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Trial registered on ANZCTR


Registration number
ACTRN12624000060549
Ethics application status
Approved
Date submitted
15/12/2023
Date registered
25/01/2024
Date last updated
25/01/2024
Date data sharing statement initially provided
25/01/2024
Date results information initially provided
25/01/2024
Type of registration
Retrospectively registered

Titles & IDs
Public title
High carbohydrate diets with varied FODMAP content on the development of exercise-associated gastrointestinal symptoms during endurance exercise in endurance-trained athletes
Scientific title
The impact of dietary FODMAP content on markers of exercise-induced gastrointestinal syndrome in endurance-trained athletes.
Secondary ID [1] 311187 0
None
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Gut disturbance during exercise 332365 0
Condition category
Condition code
Oral and Gastrointestinal 329071 329071 0 0
Normal oral and gastrointestinal development and function
Diet and Nutrition 329072 329072 0 0
Other diet and nutrition disorders

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Participants are provided with a high carbohydrate high FODMAP (HC-HFOD) or high carbohydrate low FODMAP (HC-LFOD) diet 48-h before endurance exercise. The HC-HFOD is the comparator diet, and the HC-LFOD is the intervention.
The HC-HFOD diet provided was 813 g +/- 101 g total carbohydrate daily (11.3 +/- 1.0 g/kg bodyweight/d) or 72% of carbohydrate with a high FODMAP load (54.8 +/- 10.5 g daily). The HC-LFOD diet provided was 888 g +/- 71 g total carbohydrate daily (12.6 +/- 2.0 g/kg bodyweight/d) or 73% of carbohydrate with a low FODMAP load (3.0 +/- 0.2 g daily).
Participants were provided with all meals, snacks, and drinks, excluding water, for the 48-h prior to the exercise test and the test day breakfast. Meals were designed, prepared and administered by a research registered dietitian.
Examples of the meals and snacks for the diets are:
HC-HFOD diet (note the HC-LFOD diet has a similar meal pattern except all HFOD meals or snacks were designed to be LFOD - e.g., LFOD fruity oats - had less sugar and less raisins or cows milk was replaced for lactose-free milk).
Breakfast:
HFOD fruity oats (oats, quinoa, raisins, brown sugar)
Low-fat cow’s milk (1%) (250 mL)
Greek yoghurt (200 g)
Honey (25 g)
Morning Tea:
Spelt sourdough bread (2 slices)
Butter (10 g)
Strawberry jam (10 g)
Kiwifruit (2 medium green fruit)
Lunch:
HFOD vegetable soup (red capsicum, zucchini, carrot, corn, barley, potato, LFOD stock cubes, garlic, onion)
Spelt sourdough bread (2 slices)
Greek yoghurt (200 g)
Afternoon Tea:
Orange (1 medium fruit)
HFOD creamed rice (white rice, white sugar, low-fat cow’s milk, butter, vanilla essence, cinnamon)
Dinner:
HFOD meat sauce (beef mince, tomato pasta, canned tomatoes, carrot, olive oil, onion, garlic, salt)
Wheat pasta cooked (400 g)
Cheddar cheese grated (30 g)
Cranberry juice (300 mL)
Supper:
Cranberry juice (300 mL)
Raisins (40 g)
Drinks:
Powerade (about 2L daily)
Plus additional Dextrose (if required)
Smoothie (Low-fat cow’s milk, dextrose, protein powder, blueberries, honey).
Pre-Exercise breakfast of trial days was the same for both trials:
LFOD fruity oats
Lactose-free yoghurt (200 g)
Lactose-free cow’s milk (250 mL)
Maple syrup (25 g)

Participants received the diet for 48-h before exercise (i.e., 2 days before) and the breakfast for the trial day. During the 3-h seated recovery period, participants were provided with a recovery meal (after 2 -h), plus some fruit. The diets were based on a carbohydrate loading protocol (or high carbohydrate diet), as recommended for endurance athletes by sports nutrition guidelines. Diets were based on 10-12g carbohydrate/kg of body mass; only the FODMAP content varied between diets. To ensure food adherence, participants monitored all food and drink consumed in a food log. A research dietitian reviewed and confirmed the food log with participants. As this was a cross-over trial, there was a wash-out period of 7 days between trials.
Intervention code [1] 327634 0
Lifestyle
Comparator / control treatment
The comparator is the high carbohydrate high FODMAP trial.
Control group
Active

Outcomes
Primary outcome [1] 336879 0
Difference in plasma intestinal fatty acid binding protein
Timepoint [1] 336879 0
Before exercise (baseline pimary start point), After exercise, 1 hr post-exercise (primary endpoint) and 2 hr post-exercise.
Secondary outcome [1] 430027 0
Differences in the perceived severity of exercise-associated gastrointestinal symptoms developed during endurance exercise.
Timepoint [1] 430027 0
Baseline (before exercise): every 15 minutes during exercise, post-exercise (in the recovery period), and every 15 minutes for 120 minutes during recovery.

