To the Editor: Nonsuicidal self-injury refers to deliberate damage to one’s own bodily tissue without suicidal intent. Nonsuicidal self-injury is a pervasive behavior problem, yet effective treatments are lacking. Research has found that people engage in nonsuicidal self-injury for several different reasons, including tension relief and the induction of pleasurable affective states (1). Preliminary evidence suggests that the release of endogenous opioids may be central to this process of emotional regulation (2). We hypothesized that aerobic physical exercise, which has been shown to regulate mood (3) and stimulate the release of beta-endorphin (4), would decrease the frequency of nonsuicidal self-injury. We report on the results of a single-case study demonstrating the effectiveness of physical exercise as a treatment for nonsuicidal self-injury.
“Ms. A” was an overweight 26-year-old woman with a 13-year history of ongoing psychological and pharmacological treatment for persistent nonsuicidal self-injury, including one inpatient hospitalization for nonsuicidal self-injury within the past year. Ms. A was receiving twice-weekly outpatient psychotherapy for the duration of this study. In an initial baseline assessment, she reported 2.25 episodes of nonsuicidal self-injury per week over the previous month, including self-hitting and head-banging.
We provided Ms. A with a 60-minute workout video, instructing her to exercise three times per week and to exercise in response to nonsuicidal self-injury urges at any time. We also provided a daily assessment form in which she recorded mood and self-injurious urges (both on 0–9 scales) and behaviors.
The frequency of Ms. A’s nonsuicidal self-injury decreased immediately after the introduction of exercise to 0.37 times per week during a five-week experimental phase. She then independently discontinued exercise. During this quasi-experimental return to baseline, nonsuicidal self-injury increased to 2.33 times per week. When exercise was re-introduced, nonsuicidal self-injury decreased to 0.00 times per week for the remainder of the study.
Overall, nonsuicidal self-injury frequency was significantly lower during exercise phases (M=0.29, SD=0.49) relative to nonexercise phases ([M=2.20, SD=0.45] t=6.93, df=10, p<0.001). Moreover, analysis of mood ratings showed an increase from before exercise (M=2.23, SD=0.86) to after (M=4.77, SD=1.48) exercise (t=7.56, df=50, p<0.001). When Ms. A exercised in direct response to self-injurious thoughts, exercise acutely reduced her urge to self-injure, from before (M=3.00, SD=1.87) to after (M=0.15, SD=0.38) exercise in every single instance (t=5.38, df=24, p<0.001). An 8-week follow-up interview revealed sustained improvement in Ms. A’s mental and physical well-being and a decrease in body weight by 20 pounds.
These initial results are promising, and future research is needed to further investigate the effectiveness of exercise as a treatment for nonsuicidal self-injury.
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2.Roth AS, Ostroff RB, Hoffman RE: Naltrexone as a treatment for repetitive self-injurious behavior: an open-label trial. J Clin Psychiatry 1996; 57:233–237
3.Yeung RR: The acute effects of exercise on mood state. J Psychosom Res 1996; 40:123–141
4.Carr DB, Bullen BA, Skrinar GS, Arnold MA, Rosenblatt M, Beitins IZ, Martin JB, McArthur JW: Physical conditioning facilitates the exercise-induced secretion of beta-endorphin and beta-lipotropin in women. N Engl J Med 1981; 305:560–563