Is this Achilles tendinopathy and what should I do now

A common starting point is a “grumbly” Achilles after a run: stiffness first thing in the morning, then a tendon that eases as the ankle warms up, only to feel sorer again after faster efforts or the next day. In runners and field-sport athletes, Achilles tendinopathy often comes on gradually (over days to weeks), with pain either a few centimetres above the heel (midportion) or right where the tendon attaches at the heel bone (insertion). Morning stiffness that settles with a bit of walking is often part of the picture.

To keep the first steps easy to follow, the supporting clinical sources are kept out of the main text (rather than as distracting “code-like” brackets) and captured as standard citations.

A different pathway is needed if the symptoms sound like an acute rupture. Features that raise concern include a sudden sharp pain or a distinct “pop” in the back of the ankle/calf, immediate difficulty pushing off or walking, marked swelling or a visible change in the tendon contour, or being unable to do a single-leg heel raise on the affected side. These signs warrant urgent assessment in A&E or an emergency/urgent orthopaedic service, not a home loading programme.

If it is ongoing Achilles pain without rupture signs, it is common in active people and is usually managed without surgery—but it rarely settles with complete rest alone. Early sensible steps in the first 1–2 weeks of a flare often include:

• Temporarily reduce the highest-load triggers (fast running, hills, sprints, jumping) rather than stopping all movement.
• Keep comfortable activity going (for example, gentle walking) and introduce light, pain-limited calf loading.
• Avoid “test” sessions such as maximal efforts or sudden long runs to “see if it’s gone”.

If pain is severe, worsening over several weeks, or clearly limiting daily tasks like walking or stairs, assessment by a GP, physiotherapist, or sports clinician is often appropriate rather than waiting months. The next sections explain why load matters, how progressive strengthening is structured, and how return to sport is usually planned.

Why training load and spikes irritate the Achilles

During every running stride, the Achilles works like a strong spring that stores and releases energy. That “spring” is loaded far more than most people expect: shear-wave tensiometry studies estimate peak Achilles forces of roughly 8–10 times body weight during running, and those forces rise as running speed increases. It helps explain why sprinting, fast downhill efforts, and plyometrics (hops, jumps, bounding) so often make symptoms appear or flare.

Problems commonly start when capacity and demand stop matching—not because the tendon has “torn” in one moment, but because it is repeatedly asked to handle more load than it can currently adapt to. A simple analogy is a rope: it may not snap, but it can become painful and unreliable when it is tugged hard, too often, without time to recover and recondition. Clinical reviews describe this as tendinopathy behaving like a load-related condition where the pattern of stress matters as much as the total amount.

The most frequent “load spike” patterns tend to be very ordinary training decisions made over a relatively short period:

• A late decision to prepare for a 10 km, half marathon, or marathon, with weekly mileage rising quickly.
• Adding two speed sessions (intervals/tempo) on top of an existing running routine.
• Introducing hill sprints or repeated stair work before the calf and tendon are ready.
• Changing surface (road to track, or treadmill to road) or switching to a stiffer/new shoe, then keeping the same volume.
• Combining high-load sports in the same week (for example, keeping run volume high while adding tennis/padel, football, or basketball).

Pain location can also hint at which loads are most provocative. Midportion tendinopathy (a few centimetres above the heel) often complains after faster running and repeated push-off. Insertional pain (right on the heel bone) may be more sensitive when the ankle is forced into deep dorsiflexion—commonly felt with hills, stair descents, or calf exercises performed off a step—because that position can increase compression at the attachment.

For most active people without a rupture, the direction of travel is therefore not prolonged unloading. Contemporary reviews and guidelines emphasise that complete rest or immobilisation can reduce calf capacity further, whereas reshaping the week (reducing the highest-load triggers while building controlled strength) is usually the more effective bridge into progressive rehabilitation.

Rehabilitation built around progressive tendon loading

The centrepiece of good conservative care is a progressive tendon-loading programme rather than prolonged rest or passive treatment alone. This is consistent across contemporary reviews and the 2024 JOSPT Clinical Practice Guideline for midportion Achilles tendinopathy, which prioritise structured strengthening (with relative reduction of aggravating sport loads) as first-line management.

