Written by physiotherapist: Daniel Evans

What is a tendon

A tendon is the connective tissue in the body made up of a matrix of collagen fibres and water that attaches muscle to bone. They transfer the forces produced by muscles into the bone in order to produce movement. Tendons are also able to store and reuse energy produced by the muscles, much like a spring. The spring will absorb the load placed on it and then when it is taken off, it will rebound! 

What is tendinopathy

Previously, tendon pain was given the term ‘Tendinitis’. The suffix ‘-itis’ implies that the tendon is ‘inflamed’. However new research into tendon pain has shown that it is not necessarily an inflammatory process, but rather the breakdown of the matrix of the tendon, and the body’s subsequent ‘failed healing response’ that causes pain. If excessive loads are placed on a tendon repetitively, and the tendon is not given time to adapt, this will trigger the start of the tendinopathy process. The cells begin to break down and become disorganised and as much as the human body tries to heal the tendon, its attempts are usually in vain. This failed healing response is called a “Tendinopathy”.


Tendons are just as adaptable to load as muscle fibres are, meaning they both have the capacity to get stronger with increased loads, or weaker with reduced loads.

Two main causes of Tendinopathy are a sudden or long-term overload of the tendon, as well as compression of the tendon.

  • Sudden overload often comes from large and fast increases in load. For example, a 40-year-old male who has never really been a big runner decides that he wants to lose weight, so starts running daily. Within 2 weeks, he starts to develop Achilles tendon pain. Although his distances aren’t very long, it is more that he has not given his tendon any time to rest and adapt because he is running daily.
  • Compressive overload comes from tendons getting squashed or from repetitive rubbing. For example, a 30-year-old woman decides she wants to do her first triathlon, despite not having done much cycling in the past. She buys a new bike and starts cycling 3-4x/week and soon notices pain on the bony part of her buttock where she has been sitting on the firm bike seat. The hamstring tendon that attaches on this area is now getting squashed between the bone and the bike seat and this has resulted in a tendinopathy

Stages of Tendinopathy

The reactive stage is usually caused by sudden increases in load. The tendon cells will absorb more water content and get swollen. If the load is reduced and time is given for the tendon to adapt, it will return to normal. If excessive load continues, it will progress into the disrepair stage.

The disrepair stage means “failed healing”. The collagen fibres become disorganised and new blood vessels and nerves will grow in the tendon to try to promote healing. With appropriate management and load modification it is still possible to return this tendon to normal.

Chronically overloaded tendons that are unable to repair themselves will turn into a degenerative tendon. Small lesions will develop where the tendon cells and collagen have broken down. Although these lesions are irreparable, we often use the analogy of a donut – even though the donut has a hole in its centre, it doesn’t matter because the rest of the donut around the hole is still delicious. In this regard, it doesn’t matter so much about the small lesions if the rest of the tendon tissue is strong and healthy!


Treatment starts with an accurate diagnosis performed by a physiotherapist which places the injured person into the appropriate stage of the Tendinopathy process. Treatment itself will vary depending on this the phase.

If you do have tendon pain, it is important to come and see one of our experienced physiotherapists so that we can assess the injury and design a rehab program to suit your stage of injury. In the meantime, here are some top tips for tendinopathy rehabilitation.

  1. Tendons DONT like to stretch
  2. Tendons DONT like to be compressed
  3. Tendons DONT like SUDDEN CHANGE
  4. Tendons DONT like COMPLETE REST – activity modification is omportant
  5. Pain during exercise is ok, as long as it is not worse 24-72 hours laters
  6. Tendons LIKE heavy, slow loading and gradual progression to explosive activities.



Daniel Evans