Exercise addiction is widely studied, but an official clinical diagnosis does not exist for this behavioral addiction. Earlier research using various screening instruments examined the absolute scale values while investigating the disorder. The Exercise Addiction Inventory-3 (EAI-3) was recently developed with two subscales, one denoting health-relevant exercise and the other addictive tendencies. The latter has different cutoff values for leisure exercisers and elite athletes. Therefore, the present 15-country study (n = 3,760) used the EAI-3 to classify the risk of exercise addiction (REA), but only if the participant reported having had a negative exercise-related experience. Based on this classification, the prevalence of REA was 9.5% in the sample. No sex differences, and few cross-national differences were found. However, collectivist countries reported greater REA in various exercise contexts than individualist countries. Moreover, the REA among athletes was (i) twice as high as leisure exercisers, (ii) higher in organized than self-planned exercises, irrespective of athletic status, and (iii) higher among those who exercised for skill/mastery reasons than for health and social reasons, again irrespective of athletic status. Eating disorders were more frequent among REA-affected individuals than in the rest of the sample. These results do not align with recent theoretical arguments claiming that exercise addiction is unlikely to be fostered in organized sports. The present study questions the current research framework for understanding exercise addiction and offers a new alternative to segregate self-harming exercise from passionate overindulgence in athletic life.

The risk of exercise addiction, characterized by an uncontrollable urge to engage in physical activity, poses significant health risks yet lacks clinical diagnostic criteria. The need for its assessment is increasing in research and applied settings. The present study evaluated the psychometric properties and reliability of the Expanded Exercise Addiction Inventory (EAI-3) within a Danish population. The present study involved 392 Danish adults who were all regular exercisers. Participants completed the EAI-3, the Exercise Dependence Scale-Revised (EDS-R), the SCOFF Questionnaire for eating disorders, the Obsessive–Compulsive Inventory-Revised (OCI-R), and the Ten-Item Personality Inventory (TIPI). Confirmatory factor analysis (CFA) and measurement invariance testing were performed to assess the factor structure and reliability of the EAI-3 across biological sex. The results indicated strong reliability and validity for the EAI-3, with good fit indices across models (CFI =.981, RMSEA =.054). The scale scores demonstrated configural, metric, and scalar invariance, indicating consistent performance across male and female exercisers. Reliability analyses yielded high internal consistency (α =.85, ω =.88), and ROC analysis established a cut-off score of 33.5 for potential exercise addiction risk, with high specificity (.856) and sensitivity (.889). Similar good results emerged from the bifactor model, but the original structure was still preferable. The present study supports the EAI-3 as a valid and reliable tool for screening the risk of exercise addiction among Danish adults, facilitating early identification and potential intervention. Further research should focus on longitudinal studies and clinical validations to enhance the understanding and management of exercise addiction.