Classifying excessive exercise: Examining the relationship between compulsive exercise with obsessive-compulsive disorder symptoms and disordered eating symptoms.

OBJECTIVE: There remains a lack of consensus around nosology for compulsive exercise (CE). Although widely observed in eating disorders (ED), CE shares theoretical overlap with obsessive-compulsive disorder (OCD), where exercise compulsions occur in response to obsessions. Yet, there is limited and mixed evidence of a relationship between CE with OCD. This study aims to explore the appropriate diagnostic classification of CE through examination of CE in relation to OCD, obsessional thinking, and ED symptoms.

METHOD: Two hundred and eighty one adults with mental health symptoms, dieting, and exercise behaviour completed measures of OCD, CE, and disordered eating symptoms. Regression and Receiver Operating Characteristic analyses examined relationships between dimensions of CE with OCD and ED symptoms, and the predictive ability of CE assessment for detecting threshold OCD and ED symptoms.

RESULTS: CE assessment was poor at predicting threshold OCD symptoms, probable Anorexia Nervosa, and Binge Eating Disorder and moderate at detecting probable disordered eating and Bulimia Nervosa. Associations between CE and OCD symptoms were not significant after adjustment for ED symptoms. Obsessional thinking was associated only with lack of exercise enjoyment.

CONCLUSIONS: Results indicate that excessive exercise might represent a distinct disorder, with some shared traits across CE, OCD and ED symptoms. Findings question the utility of adaptation of OCD diagnostic criteria for CE. Assessment and treatment implications are considered.