⚠ Clinical Note
This article is for educational purposes only. It is based on current clinical practice guidelines and peer-reviewed research and is not a substitute for personalised medical advice, diagnosis, or treatment. If you have Achilles pain or any concerns about your symptoms, consult a qualified healthcare professional before starting any exercise or treatment program.

Key Facts
✔ Achilles tendinopathy affects 4–7% of the general population and is particularly common in runners and active individuals [1]
✔ The primary evidence-based treatment is progressive tendon loading exercise-not rest [1, 2]
✔ Two distinct presentations exist-midportion and insertional-and they require different treatment approaches [1]
✔ A sudden pop with inability to weight bear may indicate rupture and requires urgent medical assessment [3]
✔ High-intensity laser therapy has demonstrated benefit as an adjunct to exercise-based rehabilitation [4]
✔ Most people improve significantly with appropriate physiotherapy-surgery is rarely required [1]

30-Second Summary

Achilles tendinopathy is pain and reduced function in the Achilles tendon, most commonly caused by a sudden increase in training load. The most important thing to understand is that rest alone does not resolve it-progressive loading exercise is the evidence-based first-line treatment. Where you feel the pain along the tendon matters significantly for how it should be treated. A physiotherapy assessment is the right starting point.

What Is Achilles Tendinopathy?

The Achilles tendon connects the calf muscles-the gastrocnemius and soleus-to the heel bone (calcaneus). It is the thickest and strongest tendon in the body, yet it is also one of the most commonly injured in active people.

Achilles tendinopathy refers to pain, stiffness and reduced function in the tendon, associated with loading activities such as walking, running and jumping.

Definition: Tendinopathy-a clinical diagnosis of tendon pain and dysfunction in response to mechanical load. The term is preferred over "tendinitis" in current guidelines because it avoids assuming inflammation is the primary cause-the underlying pathology is more complex than early research suggested. [1]

Midportion vs Insertional: Why the Location Matters

This is one of the most clinically important distinctions in Achilles tendinopathy, and one that is frequently not explained to patients.

Midportion Achilles tendinopathy refers to pain located more than 2 cm above the heel bone, in the middle section of the tendon. This is the most common presentation and the one with the strongest evidence base for exercise-based rehabilitation [1].

Insertional Achilles tendinopathy refers to pain at or near the point where the tendon attaches to the heel bone. This presentation has a different pain mechanism and responds differently to treatment. Importantly, the heel drop exercises commonly recommended for midportion tendinopathy-which involve moving the ankle into a fully stretched position-can increase compressive load at the insertion point and may aggravate insertional presentations [1, 5].

Why this matters for you: If you have been given a standard Achilles exercise program and it is not helping-or making things worse-the location of your pain may explain why. A proper assessment determines which type you have before treatment begins.

The 2024 Clinical Practice Guideline for midportion Achilles tendinopathy explicitly notes that its recommendations do not generalise to insertional presentations, and directs clinicians to separate guidelines for that condition [1].

What Causes Achilles Tendinopathy?

The primary cause is tendon overload-when the load placed on the tendon exceeds its capacity to adapt [1, 2].

Training load errors are the most common trigger. A sudden increase in running volume, training intensity or frequency-particularly in runners returning after a break-is the classic presentation. The tendon cannot adapt quickly enough to the increased demand [2, 6].

Other contributing factors identified in the research include:

• Reduced ankle dorsiflexion (limited upward movement of the foot), which increases tendon stress [1]
• Reduced calf muscle strength and power [1]
• Previous Achilles tendinopathy-a history of the condition is associated with higher recurrence risk [1]
• Sudden changes in footwear or running surface [6]
• Increased age, as tendon tissue properties change over time [1]
• Certain medications-particularly fluoroquinolone antibiotics-are associated with increased tendon vulnerability. If you have recently taken this class of antibiotics and developed Achilles pain, mention this to your clinician [1]

What does not cause it: Achilles tendinopathy is not caused by a single traumatic event in most cases. It is an overuse pattern-which means recovery is also gradual. There is no shortcut.

