Achilles Tendinopathy: Causes, Symptoms, Treatment, and Specific Considerations in Athletes

What Is Achilles Tendinopathy?

Achilles tendinopathy refers to painful and degenerative changes within the Achilles tendon. Unlike classic inflammation, this condition typically results from chronic overload on the tendon, rather than an acute inflammatory response.

The Role of the Achilles Tendon

The Achilles tendon is the strongest tendon in the human body. It connects the calf muscles to the heel bone and is essential for several movements, including:

• Walking

• Running

• Jumping

• Acceleration and changing direction

When the mechanical load on the tendon exceeds its ability to adapt, microdamage occurs. This can cause thickening of the tendon, structural alterations, and discomfort.

Main Causes of Achilles Tendinopathy

• Sudden increase in training volume

• Running on hard surfaces

• Wearing inappropriate footwear

• Limited ankle mobility

• Weakness in the calf muscles

• Excess body weight

• Sedentary work combined with bursts of high-intensity activity

Ultimately, Achilles tendinopathy is a problem of load management.

Symptoms

• Pain located 2–6 cm above the heel bone

• Morning stiffness

• Tendon thickening

• Tenderness when palpated

• Increased pain after activity

It is important to note that if pain decreases during warm-up but returns after exercise, this signals continued overload of the tendon.

Types of Achilles Tendinopathy

1. Mid-portion tendinopathy: The most common type, occurring 2–6 cm above where the tendon inserts into the heel bone.

2. Insertional tendinopathy: Located at the attachment of the tendon to the heel bone.

Treatment approaches are tailored slightly depending on the specific type involved.

Diagnosis

• Clinical examination

• Functional testing

• Ultrasound imaging

• MRI when necessary

For most cases, a comprehensive clinical assessment is sufficient for diagnosis.

Achilles Tendinopathy in Athletes

Why Are Athletes at Higher Risk?

In athletes, the Achilles tendon is exposed to repetitive, explosive loading, accelerations and sudden stops, high plyometric demands, and large running volumes. Insufficient recovery also contributes to increased risk. This condition is especially common in:

• Football players

• Track and field athletes

• Basketball players

• CrossFit athletes

• Tennis players

Common Mistakes in Athletes

• Continuing to train or compete despite pain

• Relying solely on nonsteroidal anti-inflammatory drugs (NSAIDs)

• Performing aggressive stretching

• Returning to play prematurely

• Neglecting structured strength training

Pain that "warms up" during activity does not indicate that the tendon has healed.

Modern Treatment Approach

• ❌ Complete rest is not recommended

• ❌ Topical treatments and medications alone are inadequate

• ❌ Ignoring symptoms increases the risk of rupture

• ✔ Load management is essential

• ✔ Isometric exercises help modulate pain

• ✔ Eccentric loading is beneficial

• ✔ Heavy slow resistance training aids recovery

• ✔ Gradual progression with plyometric exercises is advised

• ✔ Correcting biomechanical issues is important

• ✔ Weight management where needed

• ✔ Adjunctive physiotherapy modalities can support recovery

Controlled and progressive loading of the tendon is necessary for healing, rather than complete rest.

Return to Play Criteria

Returning to sport is appropriate when:

• Morning stiffness is absent

• No tenderness is present when palpating the tendon

• The athlete can perform 20–25 single-leg heel raises without pain

• Plyometric exercises are tolerated without symptoms

Recovery Timeline

• Mild cases usually recover in 4–6 weeks

• Chronic cases may require 8–12 weeks

• If overload is left untreated, there is a risk of partial or complete tendon rupture

The biology of tendon adaptation cannot be rushed; proper guidance is essential for recovery.

When to Seek Urgent Medical Attention

• Sudden "pop" in the heel area

• Inability to stand on tiptoe

• Sudden, sharp increase in pain

These signs may indicate an Achilles tendon rupture and warrant immediate medical evaluation.

Key Takeaway

Achilles tendinopathy is not a minor strain that will simply disappear on its own. It is a warning sign that mechanical load is exceeding tissue capacity. Successful management requires a systematic progression, patience, and intelligent control of training loads.