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Trial registered on ANZCTR


Registration number
ACTRN12609000522213
Ethics application status
Approved
Date submitted
21/06/2009
Date registered
1/07/2009
Date last updated
1/07/2009
Type of registration
Retrospectively registered

Titles & IDs
Public title
Effect of glycemic index on substrate oxidation and food intake
Scientific title
Effect of glycemic index on substrate oxidation and food intake in male cyclists
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Obesity 237071 0
Condition category
Condition code
Metabolic and Endocrine 237392 237392 0 0
Normal metabolism and endocrine development and function

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Two daily high glycemic index meals (breakfast and lunch). Participants are consuming corn flake cereal, whole milk, sports drink (high carbohydrate, water, and electrolytes replenisher), white bread, and margarine for the high glycemic index meal (glycemic index = 79). All Bran cereal, fat-free strawberry yogurt, grape juice, multi-grain bread, margarine, and apple are being provided in the low glycemic index meal (glycemic index = 28).
Intervention code [1] 236790 0
Prevention
Comparator / control treatment
Two daily low glycemic index meals (breakfast and lunch). Participants are consuming corn flake cereal, whole milk, sports drink (high carbohydrate, water, and electrolytes replenisher), white bread, and margarine for the high glycemic index meal(glycemic index = 79). All Bran cereal, fat-free strawberry yogurt, grape juice, multi-grain bread, margarine, and apple are being provided in the low glycemic index meal (glycemic index = 28).
Control group
Active

Outcomes
Primary outcome [1] 238191 0
Fat oxidation will be estimated with the oxygen consumption (VO2) and the carbon dioxide excretion (VCO2) values obtained through indirect calorimetry, using the Frayn (1983) equation.
Timepoint [1] 238191 0
At baseline and on day 5 of the test meal consumption (once a day)
Primary outcome [2] 238192 0
Energy intake assessed by food diary
Timepoint [2] 238192 0
At baseline (the week before participating in the study) and 24 h after the consumption of the last test meal on day 5
Secondary outcome [1] 242498 0
Respiratory exchange ratio will be assessed by indirect calorimetry
Timepoint [1] 242498 0
Baseline and on day 5 of the high glycemic and the low glycemic index sessions

Eligibility
Key inclusion criteria
Cyclists should exercise at least three times a week, no alcohol consumption, nonsmokers, no use of medication, not on a therapeutic diet, normal blood pressure, and dietary restraint scores less than 14 based on a restraint scale (Stunkard, & Messick, 1985).
Minimum age
18 Years
Maximum age
40 Years
Gender
Males
Can healthy volunteers participate?
Yes
Key exclusion criteria
Non-cyclists, alcohol consumers, smokers, on medication, on a therapeutic diet, high blood pressure, and dietary restraint scores higher than 14 based on a restraint scale (Stunkard, & Messick, 1985).

Study design
Purpose of the study
Prevention
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Masking / blinding
Who is / are masked / blinded?



Intervention assignment
Other design features
Phase
Type of endpoint(s)
Statistical methods / analysis

Recruitment
Recruitment status
Active, not recruiting
Date of first participant enrolment
Anticipated
Actual
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
Actual
Sample size
Target
Accrual to date
Final
Recruitment outside Australia
Country [1] 1847 0
Brazil
State/province [1] 1847 0

Funding & Sponsors
Funding source category [1] 237188 0
Government body
Name [1] 237188 0
FAPEMIG - Fundacao de Amparo a Pesquisa do Estado de Minas Gerais
Address [1] 237188 0
Rua Raul Pompeia 101-Sao Pedro - CEP: 30.330-080 - Belo Horizonte - Minas Gerais
Country [1] 237188 0
Brazil
Primary sponsor type
University
Name
Universidade Federal de Vicosa
Address
Departamento de Nutricao e Saude - Avenida PH Rolfs, s/n
Vicosa - MG 36570-000
Country
Brazil
Secondary sponsor category [1] 4681 0
None
Name [1] 4681 0
Address [1] 4681 0
Country [1] 4681 0

Ethics approval
Ethics application status
Approved

Summary
Brief summary
The study will be conducted to test the hypothesis that consuming low glycemic index meals will lead to greater fat oxidation during the postprandial period and subsequent high-intensity exercise than consuming high glycemic index meals will.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 29778 0
Address 29778 0
Country 29778 0
Phone 29778 0
Fax 29778 0
Email 29778 0
Contact person for public queries
Name 13025 0
Rita Alfenas
Address 13025 0
Universidade Federal de Vicosa - Departamento de Nutricao e Saude - Avenida PH Rolfs, s/n
Vicosa - MG
36570-000
Country 13025 0
Brazil
Phone 13025 0
+55 31 3899 3740
Fax 13025 0
Email 13025 0
ralfenas@ufv.br
Contact person for scientific queries
Name 3953 0
Rita Alfenas
Address 3953 0
Universidade Federal de Vicosa - Departamento de Nutricao e Saude - Avenida PH Rolfs, s/n
Vicosa - MG
36570-000
Country 3953 0
Brazil
Phone 3953 0
+55 31 3899 3740
Fax 3953 0
Email 3953 0
ralfenas@ufv.br

No information has been provided regarding IPD availability
Summary results
Have study results been published in a peer-reviewed journal?
Other publications
Have study results been made publicly available in another format?
Results – basic reporting
Results – plain English summary