Pre- and Post-Endurance Exercise Gender Differences Between Ultra Marathon Athletes

espanolIntroduccion: La presencia de mujeres en las competencias de ultramaraton se observa cada vez con mas frecuencia. Las adaptaciones fisiologicas y la respuesta al maximo esfuerzo se diferencian influenciados por el sexo. Objetivos: Evaluar las diferencias observadas en los deportistas de ultramaraton o ultratrail (carreras de montana de mas de 42 km) en reposo (adaptaciones fisiologicas) y en el post esfuerzo [fatiga cardiaca inducida por el ejercicio (FCIE)], estratificado por parametros de entrenamiento. Material y metodos: Se reclutaron veinticinco deportistas (mujeres, n=6) que participaron de la carrera cruce Mendoza (55 km en montana) siendo evaluados antes y despues de la finalizacion de la carrera mediante ecocardiografia Doppler y tecnicas de deformacion miocardica (postprocesamiento). Mediante relojes deportivos se documentaron parametros durante el entrenamiento y la carrera. Se realizo extraccion de sangre post esfuerzo inmediato para documentar variables asociadas a fatiga cardiaca. Resultados: Completaron la carrera 24 deportistas, 19 hombres (42±12 anos) y 5 mujeres (38± 4 anos). Las mujeres presentaban parametros similares de entrenamiento y completaron la prueba sin diferencia en tiempos respecto a los hombres. Se observo disminucion de los parametros de funcion miocardica izquierda (FCIE) en el 50% de los hombres y 5 % de las mujeres. Conclusiones: A pesar de no encontrar diferencias en las caracteristicas del entrenamiento, se observo en las mujeres menos adaptacion fisiologica basal y menor incidencia de FCIE. EnglishBackground: The presence of women in ultramarathon competitions has become increasingly frequent. Physiological adaptations and response to maximum exercise are influenced differently according to gender. Objectives: The aim of this study was to evaluate the differences observed in ultramarathon or ultratrail athletes (mountain races over 42 km), at rest (physiological adaptations) and post-endurance exercise [exercise-induced cardiac fatigue (EICF)], stratified by training parameters. Methods: Twenty-five athletes (6 women) who participated in the Mendoza crossing race (55 km in the mountains) were evaluated before and after the end of the race using Doppler echocardiography and myocardial deformation techniques (post-processing). Training and running parameters were documented with sports watches. Immediate post-endurance exercise blood withdrawal was performed to document variables associated with cardiac fatigue. Results: The race was completed by 24 athletes, 19 men (42±12 years) and 5 women (38±4 years). Women and men presented similar training loads and completed the race with no difference in time. Decreased left myocardial function parameters (EICF) were observed in 50% of men and 5% of women. Conclusions: Despite no differences in training characteristics were found, less baseline physiological adaptation and a lower incidence of EICF was observed in women.