In practice, the two best-known strengthening “families” are eccentric calf-raise programmes and heavy slow resistance (HSR). A key randomised trial in midportion Achilles tendinopathy found that both approaches produced substantial, similar improvements in pain and function over 12 weeks, supporting the idea that the exact contraction style is usually less important than reaching an adequate, progressive load that the person can stick with (HSR had a trend towards higher satisfaction in that study).

A simple staged framework commonly used in clinics moves from settling symptoms to rebuilding capacity and then restoring sport-specific “spring” demands:

• Stage 1 (early symptom management; days to 2–3 weeks): relative reduction of provocative running/jumping, plus isometrics or supported calf raises in a comfortable range. The goal is maintaining some load without repeatedly triggering next-day flares.
• Stage 2 (strength rebuilding; often weeks 2–8): heavier calf strengthening (eccentric and/or HSR), progressing load, sets and range of motion as tolerated.
• Stage 3 (energy-storage; often weeks 6–12+): faster, elastic work such as skipping, hops and small jumps to reintroduce high-rate tendon loading.
• Stage 4 (sport-specific return): drills that match the sport—progressing from controlled running to faster running, change-of-direction and higher jumps—while watching symptom behaviour across 24 hours.

A typical “arc” for a runner (example only) might be: Week 1 focuses on removing the sharpest triggers (for example, hills/sprints) while introducing short bouts of low-load calf work; by Week 6, the same runner is often doing heavier calf raises with planned recovery days and may be trialling controlled, flatter running alongside strengthening—still avoiding the biggest spikes until later-stage energy-storage work is tolerated. The exact dosing varies, but programmes commonly separate genuinely heavy tendon-loading sessions with planned recovery.

Pain-monitoring is commonly used to steer progression. Many protocols allow some discomfort during/after exercise (often described as mild–moderate on a 0–10 scale) provided symptoms settle reasonably within 24 hours, morning stiffness does not clearly worsen, and there is no week-to-week drift towards higher baseline pain. A repeated pattern of “pushing through” followed by multi-day flares is usually a sign that load is outpacing current capacity and needs adjusting. Adjuncts (for example, taping or manual therapy) may be used to support the loading plan, but the strongest consistent emphasis remains on progressive strengthening as the main driver of recovery.

No single rep scheme or weekly progression has been proven “best” across all athlete types; the clearer evidence-based principle is the direction: graded, progressive load that is reviewed and adjusted based on symptoms and function.

Planning a graded return to running and sport

Getting back to “proper” running or match play after Achilles tendinopathy is best handled as a criteria-led decision, not a calendar date. Contemporary guidance notes that published timelines vary widely depending on symptom duration and the demands of the sport.

The two signals that tend to carry the most weight

In day-to-day sports medicine practice, two “go/no-go” signals often guide progression more than any single test score: (1) next-day symptom behaviour (especially morning stiffness) and (2) calf capacity compared with the other side. Both are emphasised in clinical guidance as practical ways to titrate and progress load.

Common checkpoints before running becomes “training” again

A typical set of return-to-running / return-to-sport benchmarks combines symptoms, strength/endurance, and tolerance of spring-like tasks:

• Morning symptoms: minimal or no morning stiffness on waking over a 24-hour cycle.
• Everyday function: low pain with walking and stairs (i.e., day-to-day activity is no longer the main irritant).
• Strength/endurance: near-symmetry on calf tests—often around 90% of the other side on single-leg heel-rise measures.
• Energy-storage tolerance: the ability to perform hopping or similar drills and have no clear symptom flare in the following 24 hours.

A representative graded return-to-running structure

Return-to-running progressions are commonly described as starting conservatively and building in steps: walk–run intervals on flat ground at an easy pace, then gradual increases in total running time before any meaningful increase in intensity. A common practical rule is to change one variable at a time (duration first, then speed, then hills/uneven terrain), leaving enough time to judge next-day response before advancing again.

Field, court, and jumping sports: the “middle” is where relapses happen

For football, rugby, netball, basketball, or racket sports, return rarely stops at continuous running: progressions usually add controlled accelerations and decelerations, then cutting and jumping/landing drills, before the final step into full training and competitive match play. Guidance for midportion Achilles tendinopathy highlights that restoring muscle power and energy-storage capacity is part of late-stage rehabilitation, which aligns with this staged reintroduction of higher-rate loads.

