The Comparison Of Hydration Practices Between Full- And Half-marathoners At The Hyannis Marathon Event

PURPOSE: To assess and compare the self-reported hydration practices in both full- and half-marathon runners comparing 2020 to 2022 from same event. Inconsistent hydration practices may lead to overhydration, a primary cause of exercise-associated hyponatremia (EAH). Drinking according to thirst (DTT) is recommended to prevent EAH in lieu of a personalized hydration plan. METHODS: Cross-sectional survey design. An online survey utilized the Hyannis Marathon registrants during 2020 (full-marathoners, n = 49) and repeated among 2022 (half-marathoners, n = 42). Survey questions addressed hydration practices during an intended long training run (LTR), an intended event, and the actual race. Participants completed a pre- and post-race survey. RESULTS: When comparing actual volumes consumed by the full-marathoners to volumes intended, there was a significant correlation of 0.49 (p = 0.0008, n = 29), vs. a correlation of 0.13 (p = 0.52, n = 25) for the same comparison in half-marathoners. Hydration practices selected included DTT 17% of the time, while half marathoners selected DTT 21% of the time. None of the marathoners and 5% of the half marathoners reported having a personalized hydration plan. The reported hydration information sources (2020) were similar to the half marathoners (2022), including running friends (22% vs. 19%), other Internet sources (22% vs. 19%), and running magazines or books (18% vs. 22%). The comparison of hydration strategies between an intended LTR and an intended event was 69% (2020) and 63% (2022) agreement. When comparing the hydration strategy between an intended event and the actual event, the agreement was 52% (2020) vs. 62% (2022). When comparing the hydration strategy of the intended LTR to the actual event, the agreement was 65% (2020) vs. 53% (2022). CONCLUSION: In this study, both half- and full-marathon runners reported some differences in hydration practices when comparing a LTR, an intended event, and an actual event. If runners mimic appropriate hydration practices during training when running an event, the risk of EAH may be decreased. Improvements in hydration practices of runners from 2020 to 2022 included hydration strategy selection and consistency among scenarios. The primary limitations of this study were the self-reported nature of this data and the small sample size.