RESUMEN
PURPOSE: We investigated the effects of caffeine on the ammonia and amino acid metabolism of elite soccer players. METHODS: In this double-blind randomized study, athletes (n = 19) received 5 mg·kg caffeine or lactose (LEx, control) and performed 45 min of intermittent exercise followed by an intermittent recovery test (Yo-Yo IR2) until exhaustion. The caffeine-supplemented athletes were divided into two groups (CEx and SCEx) depending on their serum caffeine levels (<900% and >10,000%, respectively). Data were analyzed by ANOVA and Tukey post hoc test (P < 0.05 was considered to be statistically significant). RESULTS: Caffeine supplementation did not significantly affect the performance (LEx = 12.3 ± 0.3 km·h, 1449 ± 378 m; CEx = 12.2 ± 0.5 km·h, 1540 ± 630 m; SCEx = 12.3 ± 0.5 km·h, 1367 ± 330 m). Exercise changed the blood concentrations of several amino acids and increased the serum concentrations of ammonia, glucose, lactate, and insulin. The LEx group showed an exercise-induced increase in valine (â¼29%), which was inhibited by caffeine. Higher serum caffeine levels abolished the exercise-induced increase (â¼24%-27%) in glutamine but did not affect the exercise-induced increase in alanine (â¼110%-160%) and glutamate (42%-61%). In response to exercise, the SCEx subjects did not exhibit an increase in uremia and showed a significantly lower increase in their serum arginine (15%), citrulline (16%), and ornithine (ND) concentrations. CONCLUSIONS: Our data suggest that caffeine might decrease systemic urea by decreasing the glutamine serum concentration, which decreases the transportation of ammonia to the liver and thus urea synthesis.
Asunto(s)
Aminoácidos/sangre , Atletas , Cafeína/farmacología , Ejercicio Físico/fisiología , Fútbol/fisiología , Uremia/prevención & control , Amoníaco/sangre , Análisis de Varianza , Cafeína/sangre , Método Doble Ciego , HumanosRESUMEN
Epilepsy and other neurological disorders can have profound social, physical and psychological consequences, especially when they begin in childhood. Moreover, seizure episodes may cause fractures, burns, head injuries and oral injuries. This report presents a case history of an adolescent with a severe tongue injury related to epileptic seizures and outlines the proposed treatment, which included use of a maxillary silicone bite guard that allowed healing of the tongue injury within a few months.
Asunto(s)
Mordeduras Humanas/prevención & control , Atención Dental para Enfermos Crónicos , Epilepsia/complicaciones , Ferulas Oclusales , Lengua/lesiones , Adolescente , Anticonvulsivantes/uso terapéutico , Mordeduras Humanas/etiología , Carbamazepina/uso terapéutico , Epilepsia/tratamiento farmacológico , Humanos , MasculinoRESUMEN
OBJECTIVE: To evaluate the effect of caffeine on white cell distribution and muscle injury markers in professional soccer players during exercise. METHODS: 22 male athletes completed a placebo controlled double blind test protocol to simulate a soccer match, followed by a Yo-Yo intermittent recovery test. RESULTS: Exercise caused an increase in packed cell volume that was enhanced by caffeine. Caffeine and exercise had a synergistic effect on the blood lymphocyte count, which increased by about 38% after exercise, and by an additional 35% when combined with caffeine. Caffeine promoted an exercise independent rise in circulating monocytes, and a synergistic action of exercise and caffeine was observed on segmented neutrophils. Caffeine promoted thrombocytosis. Plasma adenosine deaminase, aspartate aminotransferase, and lactate dehydrogenase concentrations were enhanced by exercise, and alanine transaminase concentration was enhanced in both groups, with a synergistic effect of caffeine. CONCLUSIONS: The pronounced increase in the white cell count in the group receiving caffeine appeared to be caused by greater muscle stress and consequently more intense endothelial and muscle cell injury. The use of caffeine may augment the risk of muscle damage in athletes.