Symptoms: What Does Achilles Tendinopathy Feel Like?

The symptoms of Achilles tendinopathy are recognisable - but they are also easy to dismiss early on, which is why many people present for assessment after the condition has already become chronic.

Morning stiffness is one of the most consistent early signs. The back of the ankle feels stiff and painful with the first steps of the day, typically easing after 5–10 minutes of movement. This pattern - pain that worsens with initial loading then improves - is characteristic of tendinopathy [1].

Pain during and after activity is the other hallmark. Typically the tendon feels uncomfortable at the start of a run, may ease during the middle of the session, then becomes sore again afterwards. As the condition progresses, pain may be present throughout activity and into the following day [1].

Tendon thickening is often visible or palpable - a fusiform (spindle-shaped) swelling in the midportion of the tendon approximately 2–6 cm above the heel. This is a structural change associated with the condition and is not an indicator of severity alone [1].

Tenderness on palpation - direct pressure on the tendon, particularly the midportion, reproduces localised pain. This is one of the key diagnostic features used in clinical assessment [1].

What tendinopathy does not typically feel like:

• A sudden sharp onset with immediate inability to walk (this pattern is more consistent with rupture - see the rupture section below)
• Pain that is completely unrelated to activity or loading
• Widespread leg or calf pain rather than localised tendon pain

If your symptoms do not match this pattern, a physiotherapy assessment will determine the correct diagnosis

How Is Achilles Tendinopathy Diagnosed?

Diagnosis is clinical-based on history and physical examination. The key diagnostic features according to the 2024 Clinical Practice Guidelines are [1]:

• Pain localised to the Achilles tendon
• Pain provoked by tendon-loading activities (walking, running, jumping)
• Pain with direct palpation of the tendon
• Tendon thickening where present

Imaging (ultrasound or MRI) is not routinely required for diagnosis and does not change initial management in most presentations. Structural changes visible on imaging do not always correlate with pain or function [1].

The VISA-A questionnaire (Victorian Institute of Sport Assessment-Achilles) is the most widely used patient-reported outcome measure for Achilles tendinopathy. It is a score out of 100-higher is better-measuring pain and ability to perform daily and sporting activities. Your physiotherapist may use it at assessment and throughout your rehabilitation to track progress objectively [1].

Is It a Rupture? When to Seek Urgent Assessment

Achilles tendinopathy must be distinguished from Achilles tendon rupture, which is a different and more serious condition requiring urgent medical assessment.

Signs that may indicate a rupture-seek urgent care:

• A sudden sharp pain at the back of the ankle, often described as a snap or pop
• Inability or significant difficulty bearing weight immediately after
• A visible gap or depression in the tendon
• Positive Thompson test: when the calf is squeezed with the patient lying face down, the foot does not move as expected [3]

If you experience any of these signs, do not wait for a physiotherapy appointment-attend an emergency department or urgent care facility.

Tendinopathy, by contrast, develops gradually over days to weeks, and weight bearing-while painful-remains possible.

What the Evidence Recommends for Treatment

1. Progressive Tendon Loading Exercise-First-Line Treatment

The 2024 Clinical Practice Guideline is explicit: clinicians should use tendon loading exercise as a first-line treatment to improve function and decrease pain for individuals with midportion Achilles tendinopathy [1]. Loading is progressed based on the individual's pain tolerance and functional capacity-not forced through severe pain.

The evidence supports a structured progression through three stages [1, 2, 7]:

Stage 1-Isometric Loading
Purpose: Pain management and early tendon stimulation.
What it involves: Sustained calf contractions held at a fixed ankle position for approximately 45 seconds, repeated 4–5 times. Useful in the acute phase and for managing pain during periods of higher training load [1, 8].
Patient example: Standing on one leg and holding a calf raise position against a wall without moving through range.

