Post-exercise Achilles tendon pain refers to pain in the Achilles tendon area after exercise, and common causes include over-exercise, Achilles tendonitis, Achilles tendon injury, and posterior Achilles tendon bursitis. 1. Excessive exercise: If there is no sufficient warm-up before exercise, and a large amount of lactic acid accumulates in the muscles after exercise, pain in the Achilles tendon area can occur, which is a normal phenomenon. 2. Achilles tendonitis: due to the Achilles tendon repeated pulling injury, trauma and other reasons, caused by the Achilles tendon of the aseptic inflammatory reaction, will also appear in the Achilles tendon pain. 3. Achilles tendon injury: due to improper posture in sports, resulting in excessive flexion of the ankle joint, the Achilles tendon is damaged or even ruptured under the strong traumatic effect, and obvious pain can occur. 4. Posterior bursitis of Achilles tendon: due to ill-fitting shoes, mountaineering, long-distance running, etc., repeated mechanical friction stimulation of the heel, causing aseptic inflammation of the posterior bursa of the heel, pain can also occur, similar to the site of pain in the Achilles tendon. Causes of pain in the area of the Achilles tendon after exercise are more reasons, and may also be related to the Achilles bone fracture and other diseases, if the symptoms continue to be unrelieved, it is recommended to consult a doctor in a timely manner, to clarify the cause of the disease, and to carry out targeted treatment.