The Receptive Injury Cycle

The Repetitive Injury Cycle

Injuries suck. They side- line us from life in general. The reasons we get injured varies. Most acute injury cause is obvious. Stepping on a land mine, getting steam rolled by a 250 lb. linebacker, forgetting your wife's birthday, (this actually can be fatal and not recommended!)

The most common cause of injury though is the Repetitive Injury Cycle. This is what most of us are susceptible to every day.

Any movement excessively done can potentially cause scar tissue to develop in the muscular system. This can lead to entrapped nerves, altered bio-mechanics, tendinitis, carpal tunnel, shoulder pain, sciatica, hair loss...(Okay, maybe not hair loss but a lot of other stuff.)

One of the great contributions Dr. Michael Lehey (the developer of ART, Active Release Technique), gave us was the Law of Repetitive Injury.

It's this: I = N * F


A * R

I = Insult to tissues

N = Number of repetitions

F = Force

A = Amplitude

R = Rest

Hey, the guy was an Air Force test pilot with a degree in Aeronautical Engineering from the Air Force Academy before he became a Chiropractor. Real brainy like. We both graduated from Los Angeles College of Chiropractic,although he probably had a slightly better GPA than me.

So, an example of how this math works is to compare the factors of working on a computer with, say, an Olympic cyclist.

The N, (number of repetitions) will be high in both groups.

F, (force),will be astronomical in the cyclist group but low on the computer.

A, (amplitude), will be high with the cyclist and very low on the computer.

R, (rest), will be low in both groups.

Remember basic math. Anything in the numerator that goes up and anything in the denominator that goes down, increases the product, I,(Insult to tissue.)

So, if the cyclist was going to have issues we would contribute this to the increase in F, force. (The factor in the numerator).

Where the folks on the computer would have issues as a result of the A, amplitude going down.

What is amplitude?

The maximum extent of a vibration or oscillation, measured from the position of equilibrium.

Think of the difference between an old fashion type writer and typing on a modern key board. That difference is amplitude.

It's interesting that almost no one got carpal tunnel on the dinosaur type writers where amplitude would be higher.

So another example of how when we make things easier we often create more problems.

What we can also see is what factors in that equation you can change to break this repetitive cycle.

In this case it would be R, rest.

I'm convinced that many acute injuries are actually a result of the distortions in bio mechanics that result in the build up of adhesion's, (scar tissue), from the repetitive injury cycle.

Take a piece of scotch tape and rub the smooth side across your skin. This is how muscles should glide over one another. Muscles that have scar tissue is more like the sticky side of the tape moving over each other.

After a while this creates enough change that the muscle has less tolerance to stress and is more prone to injury.


Another major factor in injury is lack of hydration. So much of our body is water. Dehydrated muscle cells are extremely susceptible to damage.

You should be drinking a minimum of 80 - 85 ounces a day. More if it's hot and your training hard.

Protein intake is a factor. Especially if your training or have a physical job. Most of us don't get enough protein. Muscles need a steady supply of amino acids that are essential for optimal function.

1/2 to 1 gram of protein per pound of desired body weight.

Essential fats greatly contribute to injuries if your not getting enough. They help control inflammation. You should be getting about 3 grams per day. The best source is pharmaceutical grade fish oil.

The key to avoiding the damage from Repetitive Injury is to break the cycle. That usually requires modulating R = rest.

Other factors can be influenced but are subjective on a case by case basis.

As always, if you or some one you know is injured or dealing with chronic pain the best advice I can give is get in here and let me fix it.

Till next time. Watching your back, Dr. Steve