Glycogen replenishment and repeated maximal effort exercise: effect of liquid carbohydrate

Int J Sport Nutr. 1999 Dec;9(4):406-15. doi: 10.1123/ijsn.9.4.406.

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.

Publication types

  • Clinical Trial
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Analysis of Variance
  • Beverages
  • Bicycling
  • Blood Glucose / metabolism
  • Dietary Carbohydrates / pharmacology*
  • Double-Blind Method
  • Exercise*
  • Glycogen / metabolism*
  • Humans
  • Lactic Acid / blood
  • Male
  • Muscle, Skeletal / drug effects*
  • Muscle, Skeletal / metabolism
  • Polysaccharides / pharmacology*

Substances

  • Blood Glucose
  • Dietary Carbohydrates
  • Polysaccharides
  • Lactic Acid
  • maltodextrin
  • Glycogen