RESUMEN
BACKGROUND: The aim of this study was to verify the agreement of urine, body mass variations and plasma parameters to determine the hydration status of 14 male runners (29±4 years and 54.3±5.5 mLO2/kg/min) in an official 21.1 km road race. METHODS: The mean dry-bulb temperature and air relative humidity during the road race were 25.1±2.1 °C and 54.7±2.2%, respectively. The volume of water ingested by the runners was monitored using marked volumetric plastic bottles provided at the hydration stations located at 0, 2.5, 5.0, 7.5, 10.5, 14.0, 16.0 and 18.5 km from the starting line. Hydration status was assessed using urine specific gravity (USG), urine osmolality (UOSM) and plasma osmolality (POSM). Furthermore, body mass variation (∆BM) was assessed by comparing body mass (BM) immediately prior and after the race. Total sweat was estimated by ∆BM, added water volume ingested and deducted blood volume collected. The sweat rate was calculated through total sweat and total exercise time. RESULTS: The mean water intake was 0.82±0.40 L, and the mean sweat rate and total sweating were 1440.11±182.13 mL/h and 2.67±0.23 L. After the race, the BM reduced by 1.7±0.4 kg. The ∆BM was -2.41±0.47%, and the plasma volume variation was -9.79±4.6% between pre- and post-running measurements. Despite the POSM increased post-race compared to pre-race, the UOSM and USG did not change. No significant correlations were found between POSM variation with UOSM variation (r=-0.08; P=0.71), USG variation (r=-0.11; P=0.78) or ∆BM (r=0.09; P=0.77). CONCLUSIONS: In conclusion, this study shows that both ∆BM and ∆POSM indicated a hypohydration state after exercise even though the ∆BM did not correlate significantly with ∆POSM. These results demonstrate that ∆BM is a practical method and can be sufficiently sensitive to evaluate the hydration state, but it should be utilized with caution.
Asunto(s)
Deshidratación/orina , Carrera/fisiología , Adulto , Biomarcadores/sangre , Biomarcadores/orina , Índice de Masa Corporal , Deshidratación/sangre , Ingestión de Líquidos/fisiología , Humanos , Masculino , Concentración Osmolar , Volumen Plasmático/fisiología , Sudoración/fisiología , UrinálisisRESUMEN
The purpose of this study was to assess the intensity of official Futsal matches, expressed in different ways. Fourteen male professional Futsal players from a First Division Brazilian team volunteered to participate in this study. Maximal oxygen uptake (VO(2)max) and the heart hate (HR) and oxygen uptake (VO(2)) correlation were determined for each player. The match intensity was estimated from the players' average HR measured during 13 National Futsal League matches. The HR measurements were obtained while the players were in the court but the values recorded while the players were sitting on the bench were not considered. In addition, these HR values were used to estimate the intensity of the effort expressed as a percentage of the maximal HR (% HRmax), percentage of VO(2)max (% VO(2)max), kilocalories per minute (kcal·min(-1)), and total caloric expenditure. The mean intensity of the matches was 86.4 ± 3.8% HRmax, 79.2 ± 9.0% VO(2)max, 18.0 ± 2.2 kcal·min(-1), and 313 ± 9.3 kcal. It was concluded that official Futsal matches have high intensity when expressed in the different ways used in this study. The information provided by this research can be used for planning the athletes' workouts, diets, and resting periods.