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Tendonitis Symptoms Caused By Repetitive Strain Injury

Tendonitis symptoms are inflammation, burning sensation, pain and swelling at either a joint or at the point where the muscle inserts into the tendon.

There is overlap in the tendonitis and tendinosis symptoms and the two are often confused. A key difference is tendonitis has inflammation and tendinosis does not. The information on this page is strictly addressing tendonitis symptoms.

How Tight Muscles Cause Tendonitis Symptoms:


As an athlete, you are seriously prone to repetitive strain injuries because you cycle for hours, run long distances, swim, play ball or lift weights extensively. You continue doing the same movements over and over, causing the muscle fibers to shorten. The problem is, the muscles are still attached to the tendons and bones on either end of the muscle.

There is a phenomenon called “muscle memory” which explains how you improve at your sport by doing the same movement repetitively. Muscle memory also explains that when a muscle is held in a contracted position for an extended period of time it will actually shorten to the contracted length, which then puts a strain on the two ends of the muscle.

This is where tendonitis symptoms come in. The muscle fibers are shortened and pull on the insertion point either where the muscle merges with the tendon or where the tendon inserts into the bone.

How tight muscle fibers cause tendonitis symptoms, weaken your power and prevent joints from moving freely:


The biceps and triceps muscles make it easy to demonstrate.

When the biceps contract the elbow bends enabling the hand to touch the shoulder.

Consider what happens if the biceps muscle is shortened from muscle fiber knots after you’ve had your arm bent for hours – such as when you ride your bike for long distances.

The shortened muscle won’t allow your arm to straighten fully. When you force your arm to straighten it puts pressure on both the front of your shoulder and also on the inside of your elbow. This causes tendonitis symptoms in both areas.

When you look at the picture above, notice that the triceps must be fully lengthened in order to touch the shoulder. If there are muscle knots in the triceps you cannot touch your shoulder. You may be told to “strengthen your biceps” but the problem isn’t the biceps; it’s the tight triceps.

The tight muscles also cause the tendonitis symptoms of joint pain and stiffness. You also need to look at the opposite muscle – in this case, your triceps.

As the triceps contract, the biceps need to fully lengthen.

When you think of the synchronicity of the two muscles as one contracts the opposite stretches you have a better understanding as to how muscles cause tendonitis symptoms.

If your triceps are in spasm (contains muscle fiber knots), the biceps are unable contract fully which limits range of motion.

Both muscles need to be free of spasms that tie the fibers in knots and inhibit their ability to function properly.

Do NOT Stretch Until You Release Muscle Knots:


You are often advised to stretch tight muscles, but this is often the exact WRONG advice as you can tear the muscle fibers.

Here’s a good analogy:

Think about taking a 12″ length of rope and tying enough knots in it so it is now 11″ long – then try to stretch the rope back to 12″ without untying the knots. You can imagine how that makes the knots tighter and overstretch the fibers that are on either side of the muscle knot.

First you need to “untie” the knots in the muscle fibers and then you can safely stretch without injury.

The good news is that releasing the knots in the muscle fibers is easy.

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