Review article
Motor activity phenomenon in anorexia nervosa – biological aspects

Increased motor activity is a commonly described symptom in the course of anorexia nervosa. Dietary restrictions and intense physical exercise lead to reduction of body mass in the process of accelerating caloric consumption. Additionally a permanent increase of motor activity which is observed in some female patients is often not perceived by the patients. This feature is considered to be different from exercise. Assessment of physical activity in anorexia nervosa patients is extremely difficult. All attempts at estimating time spent on physical exercise seem to be unreliable. There is not much information about the significance of this symptom and about the lack of it. The research undertaken so far has not established unambiguous connections of motor activity to osteoporosis risk.
Objective: To review the literature concerning the hyperactivity phenomenon in anorexia nervosa patients.
Material and method: Articles from the Medline database were analyzed using the key words: anorexia nervosa, hyperactivity, motor activity.
Results: Neuropsychological aspects and the hyperactivity phenomenon in animal models of anorexia nervosa were reviewed. The authors used various methods to assess motor activity. Neurobiological concepts try to explain hyperactivity in terms of HPA dysregulation and the influence of orexin and leptin imbalance, based mainly on studies in rats – the activity-based anorexia model.