Factors That Influence Blood Vessel Regulation During Exercise in Humans

Not Applicable

Completed

• Conditions: Ischemic Preconditioning; Dietary Exposure
• Interventions: Dietary Supplement: High fat meal; Procedure: Ischemic preconditioning control; Procedure: Ischemic preconditioning; Dietary Supplement: Low fat meal

• Registration Number: NCT04887610
• Lead Sponsor: University of Guelph

Brief Summary

This study will examine two separate interventions: 1) the effects of ischemic preconditioning or 2) a high fat meal on the capacity of the brachial artery to overcome sympathetic activation and dilate during exercise (also known as functional sympatholysis). Participants will be asked to complete rhythmic handgrip exercise with and without the application of -20 mmHg lower body negative pressure to increase sympathetic activation. Doppler ultrasound will be used to continuously measure brachial artery blood flow. Participants will complete the handgrip exercise and lower body negative pressure before and after the applications of each interventions. Participants may elect to only complete one intervention rather than complete both protocols. Intervention one is active or control ischemic preconditioning. Intervention two is high or low fat meals.

Detailed Description

Not available

Study Timeline

• Study First Submitted: 2021-04-01
• Study First Submitted QC: 2021-05-10
• Study First Posted: 2021-05-14
• Study Start: 2021-05-20
• Primary Completion: 2022-11-15
• Study Completion: 2022-11-15
• Status Verified: 2023-03
• Last Update Submitted: 2023-03-27
• Last Update Posted: 2023-03-30

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 20

Inclusion Criteria

• 18 years or older
• Healthy

Exclusion Criteria

• History of smoking (tobacco or cannabis), defined as any smoking within the past 3 months
• Diagnosed cardiovascular or metabolic disease(s)
• Recent musculoskeletal injury handgrip exercise
• Prescription of chronic medications other than oral contraceptives
• History of hypertension or presence of arrhythmia

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: CROSSOVER

Arm && Interventions

Group	Intervention	Description
Low fat meal	High fat meal	-
Ischemic preconditioning control	Ischemic preconditioning control	-
Ischemic preconditioning	Ischemic preconditioning	-
High fat meal	Low fat meal	-

Primary Outcome Measures

Name	Time	Method
Forearm blood flow	3 hours after active and control interventions (Diet intervention only)	Doppler ultrasound - tested at rest and during rhythmic handgrip exercise with and without lower body negative pressure
Forearm vascular conductance	3 hours after active and control interventions (Diet intervention only)	Blood flow divided by blood pressure - tested at rest and during rhythmic handgrip exercise with and without lower body negative pressure

Secondary Outcome Measures

Name	Time	Method
Blood pressure	3 hours after active and control interventions (Diet intervention only)	Finger plethysmography - tested at rest and during rhythmic handgrip exercise with and without lower body negative pressure
Heart rate	3 hours after active and control interventions (Diet intervention only)	ECG - tested at rest and during rhythmic handgrip exercise with and without lower body negative pressure

Trial Locations

Locations (1)

University of Guelph - Human Cardiovascular Physiology Laboratory; 🇨🇦 Guelph, Ontario, Canada