Abstract
Background Behavioral addictions often onset in adolescence and increase the risk of psychological and social problems later in life. The core symptoms of addiction are tolerance, withdrawal symptoms, lack of control, and compulsive occupation with the behavior. Psychometrically validated tools are required for detection and early intervention. Adolescent screening instruments exist for several behavioral addictions including gambling and video gaming addiction but not for exercise addiction. Given recent empirical and clinical evidence that a minority of teenagers appear to be experiencing exercise addiction, a psychometrically robust screening instrument is required. Aims The aim of this study was to develop and test the psychometric properties of a youth version of the Exercise Addiction Inventory (EAI) - a robust screening instrument that has been used across different countries and cultures - and to assess the prevalence of exercise addiction and associated disturbed eating. Methods A cross-sectional survey was administered to three high-risk samples (n = 471) aged 11-20 years (mean age: 16.3 years): sport school students, fitness center attendees, and patients with eating disorder diagnoses. A youth version of the EAI (EAI-Y) was developed and distributed. Participants were also screened for disordered eating with the SCOFF Questionnaire. Results Overall, the EAI-Y demonstrated good reliability and construct validity. The prevalence rate of exercise addiction was 4.0% in school athletes, 8.7% in fitness attendees, and 21% in patients with eating disorders. Exercise addiction was associated with feelings of guilt when not exercising, ignoring pain and injury, and higher levels of body dissatisfaction.