Tag: gravity

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Balance

The stability or mobility question has been brought to the table many times. Which is more important ~ to be stable or to have mobility?

There are different perspectives to the answer depending on one’s field of study, the application, and the lens that you look through.

Here is my take: stability and mobility are in an interdependent relationship. One can’t effectively happen without the other.

Stability and mobility rely on each other to keep the structure safe. Stability is to software as mobility is to hardware. Stability requires motor control, the ability of the nervous system to respond appropriately as movement occurs. Mobility is the hardware, the organization of bones, joints, ligaments, tendons, muscles and fascial structures. The structure is responding to movement, messages of how movement is occurring, and how this information is being relayed up to the motor control center. A strategy is then derived as a response to the changing environment. The quality of movement being expressed is a product of integration of both stability and mobility.

Dynamic Stability is perhaps a better term to describe the product of stability and mobility. The question then shifts from “stability or mobility” to whether the body can appropriately respond to movement over a complete range of motion and a changing environment. For example, if you are hiking a steep loose trail, and the earth shifts under your feet, is the responsive mobility available for you to keep from losing footing and possibly spraining an ankle?

Dynamic Stability keeps the structure safe. The result of stability + mobility is neuromuscular integration that is available to respond appropriately to a complete range of motion. When life happens, and the environment shifts in an unforeseeable way, dynamic stability ensures an appropriate response is available.

In the movement known as the walking gait, the Lateral Kinetic Chain completes this dynamic platform. The body has just absorbed the kinetic energy through the deep longitudinal kinetic chain, the strike phase of the gait. That energy now needs to be grounded into a stable yet dynamic platform, the lateral kinetic chain, that will allow the body to generate the next movement, the power generation of the posterior spiral kinetic chain. The axis of the spine is integrating all three planes of motion while centralizing the energy from the previous shock absorption phase. As a result of dynamic stability, the body is prepared to generate propulsion, the forward motion of the walking gait.

The midline action of maintaining balance is another important action of the lateral kinetic chain. Complementary neuromuscular activations are working in cooperation to balance the relationship of movement, kinetic energy, gravity, and ground force reaction. These complementary actions provide the dynamic base so that the appendicular skeleton can generate energy.

Movement is a balancing act between environmental factors and the structure’s ability to respond appropriately. For example, when we look at the sculpture of rock stacking, we see the dance between the unique attributes of each rock. The size, shape, and center of gravity of each influences the balance point. Each rock complements the previous. The balance points create an axis, an axis of stability. Without this axis, the stack of stones would fall.

This demonstrates the third principal action of The 5 Primary Kinetic Chains ~ Axial Stability for Appendicular Mobility. When a dynamic base is in place, the appendicular skeleton can express its potential of generating stored elastic energy in movement.

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Shock Absorption

The second primary action of The 5 Primary Kinetic Chains is shock absorption. Shock absorption is the kinetic energy as it waves through the body. This concept has several contextual layers, let’s further explore shock absorption.

Kinetic energy refers to mass in motion. The earth we live on is a spinning ecosystem that comprises of many elements. Gravity is one of those elements (https://en.wikipedia.org/wiki/Gravity)

When we walk, run, or jump, our musculoskeletal system puts into motion the mass or weight of our structure. The product of the interaction between musculoskeletal activation, gravity, and ground engagement produces a wave of energy, a kinetic wave. Energy is a wave form, as it has a measurable amplitude and modulation. The amplitude is the height of the wave, or intensity, and modulation is the length of the wave, or duration.

When we are standing still, gravity is pressing our structure into the earth. In order to counter gravity, or to balance the force of gravity, we push into the earth creating a rebound. As the popular yoga saying explains, one must “root to rise, or stand tall like a mountain.” Without this action to counter gravity, we would collapse under its compressive force.

When we add momentum, our kinetic energy increases, and more energy is required to counter-act the compressive forces. Let’s explore this experientially. Take a few normal steps and notice how the impact of the strike phase of the gait is reverberating up your structure. Now increase the kinetic energy and transition from a walk to a trot. Notice how your body requires more of your structure to dissipate the energy.

Let’s increase the energy wave another notch. Try jumping up with both legs. See how much vertical height you can clear. Feel the leg drive from pushing into the earth and the absorption of kinetic energy as you reengage with the ground as you land. Now do the same thing, but drive and land with one leg only. Notice that that single leg absorption is asymmetrical. Take inventory of how this energy moves up the body, joint by joint. This is ground force reaction and is a key principal action in movement.

What happens when a joint or multiple joints are unable to participate in the distribution of kinetic energy throughout the body during the shock absorption phase of a movement? The structure must come up with a solution to dissipate the kinetic energy, this is called a compensation pattern. This is a maladaptive learned behavior that then is reinforced with each cycle of shock absorption.

Shock absorption is an essential element in structural assessment for integrated movement. The kinetic chain chart in the Deep Longitudinal anatomy poster gives great insight into how the energy of shock absorption waves through the body.