INTRODUCTION:Regular physical exercise has numerous benefits. However, there is a subset of the exercising population who may develop a compulsion to exercise excessively and who may, as a consequence, display physiological and psychological changes that have a direct influence on their quality of life.OBJECTIVE:Our objective was to determine if there are differences between male and female athletes' scores on measures of negative addiction symptoms, quality of life, mood and sleep. Methods: 144 female and 156 male athletes participated in this study by answering the following questionnaires: Negative Addiction Scale, Beck Depression Inventory, Trait Anxiety Inventory, Profile of Mood States, SF-36 Quality of Life, Pittsburgh Sleep Quality and Epworth Sleepiness Scale.RESULTS:Higher dedication to training sessions in the male group, and members of the female group with symptoms of negative addiction to exercise showed a lower score on vigor observed by the Profile of Mood States compared to the males in both situations. We also observed depression symptoms in both members of groups who had negative addiction symptoms when compared with their peers without symptoms, and these figures were even higher in females compared with the male group in the same situation.CONCLUSION:No differences were seen in the development of negative addiction exercise symptoms in males and females and there were no changes in the quality of life and mood of these athletes. Further studies of eating disorders associated with changes in body image perception could contribute to a better understanding of negative addiction to exercise.