Effects of Caffeine on Muscle Glycogen Utilization and the Neuroendocrine Axis during Exercise1
Laurent D, Schneider K, Prusaczyk W, Franklin C, Vogel S, Krssak M, Petersen K, Goforth H, Shulman G. Effects of Caffeine on Muscle Glycogen Utilization and the Neuroendocrine Axis during Exercise1. The Journal Of Clinical Endocrinology & Metabolism 2000, 85: 2170-2175. PMID: 10852448, DOI: 10.1210/jcem.85.6.6655.Peer-Reviewed Original ResearchConceptsMuscle glycogen contentMuscle glycogen utilizationGlycogen contentCaffeine ingestionNeuroendocrine axisGlycogen utilizationGlycogen-sparing effectFree fatty acid concentrationsBeta-endorphin levelsCaffeine-treated groupExercise-induced glycogen depletionMaximal oxygen consumptionEffects of caffeineHigher muscle glycogen contentPlacebo groupExercise enduranceFatty acid concentrationsPlasma concentrationsNeuroendocrine hormonesCortisol releaseProlonged exerciseGlycogen depletionPlasma lactateNormal valuesThigh musclesIntramuscular Glycogen and Intramyocellular Lipid Utilization during Prolonged Exercise and Recovery in Man: A 13C and 1H Nuclear Magnetic Resonance Spectroscopy Study1
Krssak M, Petersen K, Bergeron R, Price T, Laurent D, Rothman D, Roden M, Shulman G. Intramuscular Glycogen and Intramyocellular Lipid Utilization during Prolonged Exercise and Recovery in Man: A 13C and 1H Nuclear Magnetic Resonance Spectroscopy Study1. The Journal Of Clinical Endocrinology & Metabolism 2000, 85: 748-754. PMID: 10690886, DOI: 10.1210/jcem.85.2.6354.Peer-Reviewed Original ResearchProlonged exerciseIMCL contentGlycogen contentBaseline valuesSoleus muscleMuscle glycogenMuscle groupsGreater muscle glycogen utilizationForearm musclesGlycogen concentrationLipid utilizationIntramyocellular lipid poolMuscle glycogen utilizationCalf muscle groupThigh muscle groupsIntramyocellular glycogenNonexercising muscleIntramuscular glycogenGlycogen depletionGlycogen utilizationTime of exhaustionLeg musclesThigh musclesSubmaximal intensitiesMuscle