In . In general, tendon strengthening is tied directly to muscle strenght and joint stabilization exercises. Recent research and opinion suggests that eccentric loads to tendons (muscle-tendon unit is contracting and lengthening at the same time) stimulate tendon cell activity and regeneration. Gym exercises often referred to as "negatives" often place eccentric loads on tendons. Occasionally at partially torn tendon and frequently a completely torn tendon require evaluation by a specialist and potential surgery.