Carbohydrate Metabolism at Exercise Clinical Trial
Official title:
Disposal of Oral Fructose During Exercise
| Verified date | February 2013 |
| Source | University of Lausanne |
| Contact | n/a |
| Is FDA regulated | No |
| Health authority | Switzerland: Ethikkommission |
| Study type | Observational |
There is evidence that total carbohydrate oxidation during exercise is higher after
ingestion of fructose:glucose mixture than after ingestion of equimolar amounts of glucose
alone. This may possible contribute to improve performance, provided that the extra
carbohydrate oxidation induced by fructose:glucose co-ingestion occurs in skeletal muscle.
The present study aims at assessing the hypothesis that, during exercise, a substantial
portion of oral fructose is converted into lactate prior to oxidation To identify the major
pathways of fructose disposal, 7 healthy endurance trained male volunteers will be studied.
For each participant the following measurement will be performed
- a measurement of maximal oxygen consumption (VO2 max) on an ergometric bicycle
- a 2 hour exercise protocol with oral administration of a glucose drink. 6,6-2H2 glucose
(0.44 µmol/kg/min) and 13C3 lactate (2.25 µmol/kg/min) will be infused to calculate
glucose and lactate kinetics. Indirect calorimetry will be performed to measure total
carbohydrate oxidation and expired 13CO2 will be monitored to calculate whole body
lactate oxidation
- a 2 hour exercise protocol with oral administration of a glucose:fructose (72 + 48 g
every hour) mixture. 6,6-2H2 glucose (0.44 µmol/kg/min) and 13C3 lactate (2.25
µmol/kg/min) will be infused to calculate glucose and lactate kinetics. Indirect
calorimetry will be performed to measure total carbohydrate oxidation and expired 13CO2
will be monitored to calculate whole body lactate oxidation
- a 2 hour exercise protocol with oral administration of a glucose:fructose (72 + 48 g
every hour) mixture with fructose labelled with 13C6 fructose to evaluate exogenous
fructose metabolic fate and oxidation. 6,6-2H2 glucose (0.44 µmol/kg/min) will be
infused to calculate glucose kinetics. Fructose conversion into lactate and glucose
will be evaluated by monitoring the systemic appearance of plasma 13C-labelled lactate
and 13C-labelled glucose. Total exogenous fructose oxidation will be measured by
monitoring 13CO2 production.
Based on these measurements, semi-quantitative estimates of total fructose oxidation,
fructose conversion into glucose, fructose conversion into lactate, and oxidation of
fructose-derived lactate will be obtained
| Status | Completed |
| Enrollment | 7 |
| Est. completion date | March 2010 |
| Est. primary completion date | December 2009 |
| Accepts healthy volunteers | Accepts Healthy Volunteers |
| Gender | Male |
| Age group | 18 Years to 35 Years |
| Eligibility |
Inclusion Criteria: - age between 18 and 35 years - males - good physical health - weekly cycling training sessions (> 3 sessions/week) Exclusion Criteria: - diabetes or glucose intolerance - past history of heart disease - alcohol intake > 30 g/day - smokers - drug consumption |
N/A
| Country | Name | City | State |
|---|---|---|---|
| Switzerland | Centre Hospitalier Universitaire Vaudois | Lausanne |
| Lead Sponsor | Collaborator |
|---|---|
| University of Lausanne |
Switzerland,
| Type | Measure | Description | Time frame | Safety issue |
|---|---|---|---|---|
| Primary | Fructose conversion into lactate | during a 2 hour-exercise at 60% VO2 max | No | |
| Secondary | Total exogenous fructose oxidation | during a 2 hour-exercise at 60% VO2 max | No | |
| Secondary | Fructose conversion into glucose | during a 2 hour-exercise at 60% VO2 max | No | |
| Secondary | Oxidation of lactate derived from fructose | during a 2 hour-exercise at 60% VO2 max | No |