The Achilles tendon is located at the back of the lower leg and connects the calf muscles to the heel bone. It plays a vital role in movement, allowing us to walk, run, jump, stand on our toes, and absorb impact during daily activities. At approximately 15 cm in length, it is the strongest tendon in the human body and is essential for proper foot and ankle function.
Pain is most commonly felt where the Achilles tendon attaches to the back of the heel bone. In the early stages, the tendon may feel stronger during activity, but over time it becomes weaker and more vulnerable to damage. The main symptoms include pain, stiffness, and visible thickening of the tendon. Discomfort often worsens after activity rather than during it, and the tendon may feel hard or tight the following day.
Why the Term “Tendinosis” Is Used
The term tendinitis is no longer widely used because the suffix “-itis” implies inflammation. Research has shown that chronic Achilles tendon problems are typically degenerative rather than inflammatory. For this reason, the correct term is Achilles tendon tendinosis, which describes a long-term deterioration of tendon fibers due to overuse and insufficient recovery.
Tendinosis develops when acute irritation is not properly treated. Over time, the tendon fibers begin to break down, scar tissue forms, and permanent thickening may occur. Some individuals even report a grinding sensation within the tendon.
Tendinosis can appear:
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At the tendon’s attachment to the heel bone (often associated with Haglund’s deformity)
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At the junction where the tendon meets the muscle (myotendinosis)
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Along the tendon itself
What Causes Achilles Tendinosis?
Achilles tendinosis is considered an overuse injury. It develops due to repeated stress placed on the tendon during walking and running, especially when combined with predisposing internal and external factors.
Internal (anatomical and physical) factors include:
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Flat feet or dropped arches
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Excessive foot pronation during walking or running
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Muscle imbalance between strength and flexibility
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Reduced tendon elasticity with age
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Limited blood supply to the middle third of the tendon (a key contributing factor)
External factors include:
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Hard running surfaces such as asphalt
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Frequent changes in terrain
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Sudden increases in training intensity or duration
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Worn-out or inappropriate sports footwear
Unsuitable shoes are one of the most common and preventable causes of Achilles overload.
Self-Help and Early Care
At the first signs of discomfort, activity modification is essential. Running and other high-impact exercises should be reduced or temporarily stopped.
Helpful measures include:
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Placing a 1–2 cm heel lift in both shoes to reduce tendon strain
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Wearing supportive footwear in everyday activities, not just during sports
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Performing gentle passive stretching exercises
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Applying ice to the painful area 4–5 times per day for 10 minutes (never directly on the skin and without massage)
Choosing proper footwear is critical in both recovery and prevention. Shoes with adequate cushioning, heel support, and pressure distribution reduce strain on the Achilles tendon. DrLuigi® footwear is designed with soft uppers and shock-absorbing soles that help minimize heel impact and support natural foot alignment. By reducing excessive stress during daily movement, DrLuigi® models contribute to long-term tendon health and comfort.
When to See a Doctor
Although early self-care can relieve symptoms, professional evaluation is strongly recommended. Identifying all contributing factors—biomechanical, training-related, and footwear-related—is essential for successful treatment. Without proper management, Achilles tendinosis can become chronic and significantly limit mobility.
Early diagnosis, supportive footwear such as DrLuigi®, and gradual return to activity are key to protecting the strongest tendon in the body and maintaining pain-free movement.
