title: Glycogen replenishment and repeated maximal effort exercise: effect of liquid carbohydrate.
abstract: We investigated the effects of carbohydrate ingestion on glycogen replenishment and subsequent short duration, high intensity exercise performance. During Session 1, aerobic power was determined and each subject (N = 6) was familiarized with the 100-kJ cycling test (100KJ-Test). During the treatment sessions, the subjects performed a 100KJ-Test (Ride-1), then consumed 0.7 g.kg body mass-1 of maltodextrin (CHO) or placebo (PLC), rested 60 min, and then performed a second 100KJ-Test (Ride-2). Muscle tissue was collected before (Pre-1) and after Ride-1 (Post-1), and before (Pre-2) and after Ride-2 (Post-2), and analyzed for glycogen concentration. Both treatments yielded a significant increase in glycogen levels following the 60-min recovery, but there was no difference between treatments. Time to complete the 100KJ-Test increased significantly for PLC, but not for CHO. These data indicate that the decrease in performance during Ride-2 in PLC was not the result of a difference in glycogen concentration.
authors.affiliation: Dept. of Health, Sport, and Exercise Sciences, University of Kansas, USA.
authors.forename: M D
authors.initials: MD
authors.lastname: Haub
authors.forename: J A
authors.initials: JA
authors.lastname: Potteiger
authors.forename: D J
authors.initials: DJ
authors.lastname: Jacobsen
authors.forename: K L
authors.initials: KL
authors.lastname: Nau
authors.forename: L A
authors.initials: LA
authors.lastname: Magee
authors.forename: M J
authors.initials: MJ
authors.lastname: Comeau
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D001628:Beverages; D001642:Bicycling; D001786:Blood Glucose / Q000378:metabolism; D004040:Dietary Carbohydrates / Q000494:pharmacology*; D004311:Double-Blind Method; D015444:Exercise; D006003:Glycogen / Q000378:metabolism*; D006801:Humans; D019344:Lactic Acid / Q000097:blood; D008297:Male; D018482:Muscle, Skeletal / Q000187:drug effects* / Q000378:metabolism; D011134:Polysaccharides / Q000494:pharmacology*
chemical_list: D001786:Blood Glucose; D004040:Dietary Carbohydrates; D011134:Polysaccharides; D019344:Lactic Acid; C008315:maltodextrin; D006003:Glycogen