title: Sucrose ingestion after exhaustive exercise accelerates liver, but not muscle glycogen repletion compared with glucose ingestion in trained athletes.
abstract: The purpose of this study was to assess the effects of sucrose vs. glucose ingestion on postexercise liver and muscle glycogen repletion. Fifteen well-trained male cyclists completed two test days. Each test day started with glycogen-depleting exercise, followed by 5 h of recovery, during which subjects ingested 1.5 g·kg(-1)·h(-1) sucrose or glucose. Blood was sampled frequently and (13)C magnetic resonance spectroscopy and imaging were employed 0, 120, and 300 min postexercise to determine liver and muscle glycogen concentrations and liver volume. Results were as follows: Postexercise muscle glycogen concentrations increased significantly from 85 ± 27 (SD) vs. 86 ± 35 mmol/l to 140 ± 23 vs. 136 ± 26 mmol/l following sucrose and glucose ingestion, respectively (no differences between treatments: P = 0.673). Postexercise liver glycogen concentrations increased significantly from 183 ± 47 vs. 167 ± 65 mmol/l to 280 ± 72 vs. 234 ± 81 mmol/l following sucrose and glucose ingestion, respectively (time × treatment, P = 0.051). Liver volume increased significantly over the 300-min period after sucrose ingestion only (time × treatment, P = 0.001). As a result, total liver glycogen content increased during postexercise recovery to a greater extent in the sucrose treatment (from 53.6 ± 16.2 to 86.8 ± 29.0 g) compared with the glucose treatment (49.3 ± 25.5 to 65.7 ± 27.1 g; time × treatment, P < 0.001), equating to a 3.4 g/h (95% confidence interval: 1.6-5.1 g/h) greater repletion rate with sucrose vs. glucose ingestion. In conclusion, sucrose ingestion (1.5 g·kg(-1)·h(-1)) further accelerates postexercise liver, but not muscle glycogen repletion compared with glucose ingestion in trained athletes.
authors.affiliation: NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Centre, Maastricht, The Netherlands; Department of Sport, Exercise, and Rehabilitation, Northumbria University, Newcastle upon Tyne, United Kingdom;
authors.forename: Cas J
authors.initials: CJ
authors.lastname: Fuchs
authors.affiliation: Department for Health, University of Bath, Bath, United Kingdom;
authors.forename: Javier T
authors.initials: JT
authors.lastname: Gonzalez
authors.affiliation: NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Centre, Maastricht, The Netherlands;
authors.forename: Milou
authors.initials: M
authors.lastname: Beelen
authors.affiliation: NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Centre, Maastricht, The Netherlands;
authors.forename: Naomi M
authors.initials: NM
authors.lastname: Cermak
authors.affiliation: Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne, United Kingdom; and Newcastle Magnetic Resonance Centre, Newcastle University, Newcastle upon Tyne, United Kingdom.
authors.forename: Fiona E
authors.initials: FE
authors.lastname: Smith
authors.affiliation: Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne, United Kingdom; and Newcastle Magnetic Resonance Centre, Newcastle University, Newcastle upon Tyne, United Kingdom.
authors.forename: Pete E
authors.initials: PE
authors.lastname: Thelwall
authors.affiliation: Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne, United Kingdom; and Newcastle Magnetic Resonance Centre, Newcastle University, Newcastle upon Tyne, United Kingdom.
authors.forename: Roy
authors.initials: R
authors.lastname: Taylor
authors.affiliation: Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne, United Kingdom; and.
authors.forename: Michael I
authors.initials: MI
authors.lastname: Trenell
authors.affiliation: Department of Sport, Exercise, and Rehabilitation, Northumbria University, Newcastle upon Tyne, United Kingdom; Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne, United Kingdom; and.
authors.forename: Emma J
authors.initials: EJ
authors.lastname: Stevenson
authors.affiliation: NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Centre, Maastricht, The Netherlands; l.vanloon@maastrichtuniversity.nl.
authors.forename: Luc J C
authors.initials: LJ
authors.lastname: van Loon
mesh_terms: D056352:Athletes; D001642:Bicycling / Q000502:physiology; D004040:Dietary Carbohydrates / Q000378:metabolism; D004435:Eating / Q000502:physiology*; D015444:Exercise / Q000502:physiology*; D005947:Glucose / Q000008:administration & dosage*; D006003:Glycogen / Q000378:metabolism*; D006801:Humans; D008099:Liver / Q000378:metabolism*; D008297:Male; D018482:Muscle, Skeletal / Q000378:metabolism*; D010807:Physical Endurance / Q000502:physiology; D013395:Sucrose / Q000008:administration & dosage*
chemical_list: D004040:Dietary Carbohydrates; D013395:Sucrose; D006003:Glycogen; D005947:Glucose
keywords: 13C magnetic resonance spectroscopy; carbohydrate; endurance exercise; fructose; recovery