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Trial registered on ANZCTR


Registration number
ACTRN12620000081910
Ethics application status
Approved
Date submitted
21/11/2019
Date registered
31/01/2020
Date last updated
29/06/2021
Date data sharing statement initially provided
31/01/2020
Date results information initially provided
29/06/2021
Type of registration
Retrospectively registered

Titles & IDs
Public title
Effects of short-term and prolonged supplementation of beetroot juice on cardiovascular and cognitive function and mood of healthy older compared to younger adults
Scientific title
The effects of acute and chronic nitrate supplementation, of beetroot juice, on cognition, mood and cardiovascular responses in younger (18-30) versus older adults (50-80).
Secondary ID [1] 295890 0
None
Universal Trial Number (UTN)
Trial acronym
TBJP (The Beetroot Juice Project)
Linked study record

Health condition
Health condition(s) or problem(s) studied:
High Blood Pressure 309363 0
Cognitive decline 309364 0
Cardiovascular disease 309372 0
Condition category
Condition code
Cardiovascular 308229 308229 0 0
Hypertension
Cardiovascular 308233 308233 0 0
Coronary heart disease
Neurological 313586 313586 0 0
Other neurological disorders

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Beetroot intervention:
One bottle (250ml) of nitrate-rich beetroot juice (10.5 mmol nitrate) consumed once daily for 28 days.
Intervention adherence will be controlled for by having participants return all empty bottle to the head researcher who will double-check labelling and number. In total participants will complete 5 trials: a familiarisation trial, a cycle trial, and three supplementation trials. The familiarisation and cycle trial will occur within two weeks of each other and at least 2 days apart to ensure they are still familiar with tests and that they are not still fatigue from the familiarisation trial. The cycle trial and first supplementation trial will be separated by one week and the 3 supplementation trials will occur on day 1, 14 and 28 of supplementation. The familiarisation trial will be used to familiarise the participant with the procedures and equipment, and an incremental cycle test will be completed at the end to work out their work rate max and set the amount of work required for them to complete in the cycle test for the next 4 trials (this is based on 75% of their max for 20min). During the cycle trial baseline measures of blood pressure, heart rate, systemic vascular resistance and mean arterial pressure (USCOM 1A) cognitive function, cerebral near-infrared spectroscopy, perceptual and mood tests were completed (Noted somewhere practice measure how to state). This was followed by the exercise test which was a work done time trial on the cycle (complete a predetermined work as fast as possible). For the supplementation trials, prior to consumption of the beverage, baseline measures will be completed as above followed by a collection of a resting blood sample. Participants then consumed the allocated drink with breakfast and remain in the laboratory for a 2.25 h absorption period. After 2.25 h, the aforementioned measurements were repeated prior to commencing the exercise protocol which will be that same cycle as the in the cycle trial. Following the completion of the cycle test baseline measures of blood pressure, heart rate, perceptual and mood tests, and blood sample were repeated.
Intervention code [1] 312224 0
Treatment: Other
Comparator / control treatment
Placebo control:
One bottle (250ml) of nitrate-depleted beetroot juice (1 mmol nitrate) consumed once daily for 28 days. This will be done in a randomised control trial fashion.
Intervention adherence again will be controlled for by having participants return all empty bottle to the head researcher who will double check labelling and number
Control group
Placebo

Outcomes
Primary outcome [1] 307197 0
Cardiovascular function (change in mean arterial pressure and systemic vascular resistance via USCOM)
composite outcome
Timepoint [1] 307197 0
Before versus 2.25 hours after consumption of beetroot juice on days 1, 14, and 28 [Primary timepoint]
Primary outcome [2] 307201 0
Cognitive function (Cognitive testing and functional near-infrared spectroscopy) cognitive testing included the Corsi block tapering test, rapid visual information processing test, and the Stroop test.
Composite
Timepoint [2] 307201 0
Before versus 2.25 hours after consumption of beetroot juice on days 1, 14, and 28 [Primary timepoint]
Primary outcome [3] 322040 0
Blood Pressure (deluxe HEM-7130; OMRON automatic blood pressure machine)
Timepoint [3] 322040 0
Before versus 2.25 hours after consumption of beetroot juice (primary measure) and post-exercise test
The exercise test is complete on trial two, cycle trial and trials 3, 4, and 5 (the three supplementation trials where plasma nitrate and nitrite will be measured at the above time points
Will be completed on cycle trial, and all three supplementation trials (Day 1,14, and 28)
Secondary outcome [1] 351103 0
Cycle work done time-trial performance (using Velotron cycle)
This is a Performance outcome (cycle completion time) To assess cardiovascular health
Timepoint [1] 351103 0
End of cycle time-trial
The exercise test is complete on trial two, cycle trial and trials 3, 4, and 5 (the three supplementation trials where time to completion will be recorded at the end of each of the exercise tests.
Secondary outcome [2] 351104 0
Mood
(mood scales; the profile of mood states, feeling scale and felt arousal scale will be used for mood)
Composite outcome
Timepoint [2] 351104 0
Assessed on days 1, 14, and 28; before versus 2.25 hours after consumption of beetroot juice and during cycle trial (every 20%)
The exercise test is complete on trial two, cycle trial and trials 3, 4, and 5 (the three supplementation trials, where feeling and felt arousal scales will be recorded every 20% complete of total work in the work to completion cycle trial.
Secondary outcome [3] 377938 0
Plasma nitrate and nitrite concentrations (via blood sample analysis with HPLC)
composite outcome
Timepoint [3] 377938 0
Before versus 2.25 hours after consumption of beetroot juice and post-exercise test on days 1, 14, and 28 of supplementation (trials 3, 4, and 5)
The exercise test is complete on trial two, cycle trial (no bloods taken) and trials 3, 4, and 5 (the three supplementation trials where plasma nitrate and nitrite will be measured at the above time points
Secondary outcome [4] 377939 0
Oxygen uptake kinetics (using COSMED analysis)
exploratory outcome
Timepoint [4] 377939 0
During cycle time-trial (every 10 sec)
The exercise test is complete on trial two, cycle trial and trials 3, 4, and 5 (the three supplementation trials where oxygen uptake will be measured in 10-second intervals using he mixing chambers throughout the duration of the cycle
Secondary outcome [5] 378329 0
Perception
Rating of perceived exertion (RPE) will be used for preception)
Timepoint [5] 378329 0
During cycle time-trial (every 20%)
The exercise test is complete on trial two, cycle trial and trials 3, 4, and 5 (the three supplementation trials where RPE will be recorded every 20% complete of total work in the work to completion cycle trial.

