Carbohydrate ingestion does not alter skeletal muscle AMPK signaling during exercise in humans Lee-Young, Robert S., Palmer, Matthew J., Linden, Kelly C., LePlastrier, Kieran, Canny, Benedict J., Hargreaves, Mark, Wadley, Glenn D., Kemp, Bruce E. and McConell, Glenn K. 2006, Carbohydrate ingestion does not alter skeletal muscle AMPK signaling during exercise in humans, American journal of physiology : endocrinology and metabolism, vol. 291, pp. E566-E573, doi: 10.1152/ajpendo.00023.2006. Attached Files Name Description MIMEType Size Downloads Title Carbohydrate ingestion does not alter skeletal muscle AMPK signaling during exercise in humans Author(s) Lee-Young, Robert S. Palmer, Matthew J. Linden, Kelly C. LePlastrier, Kieran Canny, Benedict J. Hargreaves, Mark Wadley, Glenn D. orcid.org/0000-0002-6617-4359 Kemp, Bruce E. McConell, Glenn K. Journal name American journal of physiology : endocrinology and metabolism Volume number 291 Start page E566 End page E573 Publisher American Physiological Society Place of publication Bethesda, Md. Publication date 2006-05-02 ISSN 0193-1849 1522-1555 Keyword(s) adenosine monophosphate-activated protein kinase acetyl-coenzyme A carboxylase contraction glucose uptake metabolism Summary There is evidence that increasing carbohydrate (CHO) availability during exercise by raising preexercise muscle glycogen levels attenuates the activation of AMPK{alpha}2 during exercise in humans. Similarly, increasing glucose levels decreases AMPK{alpha}2 activity in rat skeletal muscle in vitro. We examined the effect of CHO ingestion on skeletal muscle AMPK signaling during exercise in nine active male subjects who completed two 120-min bouts of cycling exercise at 65 ± 1% VO2 peak. In a randomized, counterbalanced order, subjects ingested either an 8% CHO solution or a placebo solution during exercise. Compared with the placebo trial, CHO ingestion significantly (P < 0.05) increased plasma glucose levels and tracer-determined glucose disappearance. Exercise-induced increases in muscle-calculated free AMP (17.7- vs. 11.8-fold), muscle lactate (3.3- vs. 1.8-fold), and plasma epinephrine were reduced by CHO ingestion. However, the exercise-induced increases in skeletal muscle AMPK{alpha}2 activity, AMPK{alpha}2 Thr172 phosphorylation and acetyl-CoA Ser222 phosphorylation, were essentially identical in the two trials. These findings indicate that AMPK activation in skeletal muscle during exercise in humans is not sensitive to changes in plasma glucose levels in the normal range. Furthermore, the rise in plasma epinephrine levels in response to exercise was greatly suppressed by CHO ingestion without altering AMPK signaling, raising the possibility that epinephrine does not directly control AMPK activity during muscle contraction under these conditions in vivo. Language eng DOI 10.1152/ajpendo.00023.2006 Field of Research 110102 Medical Biochemistry: Carbohydrates Socio Economic Objective 970111 Expanding Knowledge in the Medical and Health Sciences HERDC Research category C1.1 Refereed article in a scholarly journal ERA Research output type C Journal article Copyright notice ©2006, American Physiological Society Persistent URL http://hdl.handle.net/10536/DRO/DU:30019465 Document type: Journal Article Collections: Faculty of Health School of Exercise and Nutrition Sciences Institute for Physical Activity and Nutrition Related Links Link Description Connect to published version (restricted access) Go to link with your DU access privileges     Unless expressly stated otherwise, the copyright for items in DRO is owned by the author, with all rights reserved. Versions Version Filter Type Tue, 15 Sep 2009, 12:33:04 EST Tue, 15 Sep 2009, 12:47:39 EST Tue, 15 Sep 2009, 12:48:30 EST Tue, 15 Sep 2009, 14:38:49 EST Tue, 15 Sep 2009, 15:35:52 EST Tue, 15 Sep 2009, 15:37:05 EST Tue, 15 Sep 2009, 15:38:08 EST Fri, 02 Oct 2009, 11:28:18 EST Fri, 27 Nov 2009, 16:08:42 EST Fri, 03 Feb 2012, 13:02:00 EST Tue, 12 Nov 2013, 11:24:27 EST Mon, 16 Jun 2014, 12:50:23 EST Wed, 27 Aug 2014, 22:03:40 EST Filtered Full Citation counts:   Cited 31 times in TR Web of Science Cited 31 times in Scopus Search Google Scholar Access Statistics: 1092 Abstract Views, 0 File Downloads  -  Detailed Statistics Created: Tue, 15 Sep 2009, 12:33:03 EST