Background and aims: In nomothetic research exercise addiction is studied on the basis of symptoms which are most often linked to exercise volume. However, other factors may also affect individuals' susceptibility to the disorder. The aim of this research was to examine the influence of gender, social context (team or individual sport), and level of athletic training on symptoms of exercise addiction. Methods: Two groups of university athletes – sport- ( n = 57) and non-sport orientation ( n = 90) – and a group of elite ultra-marathon runners ( n = 95) completed the Exercise Addiction Inventory (EAI). The psychometric properties of the Spanish EAI were determined. Results: EAI scores were higher in men than women ( p = .018). Participants in team sports reported higher EAI scores than individual athletes ( p = .005). Elite runners scored higher on the EAI than university athletes ( p = .005), but their scores were unrelated to the volume of training. The prevalence of “at risk” for exercise addiction was 7%–10% in university athletes and 17% among the ultra-marathon runners. The Spanish EAI showed good psychometric properties. Discussion: The results of the current inquiry show that several factors – including gender, level of athletic training, and social context of the training – affect exercise addiction and, in line with the literature, the volume of exercise did not emerge as an index of susceptibility to exercise addiction.