There is some evidence that performing slow extended movements during exercise may help chronic tendon injuries heal. For example, a study in the Journal of Shoulder and Elbow Surgery discovered that six weeks of slow eccentric exercise improved strength and reduced pain and tenderness in people with chronic tennis elbow injuries better than conventional treatment (e.g., massage, ultrasound, and heat/ice application). Be sure to be careful when performing slow eccentric movements when lifting relatively heavy loads as the risk of injury increases.
Here are some examples of the eccentric movement of several exercises:
Brian Danley, CFT
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