BEE SWEET: Beetroot Supplementation in Women Enjoying Exercise Together
Study Details
Study Description
Brief Summary
This study seeks to determine the feasibility of an exercise training progression with the consumption of beetroot juice prior to exercise in postmenopausal women. Results from this investigation will be used to determine preliminary effect sizes for exercise training only (control) and exercise training + beetroot juice (EX+BR) to inform the direction of larger randomized clinical trials on pre-post changes in measures of cardiovascular health and endothelial function.
| Condition or Disease | Intervention/Treatment | Phase |
|---|---|---|
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N/A |
Detailed Description
An increasing body of evidence has supported acute benefits of beetroot juice including lowered blood pressure and greater muscle oxygenation during exercise. Thus, consumption of beetroot juice prior to exercise may alter the perceptual difficulty for a given exercise bout -- possibly resulting in an individual exercising at a greater intensity (without the commensurate increase in discomfort). The investigators propose that repeated exposure to a relatively greater exercise stimulus (via beetroot juice) may elicit more robust cardio-metabolic adaptations compared to exercise training alone (i.e., without beetroot juice). Possible findings could inform a larger randomized clinical trial to determine if pre-exercise beetroot juice supplementation is an effective strategy to promote health related benefits.
The investigators will examine the effects of pre-exercise beetroot juice coupled with 8 weeks of supervised exercise training among post-menopausal (75 and younger) women. Qualified individuals will be required to complete an initial screening visit as well as three baseline visits (Visits 1-2). Participants will undergo a series of tests including: dual-energy X-ray absorptiometry scan, bioelectrical impedance analysis, exhaled fraction of nitric oxide, health-related questionnaires, and pulse wave velocity. Participants will also be asked to perform leg muscle function and walking tests. Following the completion of Visits 1-2, participants will attend supervised exercise training sessions 3x/week for 8 weeks. Within 2-6 days from the last exercise training session, participants will repeat the same measurement procedures.
The primary objective involves elements of feasibility (e.g., recruitment, retention, adherence, and adverse event) and to generate preliminary effect sizes for 8 weeks of exercise training for two groups: control and EX+BR. Secondary objectives involve preliminary effect sizes for pre-post changes in distance covered during the 6-minute walk test, changes in endothelial-dependent vasodilation, and biomarkers of cardiovascular health.
Study Design
Arms and Interventions
| Arm | Intervention/Treatment |
|---|---|
| Active Comparator: Ex only Participants will perform 8 weeks of supervised exercise training (EX). |
Other: Exercise Training
Participants will perform 8 weeks of supervised exercise training at a frequency of 3x per week.
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| Experimental: EX + BR Participants will perform 8 weeks of supervised exercise training (EX) plus pre-exercise consumption of beetroot juice (BR). |
Dietary Supplement: Beetroot Juice
Participants randomly assigned to the EX + BR group will consume 140 mL beetroot juice containing approximately 12 mmol of nitrate 3 hours prior to the supervised exercise training component.
Other: Exercise Training
Participants will perform 8 weeks of supervised exercise training at a frequency of 3x per week.
|
Outcome Measures
Primary Outcome Measures
- Recruitment rate [24 months]
The number of eligible participants randomized per months of recruitment time.
- Retention rate [8 weeks]
The number of randomized participants who complete at least 17 (out of 24 possible) exercise training sessions.
- Adherence to exercise training intervention [8 weeks]
The percent of exercise sessions attended out of the 24 possible sessions.
- Adherence to dietary nitrate intervention [8 weeks]
Breath analysis of fractional exhaled nitric oxide concentrations.
- Perceived difficulty of training sessions [8 weeks]
Participants will report the perceived exertion at the end of exercise sessions using the Borg category ratio-10 scale that ranges from 0 "no exertion" to 10 "maximal exertion".
Secondary Outcome Measures
- Distance covered during a six-minute walk test [Baseline, post-intervention]
Participants will be asked to walk as far as possible at a preferred speed for six minutes according to ATS standards. Distance covered will be measured in meters.
- Soluble endothelial microparticles [Baseline, post-intervention]
Blood samples will be analyzed for adhesion molecules (sICAM-1, sVCAM-1, sE-selectin).
Eligibility Criteria
Criteria
Inclusion Criteria:
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Post-menopausal women (self-report)
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Between the ages of 18-75 years (confirmed by birth date listed on participant's driver license at screening visit)
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Physician's clearance for study participation (required prior to baseline testing)
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English-speaking
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Body mass index between 25.0 to 39.9 kg/m^2 (measured on-site at screening visit)
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Able to ambulate without assistance
Exclusion Criteria:
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Unable to provide informed consent
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18-75 of age (confirmed by birth date listed on participant's driver license at screening visit)
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Body mass index < 25.0 or >39.9 kg/m^2 (measured on-site at screening visit)
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Greater than stage II hypertension (i.e. >159/99 mm Hg)
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Current smoker (self-report)
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Currently pregnant, lactating, or trying to become pregnant (self-report)
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Habitually exercise training >= 3 times per week (self-report)
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Significant orthopedic limitations or other contraindications to strenuous exercise
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Live or work >50 miles from Bloomington study site or do not have transportation to the study site
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Anticipate elective surgery during the study period
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Plan to move residence or travel out of the local area during the study period
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History of major metabolic disease (e.g. Type I diabetes, Type II diabetes, thyroid disorders)
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Current use of anti-coagulants (e.g. Coumadin or Warfarin)
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Current use of prescription medications that affect heart rate or blood vessel dilation (e.g. phosphodiesterase-5 inhibitors, proton pump inhibitors, systemic adrenergic blockers, nitrates, calcium channel blockers, hormone replacement therapy) (self-report and confirmed on-site at screening visit)
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Psychological or social characteristic that would interfere with their ability to fully participate in the study (i.e. taking longer than allowed time to complete cognitive assessments)
Contacts and Locations
Locations
| Site | City | State | Country | Postal Code | |
|---|---|---|---|---|---|
| 1 | Indiana University | Bloomington | Indiana | United States | 47401 |
Sponsors and Collaborators
- Indiana University
- IU Health University Hospital
- Indiana CTSI Clinical Research Center
- Bloomington Crossfit
Investigators
- Principal Investigator: Stephen J Carter, Ph.D., Indiana University Bloomington
Study Documents (Full-Text)
More Information
Publications
None provided.- 1907026303