Stage 2-Isotonic Loading (Heavy Slow Resistance)
Purpose: Tendon remodelling and capacity building.
What it involves: Slow, controlled heel raises and lowering-both the upward (concentric) and downward (eccentric) phases performed at a deliberate tempo. The Alfredson eccentric protocol (3 sets of 15 repetitions, twice daily, over 12 weeks) has the longest evidence base [2, 6]. Heavy slow resistance training (3 sets of 15 repetitions, 3 times per week, over 12 weeks) has demonstrated equivalent outcomes with better patient adherence in some studies [7].

Stage 3-Plyometric and Sport-Specific Loading
Purpose: Power restoration and return to full activity.
What it involves: Progressive introduction of dynamic loading-for example, progressing from walking to jogging, then running, then sport-specific movements as pain and function allow [1].

Important: The exercise parameters above are drawn from the referenced research studies. Your physiotherapist determines the appropriate starting point and rate of progression for your individual presentation. These are not self-prescription guidelines.

2. What About Rest?

Complete rest is not recommended and is not supported by the evidence [1, 2]. Activity modification-reducing the load that aggravates the tendon while maintaining general fitness-is appropriate in the acute phase. The tendon needs load to adapt and recover. Prolonged rest leads to tendon deconditioning and does not address the underlying capacity deficit.

3. High-Intensity Laser Therapy as an Adjunct

For presentations not responding adequately to exercise alone, or where pain is limiting the ability to load appropriately, high-intensity laser therapy (HILT) has demonstrated benefit as an adjunct treatment [4].

HILT stimulates photobiomodulation at depth-promoting anti-inflammatory effects, cellular tissue repair and pain modulation in a structure not well reached by surface-level modalities [4].

At RheCore, HILT is considered for Achilles tendinopathy presentations where clinical assessment indicates it may support the exercise rehabilitation process. It is used alongside progressive loading exercise-not as a replacement for it. The research does not support laser therapy as a standalone treatment for tendinopathy [4].

4. Shockwave Therapy

Extracorporeal shockwave therapy has evidence supporting its use in chronic Achilles tendinopathy that has not responded to conservative management [9]. It is considered for persistent presentations following an adequate trial of loading exercise.

5. What the Evidence Does Not Support

• Corticosteroid injections-associated with short-term symptom relief but no long-term benefit, and potential tendon weakening with repeated use [1]
• Passive modalities alone (ultrasound, heat, massage without exercise)-insufficient as standalone treatments [1]
• Complete rest-counterproductive for tendon recovery [1, 2]

Self-Management: What You Can Do Now

These strategies are appropriate while you are waiting for a physiotherapy assessment or between appointments. They are not a substitute for a structured rehabilitation program - but they can help manage symptoms and avoid making things worse.

Modify your load - do not stop completely
Reduce the activity that is aggravating your tendon - typically running volume or intensity - but maintain general movement and fitness where possible. Complete rest is not recommended and does not address the underlying problem [1, 2]. A useful guide: if your pain is above 3 out of 10 during or after activity, or has not settled by the following morning, the load was too high and should be reduced further.

Avoid stretching the Achilles into full range
Sustained stretching of the Achilles tendon - particularly deep calf stretches with the heel dropping below a step - is not recommended in the early stages of tendinopathy and may aggravate symptoms, particularly in insertional presentations [1, 5]. This is counterintuitive for many people who associate stretching with recovery, but the evidence does not support it as a primary management strategy for this condition.

Footwear considerations
A small heel lift (approximately 1 cm) inside your shoe can reduce the load placed on the Achilles tendon during daily walking. This is a short-term strategy to manage symptoms - not a long-term solution - and should be discussed with your physiotherapist [6].

Manage activity timing
If you need to maintain some running or sport, shorter sessions with adequate recovery time between them are preferable to fewer, longer sessions. The tendon needs time to respond to load - spacing activity across the week supports this [1].

Monitor your 24-hour response
A practical guide used in tendinopathy rehabilitation: assess how your tendon feels the morning after activity. If symptoms are the same or better than the day before, the load was appropriate. If symptoms are worse, reduce the load at your next session [1, 6].

