Try the modernized ClinicalTrials.gov beta website. Learn more about the modernization effort.
Working…
ClinicalTrials.gov
ClinicalTrials.gov Menu

Evaluation of Sports Supplements on Blood Flow

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details.
 
ClinicalTrials.gov Identifier: NCT04278053
Recruitment Status : Completed
First Posted : February 20, 2020
Last Update Posted : May 24, 2022
Sponsor:
Information provided by (Responsible Party):
Michelle Gray, University of Arkansas, Fayetteville

Brief Summary:
Many athletes seek to increase their plasma (blood) nitric oxide content prior to exercise in order to augment vasodilation. Increased vasodilation during exercise, especially high intensity resistance training, allows for more blood flow to muscle tissues, which may give the athlete benefits such as increased work capacity and acute muscle hyperemia, which is commonly referred to as muscle pump. Pre-workout supplements are typically taken 30 minutes to 1 hour prior to the onset of exercise, so the current investigation seeks to determine if citrulline malate or nitrosigine can effect vasodilation within 1 hour of supplementation, and if so, which supplement is more effective. Based on previous findings, we hypothesize that a certain exercise intensity needs to be present for citrulline malate and nitrosigine to have an effect, so a change may not be observable at rest.

Condition or disease Intervention/treatment Phase
Determine the Effects of Nitrosigine and Citrulline-malate on Flow-mediated Dilation Among Young Adults Dietary Supplement: inositol-stabilized arginine silicate Not Applicable

Detailed Description:
Data collection will be conducted by qualified research staff and students at the University of Arkansas Exercise Science Research Center (ESRC). Upon contact with the research team, a medical/health questionnaire will be sent via email to the subject. This will be the initial screening tool to determine if the subject qualifies for the project. The subjects must meet the inclusion and none of the exclusion criteria in order to qualify for the study. Participants will be instructed to do the following the day of data collection: 1. No caffeine, stimulants, or blood thinners (such as ibuprofen, advil, aspirin, warfarin, clopidogrel, etc.) 24 hours prior to testing. 2. Wear comfortable clothes (short sleeve top). 3. Take all medication as normal (aside from those mentioned in #1). Participant testing will be conducted as follows: participant arrives at ESRC; height, weight, blood pressure, and complete questionnaires (electronically): medical history, 24-hour dietary recall, International Physical Activity Questionnaire (IPAQ). IPAQ is a standardized questionnaire used to evaluate an individual's level of physical activity in their daily life. After completing all surveys, the subject will be asked to lie in a supine position for 15 minutes, then they will have the diameter of the brachial artery (medial side of upper arm) assessed with ultrasound (GE Logiq e). Ultrasound is a non-invasive way of determining the diameter of arteries. A total of 10 measurements will be taken of the brachial artery. After the initial 10 measurements (~3-5 minutes), flow-mediated dilation (FMD) will be performed. Flow mediated dilation will be performed with a Hokanson rapid cuff inflator. The cuff (blood pressure cuff) will be position on the forearm (just above the wrist) and will be inflated to 250-300mmHg for a period of 5 minutes to restrict blood flow. After the 5-minute inflation period, the cuff will deflate and vessel diameter will be re-assessed (10 additional trails). Following the initial FMD assessment, one of three supplements will be consumed: citrulline-malate (8 g), Nitrosigine (1.5 g), or placebo (8 g Dextrose). After consumption, participants will remain in ESRC for 60 minutes to allow for digestion of the substance. Following the 60-minute absorption period, FMD will be re-assessed.

Layout table for study information
Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 24 participants
Allocation: Randomized
Intervention Model: Crossover Assignment
Intervention Model Description: Randomized, double-blind, crossover design
Masking: Double (Participant, Investigator)
Masking Description: Both the participants and the researchers were blinded to the supplements until all data collection had been completed.
Primary Purpose: Other
Official Title: Effects of Nitrosigine on Flow-Mediated Dilation Among Young Adults
Actual Study Start Date : October 15, 2018
Actual Primary Completion Date : May 8, 2019
Actual Study Completion Date : May 8, 2019

Resource links provided by the National Library of Medicine

Drug Information available for: Inositol

Arm Intervention/treatment
Experimental: Nitrosigine supplementation
Ultrasound is a non-invasive way of determining the diameter of arteries. A total of 10 measurements will be taken of the brachial artery. After the initial 10 measurements (~3-5 minutes), flow-mediated dilation (FMD) was performed. Flow mediated dilation was performed with a Hokanson rapid cuff inflator. The cuff (blood pressure cuff) was position on the forearm (just above the wrist) and was inflated to 250-300mmHg for a period of 5 minutes to restrict blood flow. After the 5-minute inflation period, the cuff was deflated and vessel diameter was re-assessed (10 additional trails). Following the initial FMD assessment, Nitrosigine (1.5 g) was provided in an 8 ounce solution with a cherry flavoring to mask taste. After consumption, participants remained in ESRC for 60 minutes to allow for digestion of the substance. Following the 60-minute absorption period, FMD was re-assessed.
Dietary Supplement: inositol-stabilized arginine silicate
Participants were asked to complete the experimental protocol in a 2-hour fasted state. Each participant's brachial artery FMD was assessed twice during each trial, once before supplement ingestion, and again 60 minutes post-ingestion. Male participants were required to wait for a minimum of seven days between trials as a supplement washout period. Female participants reported for supplement trials outside of their follicular phase of the menstrual cycle so that results were not confounded by changes in serum estradiol, which can significantly attenuate flow-mediated dilation. Sixty minutes after supplement consumption, each participant was asked which supplement they thought they had consumed. Participants were also asked whether they experienced any adverse side effects.

