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Trial registered on ANZCTR


Registration number
ACTRN12622001277730
Ethics application status
Approved
Date submitted
20/09/2022
Date registered
29/09/2022
Date last updated
29/09/2022
Date data sharing statement initially provided
29/09/2022
Type of registration
Prospectively registered

Titles & IDs
Public title
The effects of acute vs. chronic blackcurrant extract supplementation on cycling performance
Scientific title
The effects of acute vs. chronic blackcurrant extract supplementation on cycling performance, physiology and respiration in trained male and female cyclists.
Secondary ID [1] 307744 0
None
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Exercise capacity 327680 0
Condition category
Condition code
Musculoskeletal 324765 324765 0 0
Normal musculoskeletal and cartilage development and function
Respiratory 324800 324800 0 0
Normal development and function of the respiratory system

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Subjects will consume blackcurrant extract (BE) powder administered in opaque, purple, berry flavoured gelatin capsules at a dose of 4.3 mg/kg body weight. Supplementation will be 60 minutes before exercise for the acute trial and for 7 days (one dose per day taken orally in gelatin capsules) before the next exercise trial. The number of placebo capsules will match the quantity needed to administer a 4.3 mg/kg body weight dose of BE. Subjects will be oversupplied with capsules and a countback will be done to ensure supplementation adherence. The exercise protocol is an incremental V'O2 max test of 3 minute stages increasing 30 watts every 3 minutes until exhaustion and/or an inability to maintain a cycling cadence of > 75 rpm. Following the completion of the incremental test, subjects will have a 15 minute rest, and then be required to complete a maximal 4 km time trial as fast as possible. All cycling tests will be performed on a calibrated cycle ergometer. Subjects will then repeat the trial after consuming an acute dose of the alternative supplement (BC/PL) and then consume a daily dose for a period of 7 days before completing the exercise protocol again. There is a 7-day washout period between chronic and acute supplementation trials.
Intervention code [1] 324461 0
Treatment: Other
Comparator / control treatment
Placebo will be an equivalent dose of dextrose powder administered in the same purple, berry flavoured, gelatin capsules at a quantity that matches the BC volume.
Control group
Placebo

Outcomes
Primary outcome [1] 332587 0
Cycling time trial performance time measured by the cycle ergometer's software (RacerMate Inc, WA, USA).
Timepoint [1] 332587 0
Immediately post completion of the 4 km time trial.
Primary outcome [2] 332588 0
Ventilatory threshold will be calculated from metabolic data obtained from a calibrated metabolic system (Metamax, Cortex, Leipzig, Germany).
Timepoint [2] 332588 0
At the completion of the incremental cycling test
Secondary outcome [1] 413994 0
Respiratory function will be assessed with spirometry testing for forced vital capacity (FVC), forced expiratory volume (FEV1), peak expiratory flow (PEF) according to the guidelines of the American Thoracic Society (2019), using a digital spirometer interfaced to a computer (Medikro Pro, Kuopio, Finland).
Timepoint [1] 413994 0
Spirometry testing will occur 10 minutes prior to exercise testing and 5 minutes post completion of the incremental ramp test and 5 minutes post the 4 km time trial.

Eligibility
Key inclusion criteria
Trained male and female cyclists with a training history of > 2 years, No chronic health conditions or respiratory conditions (i.e. asthma or exercise-induced asthma or breathlessness), no acute respiratory illness within the last month, no medications that affect respiratory, cardiovascular or immune function, and over 16 years of age
Minimum age
16 Years
Maximum age
55 Years
Sex
Both males and females
Can healthy volunteers participate?
Yes
Key exclusion criteria
None

Study design
Purpose of the study
Treatment
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Sealed opaque numbered containers
Computer generated randomisation (randomizer.org)
Allocation administered by a third party not involved with the research/study.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Computer generated randomisation (randomizer.org)
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