What to avoid:

• Sudden spikes in training volume or intensity
• Consecutive days of high tendon load without recovery
• Running on hard surfaces without adequate footwear support if symptoms are active
• Ignoring symptoms that are progressively worsening over weeks

Returning to Running and Sport

Return to running is guided by function, not by time alone [1]. General principles supported by the evidence:

• Pain during or after activity should remain at or below a manageable level-typically 0–3 out of 10 on a pain scale-and should settle within 24 hours of loading [1, 6]
• Single-leg heel raise capacity should be comparable to the unaffected side before return to full running volume [1]
• Return should follow a structured gradual progression rather than resuming previous volume immediately [6]

Your physiotherapist will assess your specific readiness based on these criteria alongside your individual goals and activity demands.

When Should You See a Physiotherapist?

A physiotherapy assessment is appropriate if:

• You have pain at the back of the ankle provoked by walking, running or exercise
• You experience morning stiffness at the back of the ankle that takes more than a few minutes to ease
• You have tried rest and pain keeps returning when you resume activity
• You are a runner or active person wanting to return to sport after Achilles pain
• You have been told you have Achilles tendinopathy but are not improving with your current management

Seek urgent medical assessment-not a physiotherapy appointment-if you experience a sudden pop, inability to weight bear, or any of the rupture signs described above.

Key Takeaways

• Achilles tendinopathy is an overuse condition caused by tendon overload-most commonly from a sudden increase in training [1, 2]
• Midportion and insertional are different conditions requiring different treatment-knowing which type you have matters [1]
• Progressive tendon loading exercise is the evidence-based first-line treatment-not rest [1, 2]
• A sudden pop with inability to weight bear may indicate rupture and requires urgent medical assessment [3]
• HILT and shockwave therapy have evidence supporting their use as adjuncts to exercise rehabilitation in appropriate presentations [4, 9]
• Most people improve significantly with appropriate physiotherapy-seek assessment early

References

[1] Chimenti RL, Neville C, Houck J, Cuddeford T, Carreira D, Martin RL. Achilles pain, stiffness, and muscle power deficits: midportion Achilles tendinopathy revision – 2024: clinical practice guidelines. Journal of Orthopaedic and Sports Physical Therapy. 2024;54(12):CPG1-CPG32. doi:10.2519/jospt.2024.0302

[2] 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 for midportion Achilles tendinopathy. Orthopaedic Journal of Sports Medicine. 2023. doi:10.1177/23259671231171178

[3] Thompson TC. A test for rupture of the tendo achillis. Acta Orthopaedica Scandinavica. 1962;32:461–465

[4] Arroyo-Fernández R, Aceituno-Gómez J, Serrano-Muñoz D, Avendaño-Coy J. High-intensity laser therapy for musculoskeletal disorders: a systematic review and meta-analysis of randomized clinical trials. Journal of Clinical Medicine. 2023;12(4):1479. doi:10.3390/jcm12041479

[5] Insertional Achilles tendinopathy-Dutch multidisciplinary guideline [referenced in Chimenti et al. 2024 as the appropriate resource for insertional presentations]

[6] Alfredson H, Pietilä T, Jonsson P, Lorentzon R. Heavy-load eccentric calf muscle training for the treatment of chronic Achilles tendinosis. American Journal of Sports Medicine. 1998;26(3):360–366

[7] Beyer R, Kongsgaard M, Hougs Kjær B, Øhlenschlæger T, Kjær M, Magnusson SP. Heavy slow resistance versus eccentric training as treatment for Achilles tendinopathy: a randomized controlled trial. American Journal of Sports Medicine. 2015;43(7):1704–1711

[8] Rio E, Kidgell D, Purdam C, et al. Isometric exercise induces analgesia and reduces inhibition in patellar tendinopathy. British Journal of Sports Medicine. 2015;49(19):1277–1283

[9] Liu K, Zhang Q, Chen L, et al. Efficacy and safety of extracorporeal shockwave therapy in chronic low back pain: a systematic review and meta-analysis. Journal of Orthopaedic Surgery and Research. 2023;18:455