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Trial registered on ANZCTR


Registration number
ACTRN12618001466235
Ethics application status
Approved
Date submitted
27/08/2018
Date registered
31/08/2018
Date last updated
31/08/2018
Type of registration
Retrospectively registered

Titles & IDs
Public title
The effect of single-dose beetroot juice on the blood pressure and cognition of healthy older versus younger adult
Scientific title
The effect of acute beetroot juice supplementation on the cardiovascular and cognition function of healthy older versus younger adult
Secondary ID [1] 295901 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 309370 0
Cognitive decline
309371 0
Condition category
Condition code
Cardiovascular 308232 308232 0 0
Hypertension
Neurological 308267 308267 0 0
Other neurological disorders

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Beetroot intervention:
One bottle (150ml) of nitrate-rich beetroot juice (10.5 mmol nitrate) consumed acutely 2.25 hours prior to repeating testing and 2.5 hr prior to 30 minutes of walking exercise at moderate intensity (defined as a 3 on the Borg RPE 10-point scale).
Intervention adherence will be controlled for by observing participants consume the drink in the laboratory
Wash out period between trial was one week
Intervention code [1] 312226 0
Treatment: Other
Intervention code [2] 312269 0
Other interventions
Comparator / control treatment
Placebo control:
One bottle (150ml) of nitrate-depleted beetroot juice (1 mmol nitrate) acutely, 2,25 hours prior to retesting and 2.5 hr prior to exercise. This will be done in a randomised crossover design.
Intervention adherence again will be controlled for by observing participants consume the drink in the laboratory
Control group
Placebo

Outcomes
Primary outcome [1] 307199 0
Change in blood pressure (Average of three resting blood pressure measures using an OMRON automatic blood pressure machine)
Timepoint [1] 307199 0
Before versus 2.25 hours after consumption of beetroot juice (Primary measure) and post-exercise.
Primary outcome [2] 307200 0
Plasma nitrate concentrations (via blood sample analysis with HPLC)
Timepoint [2] 307200 0
Before versus 2.25 hours after consumption of beetroot juice (primary measure) and post-exercise test
Primary outcome [3] 307230 0
Plasma nitrite concentrations (via blood sample analysis with HPLC)
Timepoint [3] 307230 0
Before versus 2.25 hours after consumption of beetroot juice (primary measure) and post-exercise test
Secondary outcome [1] 351100 0
Cognitive performance (via three cognitive tests; choice reaction test, rapid visual information processing test and Stroop test); this was a composite secondary outcome
Timepoint [1] 351100 0
Before versus 2.25 hours after consumption of beetroot juice
Secondary outcome [2] 351101 0
Cardiovascular performance (from oxygen uptake measured using Douglas bags)
Timepoint [2] 351101 0
First 5 min during 30 minute walking test
Secondary outcome [3] 351102 0
Mood and perception (using feeling scale, felt arousal scale, profile of mood states, and rating of perceived exertion scale); this was a composite secondary outcome
Timepoint [3] 351102 0
Before versus 2.25 hours after consumption of beetroot juice and during 30 minute walking test

Eligibility
Key inclusion criteria
Between the ages of 18 - 30y or 50 - 70y
Able to walk at moderate intensity for 30 min
Healthy individuals
Minimum age
18 Years
Maximum age
70 Years
Gender
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

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
Crossover
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 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, using a SD of 9, with a statistical power of 0.82 and a-level set at 0.05.

The data were 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 were applied if these assumptions were not met. Where significant differences were found, post-hoc tests with Holm-Bonferroni correction were undertaken to assess multiple comparisons. Outliers were excluded based on the Tukey test. Data are presented as mean ± standard deviation. Statistical significance was 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] 20798 0
New Zealand
State/province [1] 20798 0
Auckland

Funding & Sponsors
Funding source category [1] 300491 0
University
Name [1] 300491 0
Massey University, Auckland
Address [1] 300491 0
Massey University East Precinct, Dairy Flat Highway (SH17), Albany, Auckland, 0632
Country [1] 300491 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] 299981 0
None
Name [1] 299981 0
Address [1] 299981 0
Country [1] 299981 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 301291 0
Massey University Human Ethics Committee: Human Ethics Southern A Committee
Ethics committee address [1] 301291 0
Massey University Human Ethics Committee, Massey University, Private Bag 11 222 | Palmerston North 4442 | New Zealand
Ethics committee country [1] 301291 0
New Zealand
Date submitted for ethics approval [1] 301291 0
18/04/2016
Approval date [1] 301291 0
07/07/2016
Ethics approval number [1] 301291 0
SOA 16/27

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 effects of beetroot juice when comparing younger and older adults.

Overall aim:
Therefore, the aim of this study is to examine the effects of acute nitrate supplementation, from beetroot juice as a breakfast food, on cognition, mood and cardiovascular responses in younger (18-30) versus older adults (50-70).
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 86514 0
Mr Luke Stanaway
Address 86514 0
School of Sport, Exercise and Nutrition | College of Health
Massey University | Private Bag 102904 | North Shore Mail Centre | Auckland | 0745
Country 86514 0
New Zealand
Phone 86514 0
+642102965220
Fax 86514 0
Email 86514 0
l.stanaway@massey.ac.nz
Contact person for public queries
Name 86515 0
A/Prof Ajmol Ali
Address 86515 0
School of Sport, Exercise and Nutrition | College of Health
Massey University | Private Bag 102904 | North Shore Mail Centre | Auckland | 0745
Country 86515 0
New Zealand
Phone 86515 0
+64 9 213 6414
Fax 86515 0
Email 86515 0
a.ali@massey.ac.nz
Contact person for scientific queries
Name 86516 0
A/Prof Ajmol Ali
Address 86516 0
School of Sport, Exercise and Nutrition | College of Health
Massey University | Private Bag 102904 | North Shore Mail Centre | Auckland | 0745
Country 86516 0
New Zealand
Phone 86516 0
+64 9 213 6414
Fax 86516 0
Email 86516 0
a.ali@massey.ac.nz

No data has been provided for results reporting
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