Unfortunately I couldn't get it to embed but this video is of Janis Whitlock, director of the Cornell Research Program on Self-Injurious Behavior in Adolescents and Young Adults. In it she outlines the disorder and details its manifestations. http://www.cornell.edu/video/?videoID=204
The case study that my post is in response to can be found at: http://ajp.psychiatryonline.org/cgi/content/full/164/2/350-a
According to this study published in the American Journal of Psychiatry "Non suicidal self-injury refers to deliberate damage to one's own bodily tissue without suicidal intent." During this case study they found a statistical significance between exercise and a reduction in self-injury. In both sources i found references to an opioid-like rush associated with self-injury. However it is also true that similar rushes can be found with exercise. Commonly called "runner's high" many people feel great after they push their bodies past a certain point of exhaustion. While the treatment of Self-Injury is a nobel goal it is concerning to me that the motivation behind the disorder is not being investigated as much as simply channeling the behavior into more socially acceptable venues. In the short term solutions such as exercise may stop the behavior temporarily, but only a change in motivation can alleviate the disorder and stop the behavior completely.