Dk. Levenhagen et al., Postexercise nutrient intake timing in humans is critical to recovery of leg glucose and protein homeostasis, AM J P-ENDO, 280(6), 2001, pp. E982-E993
Citations number
48
Categorie Soggetti
Endocrinology, Nutrition & Metabolism
Journal title
AMERICAN JOURNAL OF PHYSIOLOGY-ENDOCRINOLOGY AND METABOLISM
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 sa
me oral supplement (10 g protein, 8 g carbohydrate, 3 g fat) being administ
ered either immediately (EARLY) or 3 h (LATE) after 60 min of moderate-inte
nsity exercise. Leg blood flow and circulating concentrations of glucose, a
mino acids, and insulin were similar for EARLY and LATE. Leg glucose uptake
and whole body glucose utilization (D-[6,6-H-2(2)]glucose) were stimulated
threefold and 44%, respectively, for EARLY vs. LATE. Although essential an
d nonessential amino acids were taken up by the leg in EARLY, they were rel
eased in LATE. Although proteolysis was unaffected, leg (L-[ring-H-2(5)] ph
enylalanine) and whole body (L-[1-C-13]leucine) protein synthesis were elev
ated threefold and 12%, respectively, for EARLY vs. LATE, resulting in a ne
t gain of leg and whole body protein. Therefore, similar to carbohydrate ho
meostasis, EARLY postexercise ingestion of a nutrient supplement enhances a
ccretion of whole body and leg protein, suggesting a common mechanism of ex
ercise-induced insulin action.