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El agotamiento del glucógeno inducido por el ejercicio y la dieta perjudica el rendimiento durante el ejercicio de
Martin Thomassen1, Michael J McKenna2,3,4, Hugo Olmedillas5
1The August Krogh Section for Human Physiology, Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark.
Frontiers in physiology
|September 2, 2025
Resumen
Las reservas bajas de glucógeno muscular afectan significativamente el rendimiento en ejercicios intensos y de corta duración. El agotamiento del glucógeno redujo la capacidad de ejercicio en un 40%, destacando su papel crucial en el rendimiento de alta intensidad.
Área de la Ciencia:
- Fisiología del ejercicio
- Metabolismo muscular
- Ciencias del deporte
Sus antecedentes:
- El glucógeno muscular es una fuente de energía primaria durante el ejercicio de alta intensidad.
- El impacto preciso del agotamiento del glucógeno muscular en el rendimiento del ejercicio intenso de corta duración y la función muscular sigue siendo incompleto.
Objetivo del estudio:
- Investigar el efecto del bajo nivel de glucógeno muscular en el rendimiento de los ejercicios de extensión de rodilla con una sola pierna y en la función contráctil muscular.
- Examinar las alteraciones en la fosforilación de las proteínas reguladoras de Na+/K+-ATPasa (NKA) (AMPK y FXYD1) indicativas de la actividad de la NKA.
Principales métodos:
- Diez hombres sanos se sometieron a pruebas de ejercicio con una pierna agotada de glucógeno y la otra cargada de glucógeno.
- Se realizó un ejercicio intenso de extensión de rodilla con una pierna hasta el fracaso de la tarea.
- La función muscular se evaluó mediante la contracción voluntaria máxima (MVC), las contracciones inducidas eléctricamente y las biopsias musculares.
Principales resultados:
- El tiempo hasta el fracaso de la tarea se redujo en ~ 40% en las piernas agotadas de glucógeno.
- La CVM en reposo y las características contráctiles no se vieron afectadas por los niveles de glucógeno.
- Después del ejercicio, las características de una sola contracción se vieron más deterioradas en las piernas cargadas de glucógeno, mientras que la reducción de MVC fue similar en todas las condiciones.
Conclusiones:
- El bajo contenido de glucógeno muscular afecta significativamente el rendimiento del ejercicio de alta intensidad que dura aproximadamente 5 minutos.
- A pesar de los beneficios potenciales en las características contráctiles, el agotamiento del glucógeno limita la capacidad de ejercicio.
- Los niveles de glucógeno no influyen en la función muscular en reposo.
Palabras clave:
FXYD1 y sus derivadosEl MVCEn el caso de los productos derivados de la biotina, se utilizarán los siguientes métodos:excitabilidadel potasioMás Videos Relacionados
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