Heileson, JL, Peterson, M, Adair, KE, and Funderburk, LK. Comparison of a sucrose-based and rice-based sports beverage on hydration status during a 19.3-km foot march in ROTC cadets. J Strength Cond Res 36(4): 1105-1110, 2022-The purpose of this field study was to determine whether a rice-based sport beverage (RB) maintains hydration status compared to a sucrose-based sports beverage (SB) during a load-bearing 19.3-km foot march. Eighteen Reserve Officer Training Corps (ROTC) cadets (male, n = 11; female, n = 7) were randomly assigned to consume either 2.84 L of an RB (carbohydrate, 114 g; sodium, 1306 mg) or SB (carbohydrate, 170 g; sodium, 1136 mg) throughout the duration of the foot march (temperature 14.44° C, humidity 50%). The sports beverages were distributed once before the event and then every 3.2 km for a total of 6 servings (0.47 L each). Pre- and post-urine specific gravity (USG) and body mass were used to assess hydration status. A survey was used to determine subjective ratings of perceived exertion and gastrointestinal (GI) discomfort. The level of significance was set at p < 0.05 for all analyses. Sixteen cadets completed the study. Based on USG, both beverages significantly improved hydration status (USG = 1.017 ± 0.010 pre-march vs. 1.011 ± 0.008 post-march, p = 0.04); however, there was no difference between groups (change in USG = -0.009 ± 0.012 for RB group vs. -0.003 ± 0.008 for SB group, p = 0.92). Ratings for perceived exertion and GI discomfort scores were similar between groups. In conclusion, the RB was as effective as the SB at maintaining hydration status and could potentially reduce GI discomfort. Athletes and military personnel concerned with ensuring appropriate hydration during moderate-intensity endurance events can achieve similar fluid balance from a rice-based sports beverage that is lower in calories, carbohydrate, and sugar.