Achilles tendinitis occurs when the tendon that connects the back of the leg to the heel becomes swollen and ultimately painful near the back of the heel or leg, says Dr. Funk. It is typically diagnosed as a result of “overuse” by the runner; and it is often brought about by increasing pace, distance, frequency or speed work.
Dr. Wiernik adds that pain is usually localized directly with the tendon, but it may radiate around the entire back of the ankle.
“In the early stages, runners may only feel it after their run,” he says. “As it worsens, they have pain during their run.”
If there is no swelling or bruising present, the runner is advised to work through the injury by making minor adjustments to their routine.