Tendon Pain: Tendinitis, Tendinosis or Tendinopathy and Why Loading Matters

Achilles pain. Tennis elbow. Jumper’s knee. Rotator cuff pain.

If you’ve experienced tendon pain, you may have heard several different terms used to describe it: tendinitis, tendinosis or tendinopathy.

They sound similar, but they don’t quite mean the same thing. Understanding the difference can change the way we think about treatment.

First: what is a tendon?

A tendon is the strong connective tissue that attaches a muscle to a bone.

Every time you run, jump, lift, throw or even walk, your tendons help transfer force from your muscles into movement.

Tendons are designed to tolerate load.

Problems can arise when the load being placed on a tendon exceeds what that tendon is currently able to tolerate.

That might happen after suddenly increasing your running distance, playing more padel than usual, returning to the gym after a break, or simply doing something your body hasn’t been adequately prepared for.

Tendinitis vs Tendinosis vs Tendinopathy

Tendinitis

The ending “itis” means inflammation.

Historically, persistent tendon pain was commonly labelled “tendinitis”, with the assumption that inflammation was the primary problem.

We now know the biology of persistent tendon pain is considerably more complicated than simply having an inflamed tendon. That doesn’t mean inflammation can never be involved, particularly in more acute presentations, but calling every painful tendon “tendinitis” can be misleading.

Tendinosis

You may also have heard the term tendinosis.

This has traditionally been used to describe degenerative or structural changes within a tendon rather than inflammation.

However, tendon structure and tendon pain do not always match neatly. A tendon can look abnormal on a scan without causing symptoms, and structural changes don’t necessarily tell us how much pain someone should experience.

For this reason, international tendon experts have questioned the usefulness of “tendinosis” as a clinical label.

Tendinopathy

This is now generally the preferred term.

International consensus defines tendinopathy as persistent tendon pain and loss of function related to mechanical loading.

In other words:

The tendon hurts when we ask it to do its job.

This definition is useful because it focuses less on trying to decide whether a tendon is “inflamed” or “degenerated” and more on the things that actually matter to the patient.

Pain. Function. And the ability of the tendon to tolerate load.

So should I rest my tendon?

Usually, complete rest isn’t the long term solution.Reducing an aggravating activity temporarily can be sensible. If running 40 km per week is continually irritating your Achilles, for example, modifying that load may allow symptoms to settle.

But there is an important difference between managing load and simply avoiding load altogether.

Tendons need mechanical stimulus.

And this is where rehabilitation becomes particularly important.

The treatment? LOAD.

One of the most consistent themes in modern tendinopathy rehabilitation is progressive exercise and loading.

Rather than trying only to “settle” the tendon, rehabilitation aims to gradually improve its ability, as well as the ability of the surrounding muscles, to tolerate the demands you want to place upon it.

Depending on the tendon, your symptoms and your stage of rehabilitation, this might progress from:

Isometrics → controlled resistance training → heavier strengthening → faster loading → jumping, running and sport specific loading.

Not everyone needs exactly this sequence, and there isn’t one magical exercise programme that works for every tendon.

What matters is finding an appropriate starting point and progressively increasing the demand.

Research supports resistance exercise as an important treatment for tendinopathy, and evidence suggests that appropriately loaded resistance programmes can produce better outcomes than very low load exercise alone.

Pain doesn’t always mean damage

This is another important concept.

A painful tendon does not automatically mean you are continuing to “tear” or damage it every time you use it.

Some discomfort during rehabilitation may be acceptable depending on the individual and the tendon being treated.

The important question is often not simply:

“Did that exercise hurt?”

Instead, we might ask:

“How did the tendon respond to that amount of load over the next 24 to 48 hours?”

That response can help your physiotherapist decide whether your programme should be progressed, maintained or temporarily reduced.

The goal isn’t simply to make the pain disappear

If you only reduce pain without rebuilding capacity, the original problem may still be waiting for you when you return to running, football, padel or the gym.

Good tendon rehabilitation therefore aims to achieve something bigger:

Reduce symptoms → restore strength → increase tendon and muscle capacity → rebuild the demands of your activity → return to what you enjoy doing.

So if you’ve been told to simply rest a painful tendon indefinitely, it may be worth looking at the problem differently.

Your tendon may not just need less load.

It may need the right load, at the right time, progressed in the right way.

Why not contact us today, to find out how physiotherapy can help you. Or you can easily book an appointment online.