Eligibility
Key inclusion criteria
Key inclusion criteria:
The Inclusion criteria for the study is healthy male and female recreationally competitive endurance runners 18 – 50 years of age, with pre-existing exercise-associated gastrointestinal symptoms.
Only non-pregnant, non-breastfeeding women will participate during day 5 – 10 of the follicular phase of the menstrual cycle confirmed with testing serum estradiol, urinal and calendar-based counting of menstrual diary records (or through a menstrual app) (Gaskell et al, 2020, Snipe et al, 2018). This is to ensure hormonal levels are consistent at each experimental trial, and to reduce any risks that may cause harm to an unborn baby or fluctuations in hormonal levels experienced during breastfeeding.
Minimum age
18 Years
Maximum age
50 Years
Sex
Both males and females
Can healthy volunteers participate?
Yes
Key exclusion criteria
Individuals presenting clinical diagnosis of gastrointestinal disease or disorders or individuals presenting any other forms of illness or disease due to confounding effects on gastrointestinal markers/outcomes. Individuals presenting soft tissue injury 1 month prior to participation due to the risk of re-occurrence of injury.
Exclusion criteria will be participants who have been following a dietary programme focussed on any changes to the GI function (e.g., a low FODMAP diet, low residue, or fibre-modified diets), or carbohydrate-manipulated diets (i.e., low carbohydrate high fat or ketogenic diets, within the last six months) or have been consuming any potential modifiers or enhancers of the GI integrity (e.g., probiotics, pre-biotics, symbiotic, or antibiotics) in the three months prior to testing. Participants who have a diagnosed food allergy will also be excluded due to potential allergens present in experimental foods or potential cross-contamination with the food manufacturing process of the experimental foods.
Participants will also be excluded if they have any GI infections, diseases, or disorders of the GI tract (e.g., IBS, inflammatory bowel disease, coeliac disease, diverticular disease, gastro-oesophageal reflux, or any other self-reported GI issues). If participants have consumed any non-steroidal antiinflammatory or stool-altering medications (e.g., laxatives, anti-diarrhoeal or stool softeners) within one month of the experimental protocols they will be excluded. Participants will also refrain from consuming any of the above whilst on the trial.

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)
Central randomization by computer
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Simple randomisation using a randomisation table created by computer software (i.e. computerised sequence generation)
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?
The people receiving the treatment/s
The people administering the treatment/s
The people assessing the outcomes
Intervention assignment
Crossover
Other design features
Phase
Not Applicable
Type of endpoint/s
Efficacy
Statistical methods / analysis
A G-Power (V.3.1.9.7) (RRID:SCR_01376) calculation is used to determine sample size based on mean differences in I-FABP responses with high and low FODMAP diets (Gaskell et al., 2020). Using a standard alpha of (0.05) and beta value of (0.80), a sample size of 11 was estimated to provide adequate statistical power to detect significant trial differences within a randomized crossover design. Data in text and tables will be presented as mean ± standard deviation (SD) or 95% confidence interval (CI), as stated. As previously reported (Gaskell et al., 2020, Snipe et al., 2018a), a summative accumulation of the severity rating score, with individual participant ranges for gastrointestinal symptoms (GIS), will be used. For clarity, data in figures will be presented as mean ± standard error of the mean (SEM). Before data analysis, potential outliers will be identified by box and whisker plots and removed and removed. All data will be checked for normal distribution using the Shapiro-Wilks test for normality checking skewness and kurtosis coefficients. Continuous data with singular data points will be analyzed using paired sample t-tests (or nonparametric Wilcoxon signed-rank test equivalents), while variables with multiple data points were examined using a two-way repeated-measures analysis of variance (ANOVA). Assumptions of homogeneity and sphericity were checked, and appropriate adjustments to the degrees of freedom are made using the Greenhouse–Geisser correction method. Significant main effects were analyzed using a post-hoc Tukey's HSD test. Cohen's standardized measurement of effect size between trials for GIS was determined as d = 0.20, d = 0.50, and d = 0.80 for small, medium, and large effects, respectively. Statistics will be analyzed using IBM SPSS statistical software (V.29.0, IMB Corp., Armonk, N.Y., USA), with significance accepted at p = 0.05.

