Perda de eletrólitos durante uma competi？？o de duatlo terrestre no calor

prolonged sports events such as duathlon (6 km running, 26 km cycling and 4 km running), may lead the athlete to a fluid and electrolyte imbalance, due to high sweat rates, especially in a hot environment. the present study evaluated sodium (na+), potassium (k+) and chloride (cl-) losses during a duathlon competition performed in the heat (31,2 oc and 51% relative humidity), analyzing the sweat composition and blood levels of these electrolytes. twelve athletes took part in this study. blood samples were obtained pre- and post-exercise and sweat was collected using sweat patches. the average time to complete the competition was 85.0 ± 6.57 min. the percentage of dehydration was 3.0 ± 0.92%. the replacement of fluid losses was 31 ± 18.7%. the sweat rate was 1.86 ± 0.56 l？h-1. sweat na+, k+, and cl-concentrations were 71 ± 26.05 mmol？l-1, 5.43 ±1.98 mmol？l-1 and 58.93 ± 25.99 mmol？l-1, respectively. the total sweat loss of na+, k+ and cl- was 132.11± 62.82 mmol, 10.09 ± 5.01 mmol and 109.75 ± 58.49 mmol, respectively. in conclusion, the athletes did not drink enough liquid to replace their volume of fluid loss. furthermore, the participants presented high sweat rate accompanied by losses of na+, k+ and cl-. however, serum electrolyte concentrations were not changed.