You've felt it on your first steps out of bed: a stiffness, sometimes a sharp ache, right at the back of the heel or a few centimetres above it. Maybe it eases after a warm-up, only to return the next morning. If you've tried rest, stretching or generic calf exercises without lasting improvement, it may be that the approach wasn't matched to your type of Achilles tendinopathy, and that distinction matters more than most people realise.
What Is Achilles Tendinopathy?
Achilles tendinopathy is a load-related condition involving pain, impaired function and changes within the tendon. Symptoms often develop when the demands placed on the tendon exceed its current capacity to tolerate and adapt to load. It is not simply inflammation, which is one reason anti-inflammatory strategies on their own rarely resolve it. It is also not a straightforward case of "damage equals pain". The amount of pain you feel does not map directly onto the structural state of the tendon, which is why two people with similar-looking tendons on a scan can have very different symptoms. Rest may be useful for temporarily reducing an aggravating load, but it does not rebuild tendon capacity on its own. Long-term rehabilitation usually requires progressive loading, adjusted to the individual's symptoms, function and goals.
Common Symptoms
Typical features of Achilles tendinopathy include:
- pain and stiffness at the back of the heel or lower calf, often worst first thing in the morning or after sitting
- pain at the start of activity that may ease as you warm up, then return afterwards or the next day
- tenderness when the tendon is squeezed or pressed
- pain or reduced tolerance with hopping, running, stairs or single-leg heel raises
- reduced calf strength or endurance on the affected side
Who Gets Achilles Tendinopathy?
Achilles tendinopathy is common in running and in other sports involving repeated running and jumping, but it can also affect people who are less active. Symptoms may develop when training load changes, recovery, previous injury, physical capacity and other individual factors combine to exceed the tendon's current tolerance. That might be a runner who has added volume, speed work or hills, someone returning to sport after time off, or someone whose day-to-day demands have changed. Calf strength and endurance are important components of rehabilitation, but weakness alone does not explain why someone develops Achilles tendinopathy.
Midportion vs Insertional: A Critical Distinction
Not all Achilles tendinopathy is the same, and the location of your pain shapes the approach to rehabilitation. Midportion tendinopathy affects the main body of the tendon, typically 2 to 6 cm above its attachment to the heel bone. This is the more common presentation. Progressive calf loading is appropriate here, which may include heel raises, heel drops and heavy slow resistance training depending on the individual's symptoms and capacity. A randomised controlled trial comparing heavy slow resistance with eccentric (heel drop) training in chronic midportion tendinopathy found similarly positive outcomes with both. Insertional tendinopathy affects the tendon right at its attachment to the calcaneus (heel bone). Here the tendon is sensitive not only to tension but also to compression, which occurs as the tendon wraps against the heel bone when the ankle moves into dorsiflexion (the foot bending up towards the shin). In a 2025 randomised clinical trial involving sport-active adults with chronic insertional Achilles tendinopathy, a rehabilitation programme designed to reduce tendon compression produced better clinical outcomes than a higher-compression programme at 12 and 24 weeks. The programme included limiting ankle dorsiflexion, avoiding calf stretching and using heel lifts. For an irritable insertional tendon, repeatedly loading the tendon into deep dorsiflexion may aggravate symptoms. This is why exercise selection and range of motion should be individualised rather than automatically prescribing heel drops from a step.
Do You Need an Ultrasound or MRI?
Achilles tendinopathy is usually diagnosed clinically, based on the location and behaviour of symptoms, examination findings and functional limitations. Imaging is not routinely required to diagnose uncomplicated cases. Ultrasound or MRI may be useful when the diagnosis is uncertain, symptoms are not following the expected course, a partial tear or other pathology is suspected, or imaging would change management. Importantly, tendon thickening and other structural changes can also be present in people without pain, so imaging findings need to be interpreted alongside the clinical picture. Not all pain at the back of the heel is Achilles tendinopathy. Bursitis, bony changes at the back of the heel, nerve irritation and problems at the back of the ankle joint can all produce similar symptoms, and assessment is about telling these apart.
When Achilles Pain Needs Further Assessment
Seek prompt medical assessment if you experience:
- a sudden "pop" or snapping sensation at the back of the ankle
- immediate loss of push-off strength
- difficulty walking normally after an acute injury
- significant swelling or bruising
- rapidly worsening symptoms
- symptoms that do not behave like typical Achilles tendinopathy
A sudden onset of pain with a feeling of being kicked in the back of the heel can indicate an Achilles tendon rupture, which needs urgent assessment rather than a tendinopathy programme.
Pain-Guided Loading: What It Means in Practice
Most people arrive believing that any pain during exercise means stop. In tendinopathy, it is more nuanced than that. Pain during exercise does not automatically mean that you are damaging the tendon. Some discomfort can be acceptable during rehabilitation, provided the overall response remains manageable. Rather than relying on a fixed pain threshold, monitor how symptoms respond during the session and over the following 24 hours. A clear and sustained increase in pain or morning stiffness may indicate that the recent training load needs adjusting. This does not mean you have to stop running completely. In many cases, running and other tendon-loading activities can be modified and progressively reintroduced alongside strengthening. In a randomised controlled trial, people with Achilles tendinopathy who continued running and jumping using a pain-monitoring model alongside rehabilitation did no worse than those who initially rested from those activities. Complete rest is not usually necessary. Instead, aggravating activities can often be modified while progressive loading is maintained. Progressive loading provides the stimulus the tendon and calf complex need to rebuild strength and load tolerance.
