Achilles tendinopathy is a serious condition that often affects runners. Through frequent impact and flexing, the load placed on the Achilles tendon can cause repeat injuries. As time goes by, the tissue starts failing to catch up with damage. When this happens, the structure of the tendon can start to change—if left unchecked, this can result in significant pain and mobility issues.

Achilles tendinopathy can be treated, but treatment needs to happen sooner rather than later. As such, runners should look out for the following four common symptoms and see a podiatrist if they present themselves.

1. Pain

By far the most common symptom of Achilles tendinopathy is pain around the ankle. It won't occur suddenly—if you do notice sudden pain in your ankle, you've probably torn or ruptured the tendon. Achilles tendinopathy is equally deserving of medical attention, but pain will be experienced more gradually. You'll almost certainly feel more tender across the ankle after a long run, especially if you needed to power up lots of hills, and you may also experience more pain in the morning before you've had a chance to loosen up.

2. Stiffness

Stiffness is another common sign of Achilles tendinopathy, and it's another one that tends to occur more frequently at certain times of day. Your Achilles tendon will often feel stiff when you first get up or when you've been sitting in the same position for some time.

3. Thickness or Swelling

Achilles tendinopathy often involves a thickening or swelling around the ankle, though this is sometimes quite hard to spot. It occurs when repetitive damage causes the muscle tissues to grow dense. If you run your fingers along the Achilles tendons, you may notice that the problem ankle feels a little thicker. Swelling can occur throughout the day, but it should get worse after you've exercised.

4. Odd Noises

You might not have heard of crepitus, but you might have heard it if you suffer from Achilles tendinopathy. It's a medical term used to describe grating, crackling, popping or creaking sounds as a joint is moved. Such sounds may also be accompanied by a similar sensation beneath the skin. It can be caused by several conditions, including Achilles tendinopathy. Where the tendon is tender, you may hear or feel a rough grating or creaking when you move the ankle up and down—this is caused by the development of fibrous tissues within the Achilles tendon.