Definition
Achilles tendonitis is inflammation or degeneration of the Achilles tendon, which connects the calf muscles to the heel bone. Common triggers: increasing speed or distance too quickly, suddenly adding hills or stair climbing, doing too much too soon after time off, a violent calf contraction (an all-out sprint), general overuse, and tight calf muscles.
Risk Factors
Improper or worn-out footwear. Skipping the warmup. Inflexible calf muscles. Skipping the cooldown. A poorly designed training program.
Symptoms
Tenderness 1 to 2 inches above where the tendon attaches to the heel bone, most noticeable on rising in the morning. Stiffness that eases as the tendon warms up. Pain after activity that gradually worsens. Localized or radiating pain along the tendon during or after running. Swelling over the Achilles.
Diagnosis
X-rays to check for calcium in the tendon. MRI to view interior tendon damage.
Treatment
Rest. Break from the activity that caused it. Switch to something that spares the tendon, like swimming.
Orthoses. A shoe insert can position the foot correctly for walking and running.
Physical therapy. Stretching, massage, and strengthening, with eccentric (lengthening) calf loading as the best-supported exercise. Exercise therapy carries the highest level of evidence, and guidelines recommend a trial of at least about 3 months before considering other options (AAOS OrthoInfo).
Medications. NSAIDs ease pain and inflammation. They are not curative and must be paired with the other measures.
Prevention
Warm up and cool down properly. Wear footwear appropriate for the sport. Replace shoes before they wear out (how often depends on training frequency, the surface, and the conditions). Add hills, stairs, speed, and distance gradually. Stretch and strengthen the calves regularly.
Frequently Asked Questions
What causes Achilles tendonitis?
It is an overuse injury. The tendon is irritated or degenerates when load rises faster than it can adapt, for example ramping up speed or distance too quickly, adding hills or stairs, returning too hard after time off, or training in worn-out shoes with tight calves (AAOS OrthoInfo).
What does Achilles tendonitis feel like?
The classic complaint is heel-cord pain and stiffness that is worst on the first steps in the morning and eases as the tendon warms up. Patients also notice tenderness 1 to 2 inches above the heel, pain that worsens after activity, and sometimes swelling along the tendon.
How is Achilles tendonitis treated?
Most cases respond to conservative care: rest from the aggravating activity, switching to low-impact exercise like swimming, calf stretching and eccentric strengthening, supportive footwear or orthoses, and NSAIDs for short-term pain relief. Exercise therapy has the strongest evidence and is usually tried for at least 3 months first (AAOS OrthoInfo).
Why is eccentric exercise emphasized?
Eccentric loading (contracting the calf while it lengthens) is the best-studied exercise for midportion Achilles tendinopathy and helps the tendon remodel. It should be learned under a therapist's guidance at first, because doing it incorrectly can aggravate the tendon.
Do NSAIDs cure Achilles tendonitis?
No. NSAIDs ease pain and inflammation but are not curative and must be paired with rest, footwear correction, and a loading program. Relying on medication alone lets the underlying training error continue.
How can patients prevent it from coming back?
Warm up and cool down, increase distance, speed, and hills gradually, replace worn shoes, and keep the calves flexible and strong. Correcting the training error that caused the flare is the part patients most often skip.