Reoccurrence of adverse medical incidents in repeat ultraendurance triathlon competitors.

Background: Ironman-distance events are ultra-endurance competitions involving three sports, leading to various adverse medical incidents. While some athletes compete in the same event over multiple years, medical trends among repeat competitors have not been studied. This study aimed to determine the recurrence of common medical incidents in repeat competitors over time in a longstanding Ironman-distance championship event.

Methods: Data were collected using standardized sheets completed by nurses and physicians during athlete medical evaluations from 1989-2019. Competitors (N.=427) were included in the analysis if they received medical evaluation in at least three competitions within a fifteen-year period. Bivariate correlations were calculated to determine associations among medical incidents during competitors' first year of medical evaluation. Logistic regression analyses were performed to investigate the likelihood of medical incidents reoccurring in subsequent years following the initial occurrence.

Results: Significant associations were found between several adverse medical incidents during competitors' first medical evaluations and for those evaluated in 3+ years. Competitors diagnosed with hyponatremia (aOR=2.42, 95% CI: 1.07-5.46), nausea (aOR=1.83, 95% CI: 1.14-2.94), dizziness (aOR=1.71, 95% CI: 1.09-2.68), and muscle cramps (aOR=1.62, 95% CI: 1.05-2.50) during their first year were significantly more likely to return with the same issue in subsequent years. In contrast, those who experienced vomiting during their first year were less likely to return for the same problem (aOR=0.45, 95% CI: 0.27-0.77).

Conclusions: There are significant correlations and clear patterns of recurrence for specific medical incidents among elite ultra-endurance triathletes. Further analyses of other triathlon repeat populations and more specific examinations by age and sex are needed.