title: Postexercise nutrient intake timing in humans is critical to recovery of leg glucose and protein homeostasis.
abstract: Although the importance of postexercise nutrient ingestion timing has been investigated for glycogen metabolism, little is known about similar effects for protein dynamics. Each subject (n = 10) was studied twice, with the same oral supplement (10 g protein, 8 g carbohydrate, 3 g fat) being administered either immediately (EARLY) or 3 h (LATE) after 60 min of moderate-intensity exercise. Leg blood flow and circulating concentrations of glucose, amino acids, and insulin were similar for EARLY and LATE. Leg glucose uptake and whole body glucose utilization (D-[6,6-2H(2)]glucose) were stimulated threefold and 44%, respectively, for EARLY vs. LATE. Although essential and nonessential amino acids were taken up by the leg in EARLY, they were released in LATE. Although proteolysis was unaffected, leg (L-[ring-2H(5)]phenylalanine) and whole body (L-[1-13C]leucine) protein synthesis were elevated threefold and 12%, respectively, for EARLY vs. LATE, resulting in a net gain of leg and whole body protein. Therefore, similar to carbohydrate homeostasis, EARLY postexercise ingestion of a nutrient supplement enhances accretion of whole body and leg protein, suggesting a common mechanism of exercise-induced insulin action.
authors.affiliation: Department of Surgery, Vanderbilt University Medical Center, Nashville, Tennessee 37232, USA.
authors.forename: D K
authors.initials: DK
authors.lastname: Levenhagen
authors.forename: J D
authors.initials: JD
authors.lastname: Gresham
authors.forename: M G
authors.initials: MG
authors.lastname: Carlson
authors.forename: D J
authors.initials: DJ
authors.lastname: Maron
authors.forename: M J
authors.initials: MJ
authors.lastname: Borel
authors.forename: P J
authors.initials: PJ
authors.lastname: Flakoll
mesh_terms: D000328:Adult; D000596:Amino Acids / Q000097:blood / Q000493:pharmacokinetics; D001786:Blood Glucose; D004040:Dietary Carbohydrates / Q000493:pharmacokinetics; D004044:Dietary Proteins / Q000493:pharmacokinetics*; D004435:Eating / Q000502:physiology*; D004734:Energy Metabolism / Q000502:physiology; D005260:Female; D005947:Glucose / Q000493:pharmacokinetics*; D005990:Glycerol / Q000097:blood; D006706:Homeostasis / Q000502:physiology*; D006801:Humans; D007328:Insulin / Q000097:blood; D007866:Leg; D008297:Male; D009124:Muscle Proteins / Q000378:metabolism; D018482:Muscle, Skeletal / Q000378:metabolism; D009751:Nutritional Requirements; D005082:Physical Exertion / Q000502:physiology*; D013997:Time Factors
chemical_list: D000596:Amino Acids; D001786:Blood Glucose; D004040:Dietary Carbohydrates; D004044:Dietary Proteins; D007328:Insulin; D009124:Muscle Proteins; D005947:Glucose; D005990:Glycerol