Experimental: Citrulline-Malate supplementation
Ultrasound is a non-invasive way of determining the diameter of arteries. A total of 10 measurements will be taken of the brachial artery. After the initial 10 measurements (~3-5 minutes), flow-mediated dilation (FMD) was performed. Flow mediated dilation was performed with a Hokanson rapid cuff inflator. The cuff (blood pressure cuff) was position on the forearm (just above the wrist) and was inflated to 250-300mmHg for a period of 5 minutes to restrict blood flow. After the 5-minute inflation period, the cuff was deflated and vessel diameter was re-assessed (10 additional trails). Following the initial FMD assessment, Citrulline-Malate (8 g) was provided in an 8 ounce solution with a cherry flavoring to mask taste. After consumption, participants remained in ESRC for 60 minutes to allow for digestion of the substance. Following the 60-minute absorption period, FMD was re-assessed.
Dietary Supplement: inositol-stabilized arginine silicate
Participants were asked to complete the experimental protocol in a 2-hour fasted state. Each participant's brachial artery FMD was assessed twice during each trial, once before supplement ingestion, and again 60 minutes post-ingestion. Male participants were required to wait for a minimum of seven days between trials as a supplement washout period. Female participants reported for supplement trials outside of their follicular phase of the menstrual cycle so that results were not confounded by changes in serum estradiol, which can significantly attenuate flow-mediated dilation. Sixty minutes after supplement consumption, each participant was asked which supplement they thought they had consumed. Participants were also asked whether they experienced any adverse side effects.

Placebo Comparator: Placebo
Ultrasound is a non-invasive way of determining the diameter of arteries. A total of 10 measurements will be taken of the brachial artery. After the initial 10 measurements (~3-5 minutes), flow-mediated dilation (FMD) was performed. Flow mediated dilation was performed with a Hokanson rapid cuff inflator. The cuff (blood pressure cuff) was position on the forearm (just above the wrist) and was inflated to 250-300mmHg for a period of 5 minutes to restrict blood flow. After the 5-minute inflation period, the cuff was deflated and vessel diameter was re-assessed (10 additional trails). Following the initial FMD assessment, dextrose (8 g) was provided in an 8 ounce solution with a cherry flavoring to mask taste. After consumption, participants remained in ESRC for 60 minutes to allow for digestion of the substance. Following the 60-minute absorption period, FMD was re-assessed.
Dietary Supplement: inositol-stabilized arginine silicate
Participants were asked to complete the experimental protocol in a 2-hour fasted state. Each participant's brachial artery FMD was assessed twice during each trial, once before supplement ingestion, and again 60 minutes post-ingestion. Male participants were required to wait for a minimum of seven days between trials as a supplement washout period. Female participants reported for supplement trials outside of their follicular phase of the menstrual cycle so that results were not confounded by changes in serum estradiol, which can significantly attenuate flow-mediated dilation. Sixty minutes after supplement consumption, each participant was asked which supplement they thought they had consumed. Participants were also asked whether they experienced any adverse side effects.




Primary Outcome Measures :
  1. Vasodilation [ Time Frame: 60 minutes ]
    Amount of brachial vasodilation caused by supplementation as measured by flow-mediated dilation and ultrasound



Information from the National Library of Medicine

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.


Layout table for eligibility information
Ages Eligible for Study:   18 Years to 29 Years   (Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes
Criteria

Inclusion Criteria:

  • Healthy, regularly exercising young adults

Exclusion Criteria:

  • hypertension, metabolic disorders, previous consumption of pre-workout supplements 6 months prior to study, prescriptions medications known to effect the vasodilatory response.

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT04278053


Locations
Layout table for location information
United States, Arkansas
University of Arkansas
Fayetteville, Arkansas, United States, 72701
Sponsors and Collaborators
University of Arkansas, Fayetteville
Investigators
Layout table for investigator information
Principal Investigator: Michelle Gray, Ph.D University of Arkansas
Layout table for additonal information
Responsible Party: Michelle Gray, Associate Professor - Exercise Science, University of Arkansas, Fayetteville
ClinicalTrials.gov Identifier: NCT04278053    
Other Study ID Numbers: 1812163576
First Posted: February 20, 2020    Key Record Dates
Last Update Posted: May 24, 2022
Last Verified: May 2022
Individual Participant Data (IPD) Sharing Statement:
Plan to Share IPD: No

Layout table for additional information
Studies a U.S. FDA-regulated Drug Product: No
Studies a U.S. FDA-regulated Device Product: No
Keywords provided by Michelle Gray, University of Arkansas, Fayetteville:
flow-mediated dilation
vasodilation
Nitrosigine
Citrulline-Malate
Additional relevant MeSH terms:
Layout table for MeSH terms
Dilatation, Pathologic
Pathological Conditions, Anatomical
Inositol
Vitamin B Complex
Vitamins
Micronutrients
Physiological Effects of Drugs