Hydration status and sodium concentration in the sweat of adult athletes from the Brazilian Rhythmic Gymnastics Team
Original article - e245648 - Published 20245 Oct 25
DOI:
https://doi.org/10.33233/rbfex.v24i1.5648Keywords:
dehydration, gymnastics, physical exercise, sweat, sodiumAbstract
Introduction: Dehydration in athletes, characterized by a loss of ≥ 2% of body mass during physical exertion, is often correlated with decreased muscle perfusion, increased perceived exertion, impaired muscle hypertrophy, hyperthermia, and reduced cardiac output and thermoregulation. These phenomena culminate in decreased performance and health problems and should be prevented. Objective: To evaluate pre-training hydration status, as well as the impact of a training session on sweat rate, post-training hydration status, and sodium concentration in sweat produced during training of adult athletes from the Brazilian Rhythmic Gymnastics Team. Methods: A cross-sectional study developed with 11 gymnasts, with 10.7 (2.4) years of experience in rhythmic gymnastics (RG) training and 3.4 (2.5) years of participation in the national team. Pre- and post-exercise hydration status was assessed by urine color and density. The dehydration rate was evaluated based on body mass fluctuation between the beginning and end of training, calculated proportionally to initial body weight (%). The sweat rate was calculated based on body mass fluctuation associated with food and beverage intake and urinary excretion during training. The intra- and extra-body water ratio was assessed using bioelectrical impedance analysis. Sweat sodium concentration was measured using the Gx Sweat Patch. Results: The average dehydration rate during training was 0.2%, and 90.9% of the athletes had a dehydration rate below 2%. The average sweat rate was 322.8 ml/hour during training. Urine color and density indicated that 100% of the athletes arrived at training with some degree of hypohydration, with 81.8% mild and 18.2% moderate. At the end of training, 72.7% were moderately dehydrated, and 27.3% were mildly dehydrated. The sweat sodium concentration of all athletes was classified as low. Conclusion: Although fluid replacement during training prevented losses of more than 2% of body mass in most athletes, and sodium concentrations were low in all of them, they were hypohydrated from the beginning of the session and remained so until the end.
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