Features associated with excessive exercise in women with eating disorders.

Objective: Excessive exercise and motor restlessness are observed in a substantial number of patients with eating disorders. This trait has been studied extensively among animal models of activity anorexia nervosa (AN) and may hold particular interest as an endophenotype for AN. We explored features associated with excessive exercise across subtypes of eating disorders.

Method: Participants were female probands and affected female relatives from the multi-site international Price Foundation Genetic Studies with diagnoses of AN, bulimia nervosa (BN), and both AN and BN or eating disorder not otherwise specified (ED-NOS) (N=1,857). Excessive exercise was defined based on responses to the Structured Interview for Anorexic and Bulimic Disorders (SIAB).

Results: Among the eating disorder diagnostic groups, excessive exercise was most common among the purging subtype of AN. Individuals who reported excessive exercise also reported lower minimum BMI, younger age at interview, higher scores on anxiety, perfectionism, and eating disorder symptom measures, more obsessions and compulsions, and greater persistence.

Conclusion: Excessive exercise may be associated particularly with the purging subtype of AN as well as with a constellation of anxious/obsessional temperament and personality characteristics among women with eating disorders.