Adrenaline increases skeletal muscle glycogenolysis, pyruvate dehydrogenase activation and carbohydrate oxidation during moderate exercise in humans

Abstract

1. To evaluate the role of adrenaline in regulating carbohydrate metabolism during moderate exercise, 10 moderately trained men completed two 20 min exercise bouts at 58 ± 2% peak pulmonary oxygen uptake (VO2,peak). On one occasion saline was infused (CON), and on the other adrenaline was infused intravenously for 5 min prior to and throughout exercise (ADR). Glucose kinetics were measured by a primed, continuous infusion of 6,6-[2H]glucose and muscle samples were obtained prior to and at 1 and 20 min of exercise. 2. The infusion of adrenaline elevated (P < 0.01) plasma adrenaline concentrations at rest (pre-infusion, 0.28 ± 0.09; post-infusion, 1.70 ± 0.45 nmol l-1; means ± S.E.M.) and this..