Astym® Compared Eccentric Exercise for Chronic Mid-substance Achilles Tendinopathy

The purpose of this study is to compare the changes in pain and self-perceived function between two different treatments for Achilles tendinopathy: the Astym® protocol (a form of soft tissue mobilization using instruments) and a specific exercise protocol that involves strengthening the calf and Achilles tendon. Astym® (A-stim) is not an acronym, but rather stands for "A Stimulation" of the body's healing response, describing the physiologic process which occurs with Astym treatment. Astym is the trademark name of a non-invasive treatment where instruments are applied topically to locate unhealthy soft tissue, and to transfer mild to moderate pressure to the underlying soft tissue structures. The aim of Astym treatment is to eliminate scar tissue and stimulate tissue regeneration. Both the principal investigator and co-investigator have been trained and certified in administering the Astym treatment. The specific exercise protocol will involve exercises that strengthen the Achilles and calf through eccentric exercise. Eccentric exercise is a form of exercise where the benefit comes from applying a controlled lengthening stress to the muscle and tendon.