The Impact of Blood Flow Restriction (BFR) on Exercise and Hemodynamic Responses

Study Overview
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Brief Summary
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The impact of blood flow restriction (BFR) on exercise and hemodynamic responses will be studied. The use of BFR will be studied during yoga and low-intensity aerobic exercise in healthy subjects with no history of chronic illness ranging from 18-40 years of age. This study will evaluate several conditions related to cardiovascular physiology in order to determine the safety and efficacy of this type of exercise training. First, the effects of two distinct types of BFR cuffs (BStrong and Hokanson) will be studied during low-intensity aerobic exercise on vascular function. Second, the effect of yoga will be studied with and without the use of BStrong bands on vascular function. Outcome measures include acute effects on endothelial function i.e. flow-mediated dilation, arterial stiffness, beat-by-beat blood pressure, heart rate, RPE (rate of perceived exertion), and blood lactate. For this intervention, the BFR cuffs will be used during exercise to evaluate its safety and efficacy. Since BFR is becoming a widely popular method of exercise, it is important to study its safety and hemodynamic effects.

Detailed Description
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Participants will be tested a total of 5 times; twice for the yoga portion and thrice for the aerobic exercise (walking) portion. Outcome measures will be consistent across the five visits and will take approximately 2.5 hours to complete. The order of the five separate sessions will be randomized such that the participant cannot expect which condition they will be performing.

Official Title
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The Impact of Blood Flow Restriction (BFR) on Exercise and Hemodynamic Responses

Conditions
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Exercise Training, Hemodynamic Response

Intervention / Treatment
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* Device: Hokanson Cuffs
* Device: BStrong Bands


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Healthy adults Exclusion Criteria: Pregnancy A recent illness, recent surgery, or any medical intervention history of diabetes, heart disease, or other cardiovascular problems

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 40 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: Crossover Assignment
Interventional Model Description: Each participant will undergo five visits to the laboratory for repeated testing under five different conditions. The sessions will be randomized and will take 2.5 hours to complete.
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Exercise with Hokanson cuffs<br>Participants will walk on the treadmill with Hokanson cuffs inflated. | Device: Hokanson Cuffs<br>* Each subject will participate in all (5) experimental arms. The order in which the experimental arms will be completed will be randomly assigned to the participant.<br>|
| Experimental: Exercise with BStrong Bands<br>Participants will walk on the treadmill with BStrong bands inflated. | Device: BStrong Bands<br>* Each subject will participate in all (5) experimental arms. The order in which the experimental arms will completed will be randomly assigned to the participant.<br>|
| Sham Comparator: Exercise without inflated bands/cuffs<br>Participants will walk on the treadmill with non-inflated BStrong bands. | Device: BStrong Bands<br>* Each subject will participate in all (5) experimental arms. The order in which the experimental arms will completed will be randomly assigned to the participant.<br>|
| Experimental: Yoga poses with BStrong bands inflated<br>Participants will perform 15-20 yoga poses with BStrong bands inflated. | Device: BStrong Bands<br>* Each subject will participate in all (5) experimental arms. The order in which the experimental arms will completed will be randomly assigned to the participant.<br>|
| Sham Comparator: Yoga poses with BStrong bands uninflated<br>Participants will perform 15-20 yoga poses with uninflated BStrong bands. | Device: BStrong Bands<br>* Each subject will participate in all (5) experimental arms. The order in which the experimental arms will completed will be randomly assigned to the participant.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Systolic Blood Pressure | Arterial blood pressure was measured using the automatic oscillometric methods. | Measurements were taken at Baseline (before Experimental Arm Participation) and immediately after Experimental Arm Participation. | 
| Flow-mediated Dilation | After 20 minutes of supine rest, endothelial function was measured via flow-mediated dilation (FMD) technique by measuring the brachial artery's diameter increase following a brief period of occlusion using an automated diagnostic ultrasound system. A blood pressure cuff was placed on the forearm with the proximal edge of the cuff above with the participant's antecubital fossa. Two cross-sectional images of the artery were acquired utilizing the automated ultrasound probe proximal to the antecubital fossa. Following baseline metrics, the cuff was inflated to 50 mmHg above resting systolic blood pressure for 5 minutes to occlude blood flow. After 5 minutes of occlusion, the cuff was deflated, and both brachial artery diameter and blood flow velocity were measured simultaneously and continuously for two-minutes immediately post occlusion. FMD was calculated as a percent increase in brachial artery diameter at the post-blood flow occlusion compared with the pre-blood flow occlusion. | Before (baseline) and after the exercise interventions | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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blood flow restriction, blood pressure, yoga