title: Metabolic Effects of Glucose-Fructose Co-Ingestion Compared to Glucose Alone during Exercise in Type 1 Diabetes.
abstract: This paper aims to compare the metabolic effects of glucose-fructose co-ingestion (GLUFRU) with glucose alone (GLU) in exercising individuals with type 1 diabetes mellitus. Fifteen male individuals with type 1 diabetes (HbA1c 7.0% ± 0.6% (53 ± 7 mmol/mol)) underwent a 90 min iso-energetic continuous cycling session at 50% VO2maxwhile ingesting combined glucose-fructose (GLUFRU) or glucose alone (GLU) to maintain stable glycaemia without insulin adjustment. GLUFRU and GLU were labelled with13C-fructose and13C-glucose, respectively. Metabolic assessments included measurements of hormones and metabolites, substrate oxidation, and stable isotopes. Exogenous carbohydrate requirements to maintain stable glycaemia were comparable between GLUFRU and GLU (p= 0.46). Fat oxidation was significantly higher (5.2 ± 0.2 vs. 2.6 ± 1.2 mg·kg-1·min-1,p< 0.001) and carbohydrate oxidation lower (18.1 ± 0.8 vs. 24.5 ± 0.8 mg·kg-1·min-1p< 0.001) in GLUFRU compared to GLU, with decreased muscle glycogen oxidation in GLUFRU (10.2 ± 0.9 vs. 17.5 ± 1.0 mg·kg-1·min-1,p< 0.001). Lactate levels were higher (2.2 ± 0.2 vs. 1.8 ± 0.1 mmol/L,p= 0.012) in GLUFRU, with comparable counter-regulatory hormones between GLUFRU and GLU (p> 0.05 for all). Glucose and insulin levels, and total glucose appearance and disappearance were comparable between interventions. Glucose-fructose co-ingestion may have a beneficial impact on fuel metabolism in exercising individuals with type 1 diabetes without insulin adjustment, by increasing fat oxidation whilst sparing glycogen.
authors.affiliation: Department of Diabetes, Endocrinology, Clinical Nutrition and Metabolism, Inselspital, Bern University Hospital, University of Bern, 3010 Bern, Switzerland. lia.bally@insel.ch.
authors.forename: Lia
authors.initials: L
authors.lastname: Bally
authors.affiliation: Department of Diabetes, Endocrinology, Clinical Nutrition and Metabolism, Inselspital, Bern University Hospital, University of Bern, 3010 Bern, Switzerland. patrick.kempf@insel.ch.
authors.forename: Patrick
authors.initials: P
authors.lastname: Kempf
authors.affiliation: Department of Diabetes, Endocrinology, Clinical Nutrition and Metabolism, Inselspital, Bern University Hospital, University of Bern, 3010 Bern, Switzerland. t.zueger@bluewin.ch.
authors.forename: Thomas
authors.initials: T
authors.lastname: Zueger
authors.affiliation: Department of Diabetes, Endocrinology, Clinical Nutrition and Metabolism, Inselspital, Bern University Hospital, University of Bern, 3010 Bern, Switzerland. christian.speck@outlook.com.
authors.forename: Christian
authors.initials: C
authors.lastname: Speck
authors.affiliation: Department of Diabetes, Endocrinology, Clinical Nutrition and Metabolism, Inselspital, Bern University Hospital, University of Bern, 3010 Bern, Switzerland. nicola.pasi@students.unibe.ch.
authors.forename: Nicola
authors.initials: N
authors.lastname: Pasi
authors.affiliation: Department of Radiology, University Hospital Centre and University of Lausanne, 1011 Lausanne, Switzerland. ciller@gmail.com.|Centre for Biomedical Imaging (CIBM), Signal Processing Core, 1015 Lausanne, Switzerland. ciller@gmail.com.
authors.forename: Carlos
authors.initials: C
authors.lastname: Ciller
authors.affiliation: Department of Diabetes, Endocrinology, Clinical Nutrition and Metabolism, Inselspital, Bern University Hospital, University of Bern, 3010 Bern, Switzerland. katrin.feller2@insel.ch.
authors.forename: Katrin
authors.initials: K
authors.lastname: Feller
authors.affiliation: Department of Diabetes, Endocrinology, Clinical Nutrition and Metabolism, Inselspital, Bern University Hospital, University of Bern, 3010 Bern, Switzerland. hannah.loher@bluewin.ch.
authors.forename: Hannah
authors.initials: H
authors.lastname: Loher
authors.affiliation: Department of Physiology, Faculty of Biology and Medicine, University of Lausanne, 1005 Lausanne, Switzerland. robin.Rosset@unil.ch.
authors.forename: Robin
authors.initials: R
authors.lastname: Rosset
authors.affiliation: Department of Cardiology, Interdisciplinary Center for Sports Medicine, Inselspital, Bern University Hospital, University of Bern, 3010 Bern, Switzerland. matthias.wilhelm@insel.ch.
authors.forename: Matthias
authors.initials: M
authors.lastname: Wilhelm
authors.affiliation: Department of Clinical Research and Department of Radiology, University of Bern, 3010 Bern, Switzerland. chris.boesch@insel.ch.
authors.forename: Chris
authors.initials: C
authors.lastname: Boesch
authors.affiliation: Department of Clinical Research and Department of Radiology, University of Bern, 3010 Bern, Switzerland. buehler_tania@gmx.net.
authors.forename: Tania
authors.initials: T
authors.lastname: Buehler
authors.affiliation: Department of Clinical Research and Department of Radiology, University of Bern, 3010 Bern, Switzerland. ayse.dokumaci@insel.ch.
authors.forename: Ayse S
authors.initials: AS
authors.lastname: Dokumaci
authors.affiliation: Department of Physiology, Faculty of Biology and Medicine, University of Lausanne, 1005 Lausanne, Switzerland. luc.tappy@unil.ch.
authors.forename: Luc
authors.initials: L
authors.lastname: Tappy
authors.affiliation: Department of Diabetes, Endocrinology, Clinical Nutrition and Metabolism, Inselspital, Bern University Hospital, University of Bern, 3010 Bern, Switzerland. christoph.stettler@insel.ch.
authors.forename: Christoph
authors.initials: C
authors.lastname: Stettler
mesh_terms: D000328:Adult; D001642:Bicycling; D001786:Blood Glucose / Q000378:metabolism*; D003922:Diabetes Mellitus, Type 1 / Q000378:metabolism*; D004032:Diet; D004040:Dietary Carbohydrates / Q000008:administration & dosage* / Q000097:blood; D004041:Dietary Fats / Q000378:metabolism; D004435:Eating; D015444:Exercise / Q000502:physiology*; D005632:Fructose / Q000008:administration & dosage / Q000378:metabolism / Q000494:pharmacology*; D005947:Glucose / Q000008:administration & dosage / Q000378:metabolism / Q000494:pharmacology*; D006003:Glycogen / Q000378:metabolism; D006728:Hormones / Q000097:blood; D006801:Humans; D007328:Insulin / Q000097:blood; D019344:Lactic Acid / Q000097:blood; D008297:Male; D009132:Muscles / Q000378:metabolism; D010101:Oxygen Consumption; D064133:Sports Nutritional Physiological Phenomena; D055815:Young Adult
chemical_list: D001786:Blood Glucose; D004040:Dietary Carbohydrates; D004041:Dietary Fats; D006728:Hormones; D007328:Insulin; D005632:Fructose; D019344:Lactic Acid; D006003:Glycogen; D005947:Glucose
keywords: carbohydrates; exercise; fructose; glucose; glycaemia; substrate oxidation; type 1 diabetes