Recruitment
Recruitment status
Completed
Date of first participant enrolment
Anticipated
Actual
1/02/2022
Date of last participant enrolment
Anticipated
Actual
1/08/2022
Date of last data collection
Anticipated
Actual
17/12/2022
Sample size
Target
12
Accrual to date
Final
12
Recruitment in Australia
Recruitment state(s)
VIC

Funding & Sponsors
Funding source category [1] 315445 0
University
Name [1] 315445 0
Monash University
Country [1] 315445 0
Australia
Funding source category [2] 315446 0
University
Name [2] 315446 0
University of the Sunshine Coast
Country [2] 315446 0
Australia
Funding source category [3] 315447 0
Other
Name [3] 315447 0
Toi Ohomai
Country [3] 315447 0
New Zealand
Primary sponsor type
University
Name
Monash University
Address
264 Ferntree Gully Road, Notting Hill, VIC 3168
Country
Australia
Secondary sponsor category [1] 317518 0
University
Name [1] 317518 0
Univesity of the Sunshine Coast
Address [1] 317518 0
90 Sippy Downs Road, Sippy Downs, QLD
Country [1] 317518 0
Australia

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 314356 0
Monash University Human Research Ethics Committee
Ethics committee address [1] 314356 0
Wellington Rd, Clayton VIC 3800, Australia
Ethics committee country [1] 314356 0
Australia
Date submitted for ethics approval [1] 314356 0
06/07/2021
Approval date [1] 314356 0
07/07/2021
Ethics approval number [1] 314356 0
28804
Ethics committee name [2] 314357 0
University of the Sunshine Coast Human Reserach Ethics Committee
Ethics committee address [2] 314357 0
90 Sippy Downs Drive, Sippy Down, QLD
Ethics committee country [2] 314357 0
Australia
Date submitted for ethics approval [2] 314357 0
08/02/2022
Approval date [2] 314357 0
10/02/2022
Ethics approval number [2] 314357 0
S221685

Summary
Brief summary
The purpose of this research study is to investigate the impact of carbohydrate loading with high and low FODMAP diets on markers of gastrointestinal integrity, function, symptoms and performance implications in response to endurance exercise. FODMAPs are short chain fermentable carbohydrates (e.g., lactose, fructose, fructans, galactans and polyalcohols), which are transported slowly in the small intestine and are rapidly fermentable by the colonic microbiota. This fermentation can lead to bloating, visceral hypersensitivity and/or a change in gut motility. To determine any gastrointestinal changes, this will be achieved through the consumption of a high carbohydrate diet with high or low FODMAPs 48-hours before two hours of continuous running, following by a one-hour performance test.

Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 131298 0
A/Prof Ricardo da Costa
Address 131298 0
BASES facility, Nutrition and Dietetics, Monash University, 264 Ferntree Gully Rd, Notting Hill VIC 3168, Australia
Country 131298 0
Australia
Phone 131298 0
+61 3 99056861
Fax 131298 0
Email 131298 0
Ricardo.Costa@monash.edu
Contact person for public queries
Name 131299 0
A/Prof Ricardo da Costa
Address 131299 0
BASES facility, Nutrition and Dietetics, Monash University, 264 Ferntree Gully Rd, Notting Hill VIC 3168, Australia
Country 131299 0
Australia
Phone 131299 0
+61 3 99056861
Fax 131299 0
Email 131299 0
Ricardo.Costa@monash.edu
Contact person for scientific queries
Name 131300 0
A/Prof Ricardo da Costa
Address 131300 0
BASES facility, Nutrition and Dietetics, Monash University, 264 Ferntree Gully Rd, Notting Hill VIC 3168, Australia
Country 131300 0
Australia
Phone 131300 0
+61 3 99056861
Fax 131300 0
Email 131300 0
Ricardo.Costa@monash.edu

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
Yes
What data in particular will be shared?
After de-identification, data that will be shared will be any demographic data, physiological variables, gastrointestinal integrity, and function data, and any gastrointestinal symptom data.
When will data be available (start and end dates)?
Immediately following publication, no end date.
Available to whom?
Case-by-case basis at the discretion of the Primary Sponsor (Ricardo Costa)
Available for what types of analyses?
Only to achieve the aims in the approved proposal.
How or where can data be obtained?
Access is subject to approval by the Principal Investigator (ricardo.costa@monash.edu).


What supporting documents are/will be available?

Doc. No.TypeCitationLinkEmailOther DetailsAttachment
21212Informed consent form  ricardo.costa@monash.edu 387060-(Uploaded-15-12-2023-08-50-39)-Study-related document.doc
21213Ethical approval  ricardo.costa@monash.edu 387060-(Uploaded-15-12-2023-08-52-42)-Study-related document.pdf



Results publications and other study-related documents

Documents added manually
No documents have been uploaded by study researchers.

Documents added automatically
No additional documents have been identified.