Title: Fiber type-specific muscle glycogen sparing due to carbohydrate intake before and during exercise
Authors: De Bock, Katrien ×
Derave, W
Ramaekers, M
Richter, E A
Hespel, Peter #
Issue Date: Jan-2007
Series Title: Journal of applied physiology (Bethesda, Md. : 1985) vol:102 issue:1 pages:183-188
Abstract: The effect of carbohydrate intake before and during exercise on muscle glycogen content was investigated. According to a randomized crossover study design, eight young healthy volunteers (n = 8) participated in two experimental sessions with an interval of 3 wk. In each session subjects performed 2 h of constant-load bicycle exercise ( approximately 75% maximal oxygen uptake). On one occasion (CHO), they received carbohydrates before ( approximately 150 g) and during (1 body weight(-1).h(-1)) exercise. On the other occasion they exercised after an overnight fast (F). Fiber type-specific relative glycogen content was determined by periodic acid Schiff staining combined with immunofluorescence in needle biopsies from the vastus lateralis muscle before and immediately after exercise. Preexercise glycogen content was higher in type IIa fibers [9.1 +/- 1 x 10(-2) optical density (OD)/mum(2)] than in type I fibers (8.0 +/- 1 x 10(-2) OD/mum(2); P < 0.0001). Type IIa fiber glycogen content decreased during F from 9.6 +/- 1 x 10(-2) OD/mum(2) to 4.5 +/- 1 x 10(-2) OD/mum(2) (P = 0.001), but it did not significantly change during CHO (P = 0.29). Conversely, in type I fibers during CHO and F the exercise bout decreased glycogen content to the same degree. We conclude that the combination of carbohydrate intake both before and during moderate- to high-intensity endurance exercise results in glycogen sparing in type IIa muscle fibers.
ISSN: 8750-7587
Publication status: published
KU Leuven publication type: IT
Appears in Collections:Department of Kinesiology - miscellaneous
Exercise Physiology Research Group
Laboratory of Angiogenesis and Vascular Metabolism (Vesalius Research Center) (+)
× corresponding author
# (joint) last author

Files in This Item:
File Status SizeFormat
D60B85A2-AABA-41D0-A0F9-ADE20FB9A059.metapaper Published 4KbUnknownView/Open


All items in Lirias are protected by copyright, with all rights reserved.

© Web of science