subject of physical manifestation of emotional stress—holding your breath, clenching your jaw, pulling your shoulders up/in, furrowing your brow, etc.
Reducing superfluous effort also pertains to cultural idiosyncrasies—sucking in your gut, sitting ‘lady-like’ with your knees/feet together, gentlemen puffing out your chest and pulling your shoulders back, etc.. These can be easier to see but harder to work with—they are often ingrained into a persons’ identity. The next two principles, distribution of movement and proportional synergists, are addressed next and provide an introduction to movement integration styles or choices.