Thursday, March 25, 2010

What's The Way To Sway?


How is your neuromuscular system?

The living human body is always swaying (oscillating). The amount (amplitude) of sway will vary depending on the activity of the human body, such as standing, sitting, climbing stairs, walking, cycling, lying in bed, etc., Sway can be very minimal and unseen/detected by the naked eye (such as that of a gymnast or martial artist with fine muscular control), or it can be more pronounced, having a larger amplitude and easily be seen/detected by the naked eye (such as when standing and under the influence of alcohol).

As mentioned above, the living human body is always swaying, regardless of the activity. However, the topic of sway (and posture and balance) is here is not limited to the activity of standing still in an upright position, rather cycling motions.

Many don't understand the unseen! They claim, because they can't seen it, that it's static?
Our CAD, and science measures the unseen! Yet we can show you with software models that show you forces.

When standing, we sway because we do not want to fall. In other words, swaying is the defense mechanism we unconsciously use preventing us from falling. Here is a simplified explanation on what this means and how this works:

Since we are a living substance, we oscillate, and since we oscillate, we therefore lean in a specific direction. However, if we continue to lean we will eventually fall over. So as not to lean completely over and fall to the ground, we unconsciously contract muscles to create motion and movement, thus bringing the body back into an upright position by leaning in the opposite direction (we therefore recuperate from falling).

However, we “unconsciously overdo” the recovery movement because we want to “make sure” that we do not fall. Due to this over-defense response mechanism, we not only bring the body back up, we also create a new leaning in the other direction. Since we start leaning again, the unconscious defense recovery mechanism is triggered and called once more. Now think about a flexing bike being under you!

This cycle keeps repeating itself as follows:

The body leans
We recuperate from leaning
We over-recuperate to ensure we do not fall
We create new leaning in other direction

To recuperate from the leaning and prevent falling, we need to first "detect” that we are leaning, then “react" to recover the leaning and “act” to recuperate the leaning (and prevent falling).

Now comes an issue while on the bike, we are not in a normal bipedal/upright standing position!
All things change!

Detection (that we are leaning and thus falling) is achieved via our eyes, the 3 fluid canals of the inner ears, the mandible (jaw)/occlusion, and the bottom (plantar surface) of the feet. They are the “receptors” (proprioreceptors) that unconsciously inform us we are leaning.

Reaction comes when these receptors unconsciously trigger the neuromuscular system to “act” in order to “recover” (bring the body back up so as not to fall). Action (recovering from the leaning and thus falling) is achieved via our neuromuscular system. This is the “actor” unconsciously recovering the body from leaning and falling.

Detection and triggering of the reaction phases are in the care of our eyes, the 3 fluid canals of the inner ears, the mandible (jaw)/occlusion, and the bottom (plantar surface) of the feet (the receptors). Reaction and recovery phases are in the care of our neuromuscular system.

Consequently, sway is affected and/or influenced by our physical, physiological, neurological and/or psychological conditions, disorders and/or pathologies (bike fit) that act on (affect, influence and perturb) the proprioreceptors and the neuromuscular system.

Sway while standing can be and has been characterization via qualitative assessments and/or quantitative measures. This is because the COF (Center of Force) is a representation and a measure on body movement (swaying - leaning/falling and recuperating from the leaning/falling). An example of qualitative assessment is when the body is swaying front-to-back (anterior-posterior) and right-to-left (medial-lateral) and the swaying is in a very large circle. This is a qualitative method of measurement, not a quantitative measure.

An example of quantitative measure is when the COF (Center of Force) travels (moves/sways) in an area of 25 cm2, and the COF travels front-to-back (anterior-posterior) and side-to-side or right-left (medial-lateral).

No two upper bodies are the same! That affects the (Center of Force) and how your body moves with the bike. We now have the science to show you the unseen forces on hands, feet, sit bones while you pedal.

WN can show you the way to sway!

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