Nitrate Supplementation and Muscle Blood Flow

Study Overview
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Brief Summary
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The main purpose of this study is to evaluate the effects of an acute dose of dietary nitrate in the form of beetroot juice on skeletal muscle blood flow in response to dynamic knee extension exercise in healthy older adults. All subjects will receive active (rich in dietary nitrate) or placebo (devoid of nitrate) supplementation.

Detailed Description
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Dietary nitrate (beetroot juice) is reduced to nitrite and nitric oxide within the digestive system of humans. Nitric oxide exerts potent vasodilator effects, which have been shown to reduce blood pressure and enhance exercise economy in humans. This pressure reducing effect may have implications within the regulation of blood flow during dynamic exercise in older adults.

Official Title
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Nitric Oxide Bioavailability and Dynamics of Blood Flow and Vasodilation With Age

Conditions
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Vasodilation, Blood Pressure, Active Hyperemia, Aging

Intervention / Treatment
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* Dietary Supplement: Super Beets
* Dietary Supplement: Beetroot powder


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Healthy older adults 60-80 years of age Exclusion Criteria: Hypertension, Smoking, Heart disease, Diabetes, Body mass index (BMI) ≥ 30 kg/m2, Autonomic disorders and other conditions that may alter blood pressure or vascular function Medications that might normally alter blood pressure or vascular function. Older women taking hormone replacement therapy medications.

Ages Eligible for Study
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Minimum Age: 60 Years
Maximum Age: 80 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Nitrate Rich Beetroot Powder (nitrate)<br>Dietary nitrate in the form of beetroot powder (10g) mixed in water will be administered acutely | Dietary Supplement: Super Beets<br>* Nitrate rich beetroot powder (10g) acutely<br>Dietary Supplement: Beetroot powder<br>* Nitrate devoid beetroot powder (10g) acutely<br>|
| Placebo Comparator: Placebo Beetroot Powder<br>Beetroot powder devoid of nitrate (10g) will be mixed in water and administered acutely | Dietary Supplement: Super Beets<br>* Nitrate rich beetroot powder (10g) acutely<br>Dietary Supplement: Beetroot powder<br>* Nitrate devoid beetroot powder (10g) acutely<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Skeletal Muscle Blood Flow within the Leg via Doppler Ultrasound | Leg blood flow via Doppler ultrasound examined during dynamic knee extension exercise. Change in blood flow in response to dynamic knee exercise will be measured to examine the influence of dietary nitrate. | Pre and 2 hours post acute ingestion of dietary nitrate and placebo with at least 5 days of separation between visits. | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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exercise hyperemia, vasodilation, nitric oxide, dietary nitrate