Holtzhausen, L. J.Coetzee, F. F.Vermeulen, Petrus Van der Walt2016-01-082016-01-082013-012013-012013-01http://hdl.handle.net/11660/2089English: Objectives: The aim of this study was to determine the dehydration status of u/19 School rugby players during a game of rugby in the Hopetown district in high temperatures. Methods: This study was a cohort-analytical study on certain variables associated with hydration levels of u/19 rugby players from Hopetown High School during two matches in 2007 and two matches in 2009. The group of rugby players was subjected to a pre- evaluation (15min before the game) followed by a re-evaluation performed 10min after the game. In this way the dehydration status of the players could be determined. Thirty-one rugby players participated. Readings were taken of Urine-Specific Gravity (SG), blood haematocrit, and body mass of every rugby player before and after every rugby match. The student t-test was used to test for significant differences within the group. A significance level of 0.05 was used throughout the study. Results: The anthropometric characteristics in our study for 2007 and 2009 are very similar as expected, and showed a mean length of 177 ± 7-8 cm, ranging from 165 to 190 cm, a mean body mass of 71.5 ± 13.7kg and a mean body mass index (BMI) of 22.88 ± 3.98kg/m2. Between 3 (17%) and 10 (67%) of the players were dehydrated post-match according to the decrease in body mass. The pre-exercise urine specific gravity measures were significantly lower (p < 0.05) before all 4 matches than after the matches as expected, and most of the players could have been better hydrated at the beginning of the match. 20% - 94% of the players were dehydrated pre-match and almost all the players (93% and 100%) were dehydrated after the match. The pre-match mean haematocrit (HCT) and the post-match mean HCT was in the range of 0.46 - 0.47. However, in two of the matches significant differences (p < 0.05) in HCT were recorded. Conclusions: It was alarming to find that a large number of the players were dehydrated before the match, but more important, almost all of them after the match. Recommendations for fluid and electrolyte replacement must be carefully considered and monitored in rugby players to promote safe hydration and avoid hyponatremia.enDissertation (M.Sports. Med. (Sports Medicine))--University of the Free State, 2013Rugby footballRugby football playersDehydration (Physiology)Heat exhaustionUrine-Specific Gravity (SG)Blood haematocrit (%)Youth RugbyDissertationUniversity of the Free State