Assessing Hydration Knowledge And Its Effects On Soldier Performance

Hydration is often neglected in military routines working under extreme conditions and can impact physical and mental performance. Symptoms such as early fatigue, cramps, and lack of concentration directly affecting performance and clinical safety. PURPOSE: To assess the association of knowledge and hydration status of Brazilian Army soldiers. METHODS: Cross-sectional descriptive study of 20 male soldiers were assessed using a validated questionnaire (Bouzas Marins, 2017) to evaluate hydration knowledge and practices, additionally to hydration status by saliva sample (MX3 diagnostics®) and body composition by bioimpedance (InBody 270®). Descriptive statistics and chi-square test (χ2) was applied with a significance level of p ≤ 0.05. RESULTS: Soldiers aged 18.75 ± 1.21 yrs., height 1.75 ± 0.06 m, body mass 65.33 ± 5.44 kg, total body water 41.98 ± 3.39 L, hydration status 75.95 ± 18.44 (mOsm). Although most soldiers recognize the importance of hydration, there are gaps in understanding recommended practices, such as the use of isotonic drinks and monitoring fluid loss. Only a small portion reported seeking specialized hydration guidance. Regarding when to drink fluids, 90% of respondents chose "before feeling thirsty" regardless of the season. Only one soldier indicated regularly weighing before and after training sessions. More than 60% of the soldiers were dehydrated at the time of the interview (hydration status >65 mOsm). No significant association was observed between the hydration category and daily water intake (χ2 = 11.838, p = 0.159), hydration habits during training (χ2 = 8.141, p = 0.228), use of isotonic drinks (χ2 = 13.217, p = 0.105), and type of liquid solution (χ2 = 9.586, p = 0.792). However, there was a significant association between dehydration symptoms previously experienced by military personnel and hydration levels (χ2 = 29.44, p = 0.009). CONCLUSIONS: Brazilian Army soldiers recognize the importance of hydration, but there are practical knowledge gaps, especially in using isotonic drinks and monitoring fluid loss. Most were dehydrated during the assessment, with dehydration significantly linked to previous symptoms. Enhanced hydration education, including fluid balance monitoring should be emphasize and could improve their performance and safety in heat stress. Supported by: Supported by Pró-Pesquisa CADESM/DECEx/Brazilian Army, LIQUIDZ® and MX3 Diagnostics®.