Related Experiment Video

Updated: Mar 28, 2026

Extracellular Glucose Depletion as an Indirect Measure of Glucose Uptake in Cells and Tissues Ex Vivo

Extracellular Glucose Depletion as an Indirect Measure of Glucose Uptake in Cells and Tissues Ex Vivo

Published on: April 6, 2022

Exercise performed immediately after fructose ingestion enhances fructose oxidation and suppresses fructose storage

Léonie Egli¹, Virgile Lecoultre¹, Jérémy Cros¹

¹Department of Physiology, University of Lausanne, Lausanne, Switzerland;

The American Journal of Clinical Nutrition

|December 25, 2015

Abstract

Background:

Exercise prevents the adverse effects of a high-fructose diet through mechanisms that remain unknown.

Objective:

We assessed the hypothesis that exercise prevents fructose-induced increases in very-low-density lipoprotein (VLDL) triglycerides by decreasing the fructose conversion into glucose and VLDL-triglyceride and fructose carbon storage into hepatic glycogen and lipids.

Design:

Eight healthy men were studied on 3 occasions after 4 d consuming a weight-maintenance, high-fructose diet. On the fifth day, the men ingested an oral (13)C-labeled fructose load (0.75 g/kg), and their total fructose oxidation ((13)CO2 production), fructose storage (fructose ingestion minus (13)C-fructose oxidation), fructose conversion into blood (13)C glucose (gluconeogenesis from fructose), blood VLDL-(13)C palmitate (a marker of hepatic de novo lipogenesis), and lactate concentrations were monitored over 7 postprandial h. On one occasion, participants remained lying down throughout the experiment [fructose treatment alone with no exercise condition (NoEx)], and on the other 2 occasions, they performed a 60-min exercise either 75 min before fructose ingestion [exercise, then fructose condition (ExFru)] or 90 min after fructose ingestion [fructose, then exercise condition (FruEx)].

Results:

Fructose oxidation was significantly (P < 0.001) higher in the FruEx (80% ± 3% of ingested fructose) than in the ExFru (46% ± 1%) and NoEx (49% ± 1%). Consequently, fructose storage was lower in the FruEx than in the other 2 conditions (P < 0.001). Fructose conversion into blood (13)C glucose, VLDL-(13)C palmitate, and postprandial plasma lactate concentrations was not significantly different between conditions.

Conclusions:

Compared with sedentary conditions, exercise performed immediately after fructose ingestion increases fructose oxidation and decreases fructose storage. In contrast, exercise performed before fructose ingestion does not significantly alter fructose oxidation and storage. In both conditions, exercise did not abolish fructose conversion into glucose or its incorporation into VLDL triglycerides. This trial was registered at clinicaltrials.gov as NCT01866215.

Keywords:

de novo lipogenesis energy output fructose gluconeogenesis lactic acid

More Related Videos

Measurement of Fatty Acid β-Oxidation in a Suspension of Freshly Isolated Mouse Hepatocytes

Measurement of Fatty Acid β-Oxidation in a Suspension of Freshly Isolated Mouse Hepatocytes

Published on: September 9, 2021

Simultaneous Detection of c-Fos Activation from Mesolimbic and Mesocortical Dopamine Reward Sites Following Naive Sugar and Fat Ingestion in Rats

Simultaneous Detection of c-Fos Activation from Mesolimbic and Mesocortical Dopamine Reward Sites Following Naive Sugar and Fat Ingestion in Rats

Published on: August 24, 2016

Related Concept Videos

Overview of Carbohydrate Metabolism

Overview of Carbohydrate Metabolism

Carbohydrate metabolism is a fundamental biochemical process that ensures a constant supply of energy to living cells. The most important carbohydrate is glucose, which can be broken down via glycolysis to enter into the Krebs cycle and eventually lead to the production of ATP through oxidative phosphorylation.
Glucose transport into cells is facilitated by a family of transport proteins called GLUT (Glucose Transporters). GLUT4 is the primary glucose transporter for insulin-stimulated glucose...

Glycolysis: Preparatory Phase

Glycolysis: Preparatory Phase

In cellular metabolism (the complete breakdown of glucose to extract energy), glycolysis is the first step. Glycolysis takes place in the cytoplasm of both prokaryotic and eukaryotic cells. Glucose enters heterotrophic cells in two ways. One method is through secondary active transport, where the transport takes place against the glucose concentration gradient. The other mechanism uses a group of integral proteins called GLUT proteins, also known as glucose transporter proteins. These...

Fates of Pyruvate

Fates of Pyruvate

Pyruvate is the end product of glycolysis, where glucose is oxidized to pyruvate, simultaneously reducing NAD+ to NADH. Two molecules of ATP are also produced by substrate-level phosphorylation.
In aerobic organisms, pyruvate is metabolized via the citric acid cycle to produce reduced coenzymes NADH and FADH2. These coenzymes are then oxidized in the electron transport chain to produce ATP and, in the process, regenerate the NAD+ and FAD. As seen in some cell types and organisms, fermentation...

Metabolic States of the Body: The Postabsorptive State

Metabolic States of the Body: The Postabsorptive State

The postabsorptive state usually starts about four hours after a meal and lasts until the next meal is eaten. During this time, the digestive system stops absorbing nutrients, and the body uses stored energy reserves to maintain stable blood glucose levels.
Initially, glycogen stored in the liver is broken down to release glucose into the bloodstream, while glycogen in the muscles is broken down to supply glucose for energy directly within the muscle cells. As glycogen stores diminish,...

Fats as Energy Storage Molecules

Fats as Energy Storage Molecules

Triglycerides are a form of long-term energy storage molecules. They are made of glycerol and three fatty acids. To obtain energy from fat, triglycerides must first be broken down by hydrolysis into their two principal components, fatty acids and glycerol. This process, called lipolysis, takes place in the cytoplasm. The resulting fatty acids are oxidized by β-oxidation into acetyl-CoA, which is used by the Krebs cycle. The glycerol that is released from triglycerides after lipolysis...

Fats as Energy Storage Molecules

Fats as Energy Storage Molecules

Articles linked to this work by shared authors, journal, and citation graph.

Deuterium metabolic imaging reveals greater liver fat contribution from lipogenesis in South Asian men than European men: a potential mechanism underlying elevated type 2 diabetes risk.

Diabetologia·2026

Depot-specific molecular remodelling of human adipose tissue and liver following bariatric surgery revealed by longitudinal multi-omic profiling.

Metabolism: clinical and experimental·2026

Knowledge, perceived harms and reasons for use of disposable electronic cigarettes among youth: a qualitative study in Switzerland.

BMJ public health·2026

Lactose and sucrose each stimulate hepatic de novo lipogenesis: A randomized crossover trial.

The American journal of clinical nutrition·2026

Physiologically relevant media are associated with overlapping metabolic responses in primary human hepatocytes and Huh7 cells.

Physiological reports·2026

High Basal Skeletal Muscle Glucose Uptake in Normoglycemic and Hyperinsulinemic Overweight Men Is Coupled With an Increase in Alanine-Glucose Cycling.

Diabetes·2026

See all related articles