Exercise dependence in relation to competitive orientation of runners.

An increasing number of runners seem to be vulnerable to the exercise dependence (ED) syndrome, a clinical disorder in which the athlete is unwilling to alter or discontinue training regimens despite medical contraindications to continued training compliance. As habituation to a stimulus has been regarded to be a diagnostic criterion of an addicted state, we hypothesized that performance in running events of increasing distances would be accompanied by an increased tendency towards ED. To examine this relationship, an exercise addiction scale was completed by recreational (non-competitive) runners (N = 33), five kilometer (5K) runners (N = 24), marathoners (N = 32), and ultramarathon (50 miles) runners (N = 61). ANOVA procedures indicated that both marathoners and ultramarathoners showed significantly higher ED scores [3.78 +/- 1.6 (SD) and 4.59 +/- 1.8, respectively] as compared to 5K (2.9 +/- 1.0) and recreational runners (2.16 +/- 1.3) (p < 0.05). In addition, ultramarathoners presented significantly higher ED scores than those of marathoners (p < 0.05). The data indicate that a tendency towards ED may motivate participation in competition of increasing distance and support a habituation effect consistent with acquired dependence behavior.