(P32-027-23) Hydration Practices of Half Marathoners During the Hyannis Half-Marathon 2022

Objectives: Overhydration is a main case of exercise-associated hyponatremia (EAH). Although several studies have assessed hydration practices of marathon runners, only a few have assessed half marathoners. The purpose of this study was to explore the self-reported hydration practices of half marathoners running in the 2022 Hyannis Marathon event. This unique study compared hydration practices in three scenarios, an intended long training run (LTR), an intended half marathon, and the actual half marathon. The researchers hypothesized that volumes and strategies would be different among the scenarios and that drinking to thirst would be limited.

Methods: In a cross-sectional pre- and post-race online survey design, a pre-race survey was administered online (Qualtrics, UT) and sent to all running participants. The link was also posted on the event website page. Forty-two participants completed the pre-race survey. Participants who wished to complete the post-race survey submitted their email on the pre-race survey and 42 completed the post-race survey 2 – 48 hours after the race.

Results: Overall, hydration strategy agreement was moderate (53-63%) when comparing the three scenarios. The runners were selecting the same hydration strategy most of the time. Interestingly, 38% of runners (n=14) selected either drinking according to thirst or ad libitum as their hydration strategy during the event. However, only 14% of those runners carried their own hydration, suggesting that to truly utilize those strategies, a runner would need hydration access real-time. In addition, intended volumes before the half-marathon compared to long training run were moderately correlated (R = 0.69, p = 0.000012).

Conclusions: These results suggest that the runners in this study may not be clear on the appropriate hydration strategies recommend for long distance running. Further education on hydration practices is still recommended for half marathon runners. Practicing recommended hydration practices in both training and a race will optimize performance and health, as well as avoid EAH. Although EAH primarily occurs in endurance and ultra-endurance events and may be sport specific, growing evidence suggests that EAH is also occurring in shorter events.

Funding Sources: None