How Achilles Rehabilitation Progresses
Rehabilitation is usually progressed according to symptoms, strength, function and the demands the tendon ultimately needs to tolerate. Rather than following a rigid four-stage protocol, the emphasis is on gradually increasing the type, magnitude and speed of loading. The goal isn't to find the one "correct" Achilles exercise. A 2023 systematic review of randomised trials in midportion Achilles tendinopathy did not identify one loading protocol as clearly superior to another. What matters more is progressively exposing the tendon to the loads it needs to tolerate. Not every patient needs every component below, and they are not always introduced in a fixed order.
Common components of rehabilitation
Isometric loading. Isometric loading can be useful when dynamic exercise is poorly tolerated, particularly as an early way of introducing or maintaining calf loading. Isotonic strengthening (including heavy slow resistance). Progressive isotonic strengthening is a central component of rehabilitation and should be progressed as strength and symptom tolerance improve. This includes calf raises in standing and seated positions, with load added over time. For insertional tendinopathy, range of motion is usually adjusted to limit deep dorsiflexion. Energy storage and release. Running and sport place high demands on the tendon's ability to rapidly absorb and release force. Rehabilitation therefore needs to progress beyond slow strengthening towards faster, energy-storage activities, such as skipping, hopping and bounding, before a full return to running or sport. Sport-specific loading. Running progression, change of direction and the demands of your specific sport, reintroduced gradually and guided by how the tendon responds.
Calf Capacity Is More Than Strength
Calf capacity is more than maximum strength. Depending on the person's goals, we may also need to consider endurance, repeated single-leg loading, rate of force development and the ability to tolerate faster stretch-shortening activities. Running places substantial demands on the Achilles tendon. A systematic review estimated Achilles tendon loads of approximately 4.15 to 7.71 times body weight during running, although these are mechanical estimates from healthy populations and should not be treated as direct tendon loads in individual patients. The practical point is that a calf that feels fine during slow heel raises may still not be ready for repeated, fast loading over the length of a run.
How IP Physio Can Help
We begin by establishing where your tendon is symptomatic, ruling out other causes of heel and ankle pain, and identifying what type of load is aggravating it, because the distinction between midportion and insertional tendinopathy changes the programme. We avoid defaulting to heel drops off a step for an irritable insertional tendon, and we avoid prolonged complete rest for either type. From there, we use objective calf strength and capacity testing to quantify where you currently sit, and build a progressive loading programme that adapts to how your tendon responds. If imaging is likely to change your management, we will discuss whether it is appropriate. We monitor how your tendon behaves between sessions, adjust accordingly, and make sure the programme connects all the way through to your return to running or sport, not just to a point where you feel better at rest. If you've been dealing with persistent Achilles pain that hasn't responded to standard advice, we'd like to take a more systematic look at why, and what to do about it. Get in touch with us today.
Still have questions?
Read quick, direct answers to the questions people most commonly ask about Achilles tendinopathy, imaging, running and rehabilitation.
Achilles Tendinopathy: Frequently Asked QuestionsReferences
- Chimenti RL, Neville C, Houck J, et al. Achilles pain, stiffness, and muscle power deficits: midportion Achilles tendinopathy revision 2024. J Orthop Sports Phys Ther. 2024;54(12):CPG1-CPG44. doi:10.2519/jospt.2024.0302.
- Cook JL, Purdam CR. Is compressive load a factor in the development of tendinopathy? Br J Sports Med. 2012;46(3):163-168. doi:10.1136/bjsports-2011-090414.
- Pringels L, Capelleman R, Van den Abeele A, et al. Effectiveness of reducing tendon compression in the rehabilitation of insertional Achilles tendinopathy: a randomised clinical trial. Br J Sports Med. 2025;59(9):640-650. doi:10.1136/bjsports-2024-109138.
- Beyer R, Kongsgaard M, Hougs Kjær B, 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. doi:10.1177/0363546515584760.
- Maetz R, Dubé MO, Tougas A, Prudhomme F, Dubois B, Roy JS. Systematic review and meta-analyses of randomized controlled trials comparing exercise loading protocols with passive treatment modalities or other loading protocols for the management of midportion Achilles tendinopathy. Orthop J Sports Med. 2023;11(5):23259671231171178. doi:10.1177/23259671231171178.
- Malliaras P, Barton CJ, Reeves ND, Langberg H. Achilles and patellar tendinopathy loading programmes: a systematic review comparing clinical outcomes and identifying potential mechanisms for effectiveness. Sports Med. 2013;43(4):267-286. doi:10.1007/s40279-013-0019-z.
- Silbernagel KG, Thomeé R, Eriksson BI, Karlsson J. Continued sports activity, using a pain-monitoring model, during rehabilitation in patients with Achilles tendinopathy: a randomized controlled study. Am J Sports Med. 2007;35(6):897-906. doi:10.1177/0363546506298279.
- Docking SI, Ooi CC, Connell D. Tendinopathy: is imaging telling us the entire story? J Orthop Sports Phys Ther. 2015;45(11):842-852. doi:10.2519/jospt.2015.5880.
- Demangeot Y, Whiteley R, Gremeaux V, Degache F. The load borne by the Achilles tendon during exercise: a systematic review of normative values. Scand J Med Sci Sports. 2023;33(2):110-126. doi:10.1111/sms.14242.