Achilles Tendinitis

By 15 January 2020Injury Rehab, Latest

Achilles tendinitis, forming “the big four” of running injuries along with runner’s knee, shin splints and plantar fasciitis, is an injury many runners will have at least heard of. As the name suggests, Achilles tendinitis affects the Achilles tendon, which attaches the calf muscle to the back of the heel. Tendinitis? Tendinosis? Tendinopathy? You may encounter all three of these terms, which can be confusing. Before discussing Achilles tendinitis any further, it is probably useful to define and explain the differences between them.

  • Tendinitis is the inflammation of a tendon, occurring after an acute stress (e.g. an accident or a particularly intense training session) which causes small tears in the tendon fibres.
  • Tendinosis is the degeneration of a tendon, which happens when a tendon is chronically overused and strained, developing small tears that don’t have time to heal, and so the entire structure accumulates damage.
  • Tendinopathy is a general term used to designate a tendon injury. Many conditions that used to be called tendinitis are actually tendinosis, and although it was once thought that tendinitis led to tendinosis, current thinking has this the other way around. Therapists often use the term tendinopathy when there is insufficient evidence that the symptoms are due to one or other distinct condition. 


Tendinitis normally implies strain, which implies overuse. Remember that, in training terms, overuse can mean a sudden increase in load (distance, duration, intensity), or a decrease in recovery (quality or quantity), or both. As always, worn-out or inappropriate footwear can also contribute to excessive loading of the calves and Achilles tendon. 

Usually, Achilles tendinitis starts as tight calf muscles, which transmit strain into the tendon, which becomes inflamed and then brittle. If left unchecked, Achilles tendinitis can lead to the tendon tearing, which is a serious injury that can require surgery. 

Tendons in general, and the Achilles in particular, are more susceptible to injury in cold weather, so gradual but thorough warm-ups are important. Previous injury can also result in a thickening of the tendon which will make it more prone to re-injury. 

Achilles tendinitis will tend to affect older athletes, and shorter-distance runners over longer-distance runners. 




Pain will be felt in the Achilles tendon itself, anywhere from the lower leg to the insertion (where the tendon attaches to the bone) at the back of the heel. There may be clear signs of inflammation: heat, redness, and/or swelling. 

Pain is often worse in the morning. 

Achilles tendinitis should be fairly easy for a professional to identify, with the help of a case history and some palpation (touching the area to identify exactly where the pain is, and to feel for inflammation). Scans are usually not needed, but can help identify if there is a tear, or rule out other conditions that could give similar symptoms if your therapist suspects there could be any. 

If the tendinitis becomes tendinosis, the tendon may develop a painful lump. This lump normally remains after the injury has healed, but will no longer elicit pain. 


Like all inflammatory conditions, it is important to rest your Achilles tendon and calves until the acute inflammation subsides – this means avoiding or limiting any activities that require you to push off the ball of your foot, including walking. 

Ice and over-the-counter medication can help manage the inflammation, elevation and compression (of the calf) can help encourage circulation and the body’s natural healing processes. Shoes with a slightly raised heel (we’re not talking high heels here, but rather trainers with a more pronounced drop) can help reduce strain on the Achilles while it is healing. Stretching the calves should be avoided during this phase as it may re-inflame the Achilles, but massage can help decrease tension in the calves and increase circulation around the Achilles tendon, which normally does not benefit from ample blood flow. 

Once the inflammation and pain have subsided, you can gradually return to activity with the inclusion of a proper rehabilitation programme. Rehab is likely to involve stretching, and eccentric strengthening (e.g. going up onto your toes with both legs on the ground, and lowering your heel back down on one leg). It is important that this rehab programme be overseen by a professional, who can judge how much load is appropriate and at what point to progress your exercises. 

Depending on how severely the tendon was affected, and how it has healed, deep friction (an aggressive, deep massage technique) may be recommended by your therapist in order to break up brittle scar tissue. This will be painful and may cause some inflammation, which can be managed as above, but ultimately should result in fewer issues in the longer term. 

As with all overuse injuries, developing Achilles tendinitis is a signal to review your training regime and/or equipment. Have you increased your running mileage too quickly? Are your shoes worn down? Have you accumulated too many sessions without adequate rest, or have you failed to stretch or include some cross-training? Allowing your body to heal fully and addressing all relevant issues – ideally with the help of an experienced professional – will enable you to get much more from your training going forward!

If you think you may be suffering form an Achilles injury, do not hesitate to get in touch with us at Ealing Fitness clinic to get it diagnosed and treated so that you can go back to your sport as quickly as possible!

Contact us for a free consultation

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