Effects of a High-fat Meal on Exercise-mediated Sympatholysis

The goal of this trial is to examine the effects of a single high-fat meal with or without the co-ingestion of dietary nitrate on exercise-mediated sympatholysis. The main questions it aims to answer are:

1. What are the mechanisms responsible for reduced exercise-mediated sympatholysis following a high-fat meal
2. Can dietary nitrate prevent the declines in exercise-mediated sympatholysis

Participants will be asked to complete three study visits in a randomized order:

1. Low-fat meal
2. High-fat meal
3. High-fat meal plus dietary nitrate

Exercise-mediated sympatholysis will be measured using Doppler ultrasound via a protocol involving rhythmic handgrip exercise and a lower body negative pressure stimulus. Sympatholysis will be assessed before each meal, and at 1, 2, and 3 hours post-prandial.

Study Overview

• Status: Completed
• Conditions: Diet, Healthy
• Intervention / Treatment: Dietary supplement: Beetroot drink; Dietary supplement: Placebo; Dietary supplement: Control

• Study Type: Interventional
• Enrollment (Actual): 15
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Canada
  • Ontario
    • Guelph, Ontario, Canada, N1G2W1
      • University of Guelph - Human Cardiovascular Physiology Laboratory

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• 18-30 years of age
• Healthy, free of known cardiovascular, metabolic, or musculoskeletal disease

Exclusion Criteria:

• Diagnosed cardiovascular or metabolic disease, injury preventing handgrip exercise, prescription of chronic medications other than oral contraceptives.
• Inability to abstain from drugs (except oral contraceptives), caffeine, alcohol, strenuous physical activity, mouthwash, and multivitamins prior to study

Study Plan

How is the study designed?

Design Details

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

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: High-fat meal with Beetroot Drink; 2 sausage egg McMuffins and a hashbrown from McDonalds and 10g of beetroot powder mixed in 250 mL cold tap water drink	Dietary supplement: Beetroot drink; Drink containing 10g of beetroot powder in 250 mL cold tap water; Other Names: Superbeets
Placebo Comparator: High-fat meal with Placebo Drink; 2 sausage egg McMuffins and a hashbrown from McDonalds and Mio water flavouring in 250 mL cold tap water. Trace amounts of sugar and sodium were mixed to match the beetroot supplement	Dietary supplement: Placebo; Mio flavouring in 250 mL cold tap water. Trace amounts of sugar and sodium were added to match the content in the beetroot supplement; Other Names: Mio
Sham Comparator: Low-fat meal control; Kelloggs cornflakes (110g), greek yogurt (400g), skim milk (500 mL), and orange juice (250 mL). Energy-matched to the high-fat meal	Dietary supplement: Control; Low-fat meal with cornflakes, greek yogurt, skim milk, and orange juice

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Forearm vascular conductance	Duplex ultrasound of brachial artery	Before intervention and 1, 2, 3 hours post-intervention
Forearm blood flow	Duplex ultrasound of brachial artery	Before intervention and 1, 2, 3 hours post-intervention
Systolic and Diastolic Blood Pressure	finger plethysmography	Before intervention and 1, 2, 3 hours post-intervention

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Plasma levels of Norepinephrine	ELISA kit	Blood collected before intervention and 1, 2, 3 hours post-intervention. Blood frozen at -80 degrees Celsius and analyzed at later date
Plasma levels of Nitrate/Nitrite concentration	ELISA kit	Blood collected before intervention and 1, 2, 3 hours post-intervention. Blood frozen at -80 degrees Celsius and analyzed at later date
Blood Glucose concentrations	Blood glucose monitor	Blood collected before intervention and 1, 2, 3 hours post-intervention. Blood analyzed immediately after collection at each time point
Plasma levels of Triglycerides	Triglyceride assay kit	Blood collected before intervention and 1, 2, 3 hours post-intervention. Blood frozen at -80 degrees Celsius and analyzed at later date

Collaborators and Investigators

• Sponsor: University of Guelph
• Investigators: Principal Investigator: Philip Millar, PhD, University of Guelph

Study record dates

Study Major Dates

• Study Start (Actual): January 8, 2024
• Primary Completion (Actual): July 30, 2024
• Study Completion (Actual): July 30, 2024

Study Registration Dates

• First Submitted: December 15, 2023
• First Submitted That Met QC Criteria: December 15, 2023
• First Posted (Actual): December 29, 2023

Study Record Updates

• Last Update Posted (Actual): September 19, 2024
• Last Update Submitted That Met QC Criteria: September 16, 2024
• Last Verified: September 1, 2024

More Information

Terms related to this study

• Keywords: Exercise; Functional sympatholysis
• Other Study ID Numbers: 23-01-017

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No