Achilles tendinopathy is one of the most common overuse injuries in runners and in anyone who jumps, plays court sport or stands for long periods. It typically sneaks up as a stiff, sore tendon at the back of the ankle that’s worst for the first few steps in the morning and when you start to run, then eases once you warm up, before flaring again afterwards.
Understanding Achilles tendinopathy
The Achilles is the thickest and strongest tendon in the body, transmitting the force of the calf muscles to the heel. When the load on it increases faster than it can adapt, such as a new training block, more hills, a change in shoes or a sudden return to sport, the tendon becomes painful and loses some of its capacity. As with other tendon problems, it’s mostly an issue of load tolerance rather than inflammation, which is why simply resting rarely fixes it. See our tendon pain page for the underlying principles.
There are two main presentations:
- Midportion Achilles tendinopathy: pain in the body of the tendon, about two to six centimetres above the heel
- Insertional Achilles tendinopathy: pain at the back of the heel where the tendon attaches to the bone
Symptoms we commonly see
- Pain and stiffness in the Achilles first thing in the morning or after sitting
- Pain at the start of a run or jump that eases as you warm up, then can return afterwards
- Tenderness, and sometimes thickening, in the tendon
- Pain with hills, speed work, jumping or stairs
- Reduced calf strength and endurance on the sore side
Our evidence-based approach
Clinical practice guidelines support progressive exercise-based loading as the foundation of Achilles care. Several loading programs work, and a randomised trial found heavy slow resistance training was as effective as eccentric training, with people tending to stick with it better. Our approach includes:
- Assessment of the tendon, calf strength and endurance, ankle movement, footwear and training load, to identify what pushed the tendon past its capacity
- Load management, adjusting running volume, hills and jumping so symptoms settle without you stopping everything
- Isometric holds early on if the tendon is irritable, which can also ease pain for some people
- Progressive heavy loading of the calf, through slow, heavy single-leg raises and related exercises
- Energy-storage work such as skipping, hopping and running drills, introduced as the tendon tolerates it
- VALD strength testing of calf strength, so we can compare sides and track your numbers across rehab
- A graded return to running and sport, with strength and capacity criteria rather than a date
What to expect: recovery timeline
- Early or mild cases: often settle over several weeks once load is managed
- Established Achilles tendinopathy: typically needs three to six months of consistent, progressive loading for lasting change
- Long-standing cases: can take longer, particularly insertional problems, and benefit from reviewing everything contributing to the overload
When to seek help urgently
Seek prompt assessment for a sudden snap or bang at the back of the ankle with difficulty pushing off, a calf that is swollen, warm and red, or heel pain with fever or redness. If you’ve recently taken fluoroquinolone antibiotics or corticosteroids and develop tendon pain, tell your doctor promptly.
References
- Chimenti RL, Neville C, Houck J, Cuddeford T, Carreira D, Martin RL. Achilles pain, stiffness, and muscle power deficits: midportion Achilles tendinopathy revision 2024. J Orthop Sports Phys Ther. 2024;54(12):CPG1-CPG32.
- Silbernagel KG, Hanlon S, Sprague A. Current clinical concepts: conservative management of Achilles tendinopathy. J Athl Train. 2020;55(5):438-447.
- Beyer R, et al. Heavy slow resistance versus eccentric training as treatment for Achilles tendinopathy: a randomized controlled trial. Am J Sports Med. 2015;43(7):1704-1711.
- Millar NL, Silbernagel KG, Thorborg K, et al. Tendinopathy. Nat Rev Dis Primers. 2021;7:1.