The Effect of Short-term L-citrulline Supplementation on Blood Pressure and Arterial Stiffness

Study Overview
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Brief Summary
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The goal of this clinical trial is to examine the effect of short-term L-Citrulline on central and peripheral blood pressure in healthy older adults. The main questions it aims to answer are: Does L-citrulline favorably affect blood pressure at rest and during exercise? Does L-citrulline favorably affect arterial stiffness? Does L-citrulline favorably affect muscle oxygenation at rest and during exercise? Participants will be asked to consume L-citrulline and a placebo for six days and participate in the evaluation of their blood pressure, arterial stiffness, and muscle oxygenation before and after each intervention. Researchers will compare L-citrulline and placebo groups to examine whether L-citrulline supplementation affects the above health parameters.

Official Title
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The Effect of Short-term L-citrulline Supplementation on Blood Pressure and Arterial Stiffness

Conditions
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Blood Pressure

Intervention / Treatment
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* Dietary Supplement: L-Citrulline
* Dietary Supplement: Placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: subject provides written informed consent. normal health profile. Exclusion Criteria: history of musculoskeletal injury in the legs during the previous six months. smoker. consumption of any medication the last three months. consumption of any nutritional supplement the last three months.

Ages Eligible for Study
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Minimum Age: 55 Years
Maximum Age: 70 Years

Sexes Eligible for Study
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Male

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: Prevention
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: L-Citrulline<br>Participants will receive 6 g (3 g every 12 h) of L-citrulline (Now, L-citrulline Pure Powder) for six-days. | Dietary Supplement: L-Citrulline<br>* 6 g (3 g every 12 h) of L-citrulline for six days<br>|
| Placebo Comparator: Placebo<br>Participants will receive 6 g (3 g every 12 h) of maltodextrin (Now, Maltodextrin) for six-days. | Dietary Supplement: Placebo<br>* 6 g (3 g every 12 h) of maltodextrin for six days<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in aortic and brachial systolic blood pressure (rest) |  | Change from baseline aortic and brachial systolic blood pressure at 7 days. | 
| Change in aortic and brachial systolic blood pressure |  | Change from baseline aortic and brachial systolic blood pressure at the second minute of exercise. | 
| Change in carotid-femoral pulse wave velocity (cfPWV) (rest) |  | Change from baseline aortic and brachial systolic blood pressure at 7 days. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in pulse pressure (rest) |  | Change from baseline pulse pressure at 7 days. | 
| Change in heart rate (rest) |  | Change from baseline heart rate at 7 days. | 
| Change in augmented pressure (rest) |  | Change from baseline augmented pressure at 7 days. | 
| Change in augmentation index (rest) |  | Change from baseline augmentation index at 7 days. | 
| Change in forward and backward wave pressure (rest) |  | Change from baseline forward and backward wave pressure at 7 days. | 
| Change in muscle oxyhemoglobin (rest) |  | Change from baseline oxyhemoglobin at 7 days. | 
| Change in pulse pressure (exercise) |  | Change from baseline pulse pressure at the second minute of exercise. | 
| Change in heart rate (exercise) |  | Change from baseline heart rate at the second minute of exercise. | 
| Change in augmented pressure (exercise) |  | Change from baseline augmented pressure at the second minute of exercise. | 
| Change in augmentation index (exercise) | The ideal augmentation index is between 20 and 80. Values above 80 are considered high, and above 121 indicate high arterial stiffness. | Change from baseline augmentation index at the second minute of exercise. | 
| Change in forward and backward wave pressure (exercise) |  | Change from baseline forward and backward wave pressure at the second minute of exercise. | 
| Change in muscle deoxyhemoglobin (exercise) |  | Change from baseline muscle deoxyhemoglobin at the second minute of exercise. | 
| Change in muscle deoxyhemoglobin (rest) |  | Change from baseline muscle deoxyhemoglobin at 7 days. | 
| Change in muscle oxyhemoglobin (exercise) |  | Change from baseline muscle oxyhemoglobin at the second minute of exercise. | 
| Change in muscle oxyhemoglobin (rest) |  | Change from baseline muscle oxyhemoglobin at 7 days. |