Resistance training & beta-hydroxy-beta-methylbutyrate supplementation on hormones.

Introduccion:En los ultimos anos hubo un aumento en el interes sobre los efectos de la suplementacion de beta-hidroxi-beta-metilbutirato (HMB) en el musculo esqueletico debido a sus efectos anticatabolicos.Objetivos:Investigar el efecto de la suplementacion de HMB en la composicion corporal, fuerza muscular y hormonas ana-bolicas-catabolicas despues de entrenamiento de resistencia.Metodos:Veinte atletas amateurs del sexo masculino fueron aleatoriamente designados a grupos de suplemento y de control en un diseno cruzado doble ciego, habiendo participado en entrenamiento de resistencia durante cuatro semanas. Antes y despues del periodo de test, fueron obtenidas muestras de sangre en ayunas para determinar las hormonas anabolicas (la hormona del crecimiento y la testosterona) y catabolica (cortisol), habiendo sido medidas la masa adiposa, masa corporal magra (LBM) y fuerza muscular. Los Tests-t dependientes e independientes fueron usados para analizar los datos.Resultados:Des-pues del periodo de entrenamiento, no hubo ninguna diferencia significativa entre los grupos en lo que se refiere a la masa adiposa, LBM y hormonas anabolicas-catabolicas. La suplementacion de HMB resulto en un aumento de fuerza significativamente mayor (p<0,05).Conclusion:El mayor aumento en la fuerza en el grupo HMB no fue acompanado por alteraciones en la composicion corporal y alteraciones hormonales anabolicas-catabolicas ba-sales en la circulacion. Parece que la suplementacion de HMB puede tener efectos beneficos sobre las adaptaciones neurologicas del aumento de fuerza.

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