Eligibility
Key inclusion criteria
Between the ages of 18 - 30y or 50 - 80y
Able to cycle for approximately 20 min
Healthy individuals
Non-smokers
Minimum age
18 Years
Maximum age
80 Years
Sex
Both males and females
Can healthy volunteers participate?
Yes
Key exclusion criteria
Advanced/elite athletes (someone who trains more than four times per week constantly for their sport and competes at a high level)
Taking blood pressure medication
Smokers

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)
Numbered containers
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
The people analysing the results/data
Intervention assignment
Parallel
Other design features
Phase
Phase 3
Type of endpoint/s
Efficacy
Statistical methods / analysis
A power analysis was conducted (G-Power 3.1) to calculate the sample size based on the primary measure of blood pressure. Previous literature in healthy adults has shown a mean change in BP of 10 mmHg (9 SD) between BR and control. Based on this, the required sample size was 11 per group (24 per age group, 12 beetroot juice, 12 placebo), using a SD of 9, with a statistical power of 0.82 and a-level set at 0.05.

The data will be analysed using mixed-method repeated-measures analysis of variance (ANOVA) with treatment and time as within-subject factors, and age as the between-subject factor. Sphericity was tested using the Mauchly’s test to ensure the assumption of sphericity was not violated, and multivariate models will be applied if these assumptions are not met. Where significant differences are found, post-hoc tests with Holm-Bonferroni correction will be undertaken to assess multiple comparisons. Outliers will be excluded based on the Tukey test. Data will be presented as mean ± standard deviation. Statistical significance is set at P<0.05.

Recruitment
Recruitment status
Completed
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] 22135 0
New Zealand
State/province [1] 22135 0
Auckland

Funding & Sponsors
Funding source category [1] 300484 0
University
Name [1] 300484 0
Massey University, Auckland
Country [1] 300484 0
New Zealand
Primary sponsor type
University
Name
Massey University
Address
School of Sport, Exercise and Nutrition, East Precinct, Dairy Flat Highway (SH17), Albany, Auckland, 0632
Country
New Zealand
Secondary sponsor category [1] 304582 0
None
Name [1] 304582 0
Address [1] 304582 0
Country [1] 304582 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 301285 0
Massey University Human Ethics Committee: Human Ethics Southern A Committee
Ethics committee address [1] 301285 0
Massey University Human Ethics Committee, Massey University, Private Bag 11 222 | Palmerston North 4442 | New Zealand
Ethics committee country [1] 301285 0
New Zealand
Date submitted for ethics approval [1] 301285 0
23/06/2017
Approval date [1] 301285 0
25/08/2017
Ethics approval number [1] 301285 0
SOA 17/36

Summary
Brief summary
In today's society, rates of disease and age-related dysfunction continue to grow at a rapid speed. This has led to an increased interest in the use of food-based supplements such as beetroot juice. Beetroot juice contains nitrate and has been shown to reduce blood pressure, improve cardiovascular function and improve exercise performance. Furthermore, recent evidence has indicated that increased nitric oxide (the bio-active form of nitrate) may have effects on increased blood flow to the brain leading to improved cognition and mood in older adults. However, research in this area is limited and few studies have looked at the prolonged effects of nitrate-rich beetroot juice supplementation when comparing younger and older adults.

Overall aim:
Therefore the aims of this studies are to examine the effects of acute and chronic nitrate supplementation, from beetroot juice, on cognition, mood and cardiovascular responses in younger (18-30) versus older adults (50-80). Secondly, to investigate the potential mechanisms behind these effects.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 86490 0
Mr Luke Stanaway
Address 86490 0
School of Sport, Exercise and Nutrition | College of Health Massey University | Private Bag 102904 | North Shore Mail Centre | Auckland | 0745
Country 86490 0
New Zealand
Phone 86490 0
+642102965220
Fax 86490 0
Email 86490 0
Contact person for public queries
Name 86491 0
A/Prof Ajmol Ali
Address 86491 0
School of Sport, Exercise and Nutrition | College of Health Massey University | Private Bag 102904 | North Shore Mail Centre | Auckland | 0745
Country 86491 0
New Zealand
Phone 86491 0
+64 9 213 6414
Fax 86491 0
Email 86491 0
Contact person for scientific queries
Name 86492 0
A/Prof Ajmol Ali
Address 86492 0
School of Sport, Exercise and Nutrition | College of Health Massey University | Private Bag 102904 | North Shore Mail Centre | Auckland | 0745
Country 86492 0
New Zealand
Phone 86492 0
+64 9 213 6414
Fax 86492 0
Email 86492 0

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
No
No/undecided IPD sharing reason/comment
Only mean and standard deviation data will be available (via the subsequent publications)


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.