Why a longer plan is often realistic, even when pain improves early

Achilles tendinopathy is common in high-load sport, and clinical guidance notes that recovery can be prolonged in some people—particularly when symptoms have been present for longer or sport demands are high—so calendar pressure (a race block or season) often needs to be weighed against the tendon’s next-day behaviour and objective calf capacity.

When to see a specialist and what assessment involves

Escalation beyond self-management or routine physiotherapy is most useful when the diagnosis is uncertain, progress stalls despite a structured loading plan, or the pattern of pain suggests something more acute than tendinopathy. In line with that, the next step is typically an opinion from a sports-medicine or foot-and-ankle specialist (via NHS or private services), rather than a route tied to any single clinic or treatment.

Urgent problems (possible rupture)

A different pathway applies when symptoms start with a sudden sharp pain or a felt/heard “pop” at the back of the ankle, followed by immediate difficulty walking or pushing off, marked swelling, or an obvious change in tendon contour. In that setting, urgent assessment (A&E / emergency orthopaedics) is usually advised, because an acute rupture needs prompt diagnosis and management.

Persistent or complex cases

For tendinopathy-type symptoms, a specialist review is often reasonable when pain persists despite a well-structured, progressive loading programme, when work or day-to-day walking remains significantly limited, when repeated flares occur during attempted progression, or when the clinical picture is unclear (for example, distinguishing midportion from insertional problems or excluding a partial tear).

What to expect at a specialist review

Assessment commonly starts with a detailed history of symptom behaviour and recent training-load changes, followed by examination for local tenderness and thickening, plus calf strength/endurance measures (often using repeated single-leg heel raises) and higher-load functional tasks such as hopping when appropriate. Imaging—usually ultrasound, sometimes MRI—may be used to support the diagnosis, check for alternative pathology (including partial tearing), and guide planning; imaging findings are generally treated as one part of the picture rather than a stand-alone measure of “severity”.

Where injections and biologics fit

If symptoms persist after several months of optimised, supervised loading-based rehabilitation, some clinicians discuss injections or biologic options (for example PRP) as possible adjuncts; however, reviews describe the evidence base as limited and heterogeneous, and no single biologic approach can currently be considered standard care for Achilles tendinopathy.

In London, assessment is available through NHS foot-and-ankle services and private sports-medicine clinics; one option is the London Cartilage Clinic (Harley Street), which focuses on specialist MSK assessment and joint-preservation decision-making when straightforward rehabilitation is not settling symptoms.

Long term outlook, prevention, and next steps

Long-term progress with Achilles tendinopathy tends to be measured in months, because tendon capacity and calf strength take time to rebuild. Many active people improve substantially with a dedicated strengthening plan, but returning to previous training loads and confidence can still take longer in some cases—particularly when symptoms have been present for a long time or when sport demands repeated sprinting/jumping.

Recurrence is more likely when training returns rapidly to previous volumes and intensity while calf capacity is still lagging, which is one reason guidance cautions against an overly quick return to full sport. The 2024 JOSPT CPG also keeps the focus on restoring not only pain control, but muscle power and energy-storage capacity, so that the tendon can tolerate higher-rate loads again.

Three prevention principles that tend to hold up across sports are:

• Keep some calf strengthening “in-season” even once symptoms have largely settled.
• Introduce training changes (volume, speed, hills, a new class) gradually, rather than stacking several increases in the same 7-day period.
• Use next-day signs—especially morning stiffness or a clear 24-hour flare after harder sessions—as an early warning to hold or reduce load.

A mild, familiar “awareness” in the tendon during heavier training does not necessarily mean damage or treatment failure; the more concerning pattern is a sudden step-up in pain, stiffness that persists across several mornings, or new loss of push-off strength. To close on a practical next step (rather than focusing on any single clinic): the most useful habit is to keep one objective marker (for example, morning stiffness and a simple calf-capacity test) and adjust the week’s training accordingly. If diagnosis is uncertain, progress has plateaued, or a higher-level return-to-sport plan is needed, an individualised assessment can be arranged at the London Cartilage Clinic (Harley Street) via londoncartilage.com, with coordination alongside a local physiotherapist where appropriate.

1. [1] Achilles tendinopathy. (2025). https://doi.org/10.1038/s41572-025-00602-9 https://doi.org/10.1038/s41572-025-00602-9