Effect of NO Precursors on Physiological Responses to Exercise

Study Overview
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Brief Summary
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NO is an ubiquitous molecule contributing to many physiological functions such as vasodilation, immune and oxidative stress responses. NO production can be supplemented either by providing substrate to the NO-synthase (L-Arginine and L-Citruline) or by providing nitrate which can lead to NO. In the present project the investigators evaluate the effect of various acute and chronic oral NO precursors supplementation on exercise performance and responses in healthy young and older subjects.

Official Title
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The Effect of NO Precursors on Physiological Responses to Exercise

Conditions
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Physiology

Intervention / Treatment
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* Dietary Supplement: Nitrate
* Dietary Supplement: Nitrate and L-Arginine
* Dietary Supplement: Nitrate and L-Citrulline
* Dietary Supplement: Placebo
* Biological: Evaluation of post-ischemic vascular reactivity
* Biological: Neuromuscular evaluations


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Sedentary subjects No cardiovascular, respiratory, metabolic and neurological disorders Exclusion Criteria: Body mass index > 28 kg.m-2 Smoker Alcool intake > 10g/day Psychiatric diseases Subjects under treatment able to interfere with their cardiovascular, metabolic and neurological status

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 70 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: Parallel Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Acute intake<br>Evaluation after acute intake of the food supplement. | Dietary Supplement: Nitrate<br>* Subjects will be supplemented orally either acutely or chronically (4-8 weeks) with NO precursors.<br>Dietary Supplement: Nitrate and L-Arginine<br>* Subjects will be supplemented orally either acutely or chronically (4-8 weeks) with NO precursors.<br>Dietary Supplement: Nitrate and L-Citrulline<br>* Subjects will be supplemented orally either acutely or chronically (4-8 weeks) with NO precursors.<br>Dietary Supplement: Placebo<br>* Subjects will be supplemented orally either acutely or chronically (4-8 weeks) with a placebo.<br>Biological: Evaluation of post-ischemic vascular reactivity<br>* After the intake of the supplement. Concentration of hemoglobin (g/mL) in the quadriceps with the device : NIRS system Oxymon, ARTINIS.<br>Biological: Neuromuscular evaluations<br>* After the intake of the supplement. Measure the stretching force in the ankle (N)<br>|
| Active Comparator: Chronic intake<br>Evaluation before and after chronic intake of the food supplement. | Dietary Supplement: Nitrate and L-Citrulline<br>* Subjects will be supplemented orally either acutely or chronically (4-8 weeks) with NO precursors.<br>Dietary Supplement: Placebo<br>* Subjects will be supplemented orally either acutely or chronically (4-8 weeks) with a placebo.<br>Biological: Evaluation of post-ischemic vascular reactivity<br>* After the intake of the supplement. Concentration of hemoglobin (g/mL) in the quadriceps with the device : NIRS system Oxymon, ARTINIS.<br>Biological: Neuromuscular evaluations<br>* After the intake of the supplement. Measure the stretching force in the ankle (N)<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Neuromuscular evaluations | After the intake of the supplement. Measure the stretching force in the ankle (N) | 3 half days | 
| Evaluation of post-ischemic vascular reactivity | After the intake of the supplement. Concentration of hemoglobin (g/mL) in the quadriceps with the device : NIRS system Oxymon, ARTINIS. | 3 half days |