Evaluation of Sports Supplements on Blood Flow

NCT04278053 | Completed

• 1 other identifier: 1812163576
• Study Type: interventional
• Target: 24
• Locations: 1 country
• Sites: 1

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.

Conditions

Determine the Effects of Nitrosigine and Citrulline-malate on Flow-mediated Dilation Among Young Adults

Keywords

flow-mediated dilation; vasodilation; Nitrosigine; Citrulline-Malate

Outcome Measures

Primary Outcomes (1)

• Vasodilation

  Amount of brachial vasodilation caused by supplementation as measured by flow-mediated dilation and ultrasound

  60 minutes

Study Arms (3)

Nitrosigine supplementation

EXPERIMENTAL

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

Citrulline-Malate supplementation

EXPERIMENTAL

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

Placebo

PLACEBO COMPARATOR

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

Interventions

inositol-stabilized arginine silicate DIETARY_SUPPLEMENT

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.

Citrulline-Malate supplementation; Nitrosigine supplementation; Placebo

Eligibility Criteria

• Age: 18 Years - 29 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Healthy, regularly exercising young adults

You may not qualify if:

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

Sponsors & Collaborators

• University of Arkansas, Fayetteville: lead

Study Sites (1)

University of Arkansas

Fayetteville, Arkansas, 72701, United States

Location

MeSH Terms

Conditions

Aneurysm

Interventions

nitrosigine

Condition Hierarchy (Ancestors)

Vascular Diseases; Cardiovascular Diseases

Study Officials

• Michelle Gray, Ph.D

  University of Arkansas

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, INVESTIGATOR
• Masking Details: Both the participants and the researchers were blinded to the supplements until all data collection had been completed.
• Purpose: OTHER
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Associate Professor - Exercise Science

Model Details: Randomized, double-blind, crossover design

Study Record Dates

• First Submitted: February 18, 2020
• First Posted: February 20, 2020
• Study Start: October 15, 2018
• Primary Completion: May 8, 2019
• Study Completion: May 8, 2019
• Last Updated: May 24, 2022

Record last verified: 2022-05

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)