Recruitment
Recruitment status
Not yet recruiting
Date of first participant enrolment
Anticipated
3/10/2022
Actual
Date of last participant enrolment
Anticipated
16/01/2023
Actual
Date of last data collection
Anticipated
20/02/2023
Actual
Sample size
Target
24
Accrual to date
Final
Recruitment outside Australia
Country [1] 25016 0
New Zealand
State/province [1] 25016 0
Waikato and Hawkes Bay

Funding & Sponsors
Funding source category [1] 312013 0
University
Name [1] 312013 0
University of Auckland
Country [1] 312013 0
New Zealand
Primary sponsor type
University
Name
University of Auckland
Address
Faculty of Medical and Health Sciences (FMHS)
85 Park Road
Grafton
Auckland
1023
Country
New Zealand
Secondary sponsor category [1] 313511 0
Individual
Name [1] 313511 0
Dr Andrea Braakhuis
Address [1] 313511 0
Faculty of Medical and Health Sciences (FMHS)
85 Park Road
Grafton
Auckland
1023
Country [1] 313511 0
New Zealand

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 311433 0
Central Health and Disability Ethics Committee
Ethics committee address [1] 311433 0
Ministry of Health
133 Molesworth Street
Wellington
6011
Ethics committee country [1] 311433 0
New Zealand
Date submitted for ethics approval [1] 311433 0
12/08/2022
Approval date [1] 311433 0
20/09/2022
Ethics approval number [1] 311433 0
2022 EXP 13363

Summary
Brief summary
The mechanisms underlying performance increases following anthocyanin supplementation have not been elucidated. However, a review examining dietary anthocyanin intake postulates that performance improvements may be mediated by increases in endothelial nitric oxide and subsequent enhanced muscle blood flow (Cook & Williams, 2019). In addition, the same review highlighted that most studies reporting performance benefits utilised a chronic BE loading regime but also provided an acute dose immediately before exercise, therefore raising the question if any performance benefits were due to the intake of the final acute dose, or a result of chronic loading. Due to the lack of research examining the effects of acute versus chronic BE supplementation on exercise performance the primary aim of this research was to examine the effects of a single acute dose of blackcurrant extract (BE) on exercise performance compared to 7-day supplementation. A secondary aim is to determine if any respiratory benefits exist with supplementation, and finally if BE supplementation (acute or chronic) in healthy exercising individuals improves respiratory function. The proposed dose of blackcurrant extract is 4.3 mg/kilogram body weight. Subjects will take an acute dose of either placebo or BE 60 minutes before completing an incremental cycling test to exhaustion, followed by 15 minutes rest, and then complete a 4 km time trial. BE and PL will be administered in purple, berry flavoured gelatin capsules. Following the acute trial, subjects will supplement for 7-days and return to the lab to complete the testing again. A 7-day washout will occur before completing the protocols again but consuming the alternative supplement. Two familiarisation trials will be completed to calculate the coefficient of variation (CV ) of the exercise protocol and for subjects to become accustomed to the protocols and testing, thereby reducing any potential learning effects. There will be no supplementation at the familiarisation trials.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 121078 0
Ms Lillian Morton
Address 121078 0
University of Auckland
Faculty of Medical and Health Sciences
85 Park Road,
Grafton
Auckland
1203
Country 121078 0
New Zealand
Phone 121078 0
+64 0275190374
Fax 121078 0
Email 121078 0
[email protected]
Contact person for public queries
Name 121079 0
Lillian Morton
Address 121079 0
University of Auckland
Faculty of Medical and Health Sciences
85 Park Road,
Grafton
Auckland
1203
Country 121079 0
New Zealand
Phone 121079 0
+64 0275190374
Fax 121079 0
Email 121079 0
[email protected]
Contact person for scientific queries
Name 121080 0
Lillian Morton
Address 121080 0
University of Auckland
Faculty of Medical and Health Sciences
85 Park Road,
Grafton
Auckland
1203
Country 121080 0
New Zealand
Phone 121080 0
+64 0275190374
Fax 121080 0
Email 121080 0
[email protected]

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
No
No/undecided IPD sharing reason/comment


What supporting documents are/will be available?

No Supporting Document Provided



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.