Achilles tendinopathy
Also called: achilles tendonitis, achilles tendinitis, achilles pain, sore achilles. Clinical name: Achilles tendinopathy (mid-portion or insertional).
Reactive Achilles flare-ups can settle in a few weeks; established tendinopathy typically takes 3–6 months of progressive calf loading. A sudden snap with weakness is a possible rupture and needs same-day care.
What it actually is
The Achilles is the biggest, strongest tendon in the body, the cable that transmits everything your calf produces into every step, hop and sprint. Achilles tendinopathy, still widely called tendonitis, is what happens when the load put through that cable outstrips its current capacity: the tendon becomes painful, often slightly thickened, and characteristically stiff for the first minutes of every morning.
The story is nearly always about change: more miles, more hills, a switch to speed work, new flatter shoes, or a return from time off. Location is worth noticing, because pain a few centimetres above the heel bone (mid-portion) and pain right at the bone (insertional) respond to slightly different rehab. What both share is the counterintuitive treatment: tendons do not recover by being rested into comfort, they recover by being loaded on purpose, progressively, for months. Slow heavy calf work is the medicine; rest alone just makes a weaker tendon with the same problem.
Two timelines deserve respect. Caught early, a reactive flare can settle in weeks. Established tendinopathy runs on tendon time, three to six months is normal, with morning stiffness as the honest scoreboard. And one moment changes everything: a sudden snap with instant push-off weakness is not tendinopathy but a possible rupture, and that is a same-day assessment, not a wait-and-see.
How bad is it?
Achilles problems are described by behaviour and location rather than grades. Reactive tendinopathy is a recently overloaded tendon: sore and often slightly thickened after a training spike, settles relatively quickly if load is managed. Persistent tendinopathy has been grumbling for months: morning stiffness, pain at the start of runs that warms up, then returns after. Location matters too: mid-portion pain (a few centimetres above the heel bone) responds well to classic loading rehab, while insertional pain (right at the heel bone) needs the programme modified. The one emergency is different in kind: a sudden snap with instant weakness is a possible rupture, not tendinopathy, and needs same-day assessment.
How long will it take?
Recovery moves in phases. This is the typical shape of it — yours may run faster or slower, and the numbers below are general ranges, not a forecast for your specific injury.
When to get it looked at
Most cases settle with time and sensible loading. Get it assessed by a professional if any of these apply — they can point to something that needs hands-on care:
- A sudden snap, pop or feeling of being kicked in the back of the ankle, with immediate weakness pushing off (possible rupture, same-day assessment)
- Unable to rise onto tiptoes on the affected leg
- A palpable gap in the tendon
- A hot, red, swollen tendon area or fever
- Pain with numbness or tingling, or symptoms not improving after three months of genuine loading rehab
This is a list of warning signs, not a diagnosis. If you are worried, or the pain is severe, see a GP, physiotherapist or urgent care.
What to track while you recover
Tendon rehab runs on months, and the day-to-day noise hides the trend. Morning stiffness scored daily is the single most honest measure an Achilles gives you, and it is the trend a clinician will ask about first.
- Morning stiffness, 0–10, in the first minutes out of bed (the key Achilles metric)
- Pain during and after runs, and the next morning
- Calf loading sessions done: sets, and the weight or difficulty level
- Running volume, surface and any hills or speed work
- Any swelling or thickening you can feel, and exactly where the tenderness sits, mid-tendon or at the heel bone
This is exactly what InjuryLog does.
Log each of these in seconds, watch the trend build day by day, and keep every scan and receipt tied to this one injury. Free on iOS, Android soon.
Wondering how long yours will take? Try the free recovery time estimator for a typical, phased timeline by injury and severity.
What to tell your physio
Achilles assessment turns on location, duration and load history. Bring the numbers: how long, how stiff in the mornings, and what training preceded it.
- Where exactly it hurts: mid-tendon or right at the heel bone (this changes the exercise plan)
- How long it has been going on, and what training change came just before it started
- Morning stiffness pattern and whether it is trending better or worse
- What loading work you have already done, honestly, including sets and weights
- Footwear, heel drop, and your running surfaces; and your target event or season
Walk in with the whole picture.
InjuryLog turns your daily logs into a clean Physio Visit Pack, a one-page summary your physio can actually read, so the first appointment starts with facts, not guesswork.
The questions people actually ask
How long does Achilles tendonitis take to heal?
A recently irritated tendon caught early can settle in a few weeks once the load spike is removed. An established tendinopathy that has grumbled for months is a longer project: meaningful improvement usually starts within six to twelve weeks of proper loading rehab, but full resolution routinely takes three to six months, because tendon remodels slowly. The mistake that stretches the timeline most is resting completely until it feels fine, then returning to full training; tendons lose capacity with rest and object to the reunion.
Can I keep running with Achilles tendonitis?
Often yes, at a managed dose, and usually better than stopping entirely. The working rule used in tendon rehab: pain up to about 3 out of 10 during activity is acceptable if it settles by the next morning and morning stiffness is not trending worse week on week. Cut hills, speed and big days first. If pain climbs during runs, lingers into the next day, or the morning stiffness is building, the dose is too high, drop back a step rather than pushing through.
Why is my Achilles stiff in the morning?
Morning stiffness is the signature symptom of Achilles tendinopathy. Overnight the tendon sits shortened and unloaded, and the irritated tissue stiffens; the first steps to the bathroom load it cold, hence the hobble that eases as it warms. It is also your best progress marker: as the tendon's capacity rebuilds, the morning stiffness fades earlier and scores lower. Tracked daily, it tells you more about whether rehab is working than any single painful run does.
What are the best exercises for the Achilles?
Progressive calf loading is the treatment with the strongest evidence: heel raises done slowly and with increasing load, building from two legs to single leg, and eventually adding weight. Mid-portion tendinopathy tolerates lowering the heel below a step; insertional tendinopathy (pain at the heel bone) generally should avoid that stretch-under-load early on and work on flat ground instead. Roughly every other day, for months rather than weeks. Passive stretching and rubbing feel productive but do not build the capacity the tendon is missing.
How do I know if my Achilles is torn rather than inflamed?
A rupture announces itself: a sudden snap or the feeling of being kicked in the back of the ankle, often audible, followed by immediate weakness pushing off and difficulty rising onto tiptoes on that leg. Some people can still walk flat-footed, which fools them into waiting. Tendinopathy, by contrast, builds gradually and never has that moment. Any sudden-snap story deserves same-day assessment, because early management of a rupture, surgical or not, materially changes the outcome.
Should I get an injection or a scan for my Achilles?
Usually neither, at least at first. The diagnosis is typically clinical, and ultrasound or MRI mostly confirms what examination already shows; imaging earns its place when a rupture or partial tear is suspected or when months of good rehab have failed. As for injections, corticosteroid around the Achilles is generally avoided because of its association with tendon weakening and rupture. The unglamorous truth is that graded loading over months outperforms the quick fixes for this tendon.
Sources
- Achilles tendinopathy — NHS
- Achilles Tendinitis — AAOS OrthoInfo