Hydration status and water sources in 9-10 year soccer players.

Method: 36 male 9-10 years children were invited to participate in this study, and 30 completed a 24 h urine collection. The Free Water Reserve (FWR) was used to assess the hydration status; additionally, a food record corresponding to the day of urine collection and a lifestyle, and socio-demographic questionnaire was filled with parents help. Anthropometric data were obtained. Food and beverage groups were created and models of unconditional logistic regression were fitted in order to estimate the magnitude of the association between the contribution of food’s water content and the hydration status.