Effects of an Electrolyte Additive on Hydration and Drinking Behavior During Wildfire Suppression

Objective.-The purpose of this study was to compare the effects of a water + electrolyte Solution versus plain water on changes in drinking behaviors. hydration status. and body temperatures during wildfire suppression. Methods.-Eight participants Consumed plain water, and eight participants consumed water Plus ail electrolyte additive during 15 hours of wildfire Suppression. Participants wore a specially outfitted backpack hydration system equipped with a digital flow meter system affixed inline to measure drinking characteristics (drinking frequency and volume). Body weight and urine-specific gravity were collected pre- and postshift. Ambient. core, and skin temperatures were measured continuously using a wireless system. Work Output was monitored using accelerometry. Results.-There were no differences between (groups for body weight, drinking frequency, temperature data, activity, or urine-specific gravity (1.019 +/- 0.007 to 1.023 +/- 0.010 vs. 1.019 +/- 0.005 to 1.024 +/- 0.009 for water and water + electrolyte groups pre- and postshift, respectively P <.05). There was a main effect for time for body weight, demonstrating an overall decrease (78.1 +/- 13.3 work shift. The water group and 77.3 +/- 13.3 kg pre- and postshift. respectively: P <.05) across the consumed more total fluid (main effect for treatment) than the water + electrolyte group (504 +/- 472 vs. 295 +/- 279 mL.h(-1) for the water and water + electrolyte groups. respectively: P <.05). Conclusion.-The addition of an electrolyte mixture to plain water decreased the overall fluid consumption of the water + electrolyte group by 220 mL.h(-1) (3.3 L.d(-1)). Supplementing water with electrolytes can reduce the amount Of fluid necessary to consume and transport during extended activity. This can minimize carrying excessive weight. possibly reducing fatigue during extended exercise.