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What Causes Repetitive Stress Injuries?

Causes of Repetitive Stress Injuries – Understanding RSI Causes


The specific cause of the repetitive stress injury is dependent on the actual injury type. However, most repetitive stress injuries have similar contributing factors.


Trauma is one of those factors. Trauma means that we are causing discomfort to an anatomical feature. This either weakens the feature or otherwise causes it to reinforce itself.

Weakening can be represented by tears, breaks, inflammation, etc.

Some examples of weakened injuries are:

Reinforcement is the body's natural protection process. During exercise you actually breakdown and tear the muscles. The body then creates more muscle fibers than were destroyed to increase the strength of the muscles. Other anatomical features can do the same thing.

The body can reinforce an anatomical feature to strengthen it, like the muscle, or protect it, like a callus. It can also reinforce a joint to increase stability. This usually occurs by building up bone or tightening ligaments to reduce the range of motion.

Reinforcement can be helpful or harmful. When the body does it without your knowledge or direction it can lead to injury and body deformation.

Some examples of reinforcement injuries are:

  • Trigger Finger
  • Bunyan
  • Calluses
  • Blisters
  • Bone Spurs


Repetition is a common factor. Repetition of trauma from an activity. If the activity strains the body, even minutely, the build up of trauma over time can lead to a break down of that anatomical feature causing an injury.

The trauma level does not have to be constant. The harder the strain the more it will accelerate the build up. However even slight trauma, when done long enough, can cause a collapse.

Think about the Grand Canyon. A little stream ran across rock for a long time and cut a humongous gorge through stone.

Posture and Body Mechanics

Another factor is poor posture or bad body mechanics. The body is designed to work a certain way.

  • Joints have a range of motion.
  • Bones provide a frame work.
  • Nerves send the instructions and provide feedback.
  • Muscles contract to move the skeleton.
  • Bursas lubricate the joint.
  • Tendons and ligaments hold it all together.
  • Other parts do other things.

Everything has a function and moves a certain way. Performing an action with a bad posture or body mechanics forces the body to move in a more difficult way.

Poor posture and bad body mechanics can also cause poor circulation. Circulation is vital to a healthy body. It delivers the fuel. Without fuel the body is forced to function less efficiently and that places more strain on it.

Using the wrong muscles is another example of bad body mechanics. Some actions do not require a great deal of strength at the final body link to perform an action. You can generate the momentum needed in other body parts and let the rest whip around to final position.

Think about how you throw a baseball. Momentum is started in the hips and transferred to the arm. The arm then generates the bulk of the strength needed. The hand is used for fine control as it whips into position.

You can generate a lot more speed this way, but since muscles are meant to control motion it can overextend those joints and strain them. Sprains and pulls are common. Major league pictures have even broken their arms simply by throwing the ball.

Body in Motion

A lot of products and setups are designed to support you in a good posture. This is beneficial but it misses an important point. The body is meant to move.

Muscles are designed to move. They are not designed to stay in the same position for hours on end. Static strain is very fatiguing.

Movement also helps circulation.

Overall Health

Your health is a contributing factor to developing a repetitive stress injury. If you are unhealthy or overweight you are already straining your body. Your circulation is less than it should be and your body has to carry more weight. That makes you more susceptible to repetitive or acute trauma.

Mental Stress

Not to be confused with the physical stress in repetitive stress injury, mental stress can contribute to the injury. In some respects stress is stress no matter what causes it. More to the point mental stress can materialize in physical symptoms.

It will usually show up in the weakest part of your body. If you are already developing a repetitive stress injury there is a good chance a high mental stress level will exacerbate it.

The Problem Task

Most repetitive stress injuries can be contributed to a specific task. Yet once the injury has occurred other actions that would not have caused a problem on their own now further traumatize the injured area due to its weakened status.

Discovering the problem tasks can be difficult but there are ways you can do it. By understanding what your repetitive stress injury is, tracking your pain on a visual pain scale and analyzing your tasks you should be able to find the culprit and correct the situation.

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