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.