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

• Sponsor: University of Texas at Austin (Other)
• Overall Status: Terminated
• CT.gov ID: NCT03540147
• Collaborator: Savannah Wooten (Other), Sten Stray-Gundersen (Other)
• Enrollment: 20
• Location: 1
• Arms: 5
• Actual Duration (Months): 15.9
• Patients Per Site Per Month: 1.3

Study Details

Study Description

Brief Summary

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.

Condition or Disease	Intervention/Treatment	Phase
Exercise Training; Hemodynamic Response	Device: Hokanson Cuffs; Device: BStrong Bands	N/A

Detailed Description

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.

Study Design

• Study Type: Interventional
• Actual Enrollment: 20 participants
• Allocation: Randomized
• Intervention Model: Crossover Assignment
• Intervention 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.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 (Participant)
• Masking Description: The participants will not know which condition they will receive on the day of testing.
• Primary Purpose: Basic Science
• Official Title: The Impact of Blood Flow Restriction (BFR) on Exercise and Hemodynamic Responses
• Actual Study Start Date: Jan 26, 2018
• Actual Primary Completion Date: May 26, 2019
• Actual Study Completion Date: May 26, 2019

Arms and Interventions

Arm	Intervention/Treatment
Experimental: Exercise with Hokanson cuffs Participants will walk on the treadmill with Hokanson cuffs inflated.	Device: Hokanson Cuffs; 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.
Experimental: Exercise with BStrong Bands Participants will walk on the treadmill with BStrong bands inflated.	Device: BStrong Bands; 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.
Sham Comparator: Exercise without inflated bands/cuffs Participants will walk on the treadmill with non-inflated BStrong bands.	Device: BStrong Bands; 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.
Experimental: Yoga poses with BStrong bands inflated Participants will perform 15-20 yoga poses with BStrong bands inflated.	Device: BStrong Bands; 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.
Sham Comparator: Yoga poses with BStrong bands uninflated Participants will perform 15-20 yoga poses with uninflated BStrong bands.	Device: BStrong Bands; 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.

Outcome Measures

Primary Outcome Measures

1. Systolic Blood Pressure [Measurements were taken at Baseline (before Experimental Arm Participation) and immediately after Experimental Arm Participation.]

   Arterial blood pressure was measured using the automatic oscillometric methods.

2. Flow-mediated Dilation [Before (baseline) and after the exercise interventions]

   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.

Eligibility Criteria

Criteria

• Ages Eligible for Study: 18 Years to 40 Years
• Sexes Eligible for Study: All
• Accepts Healthy Volunteers: Yes

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

Contacts and Locations

Locations

	Site	City	State	Country	Postal Code
1	Cardiovascular Aging Research Lab at UT Austin	Austin	Texas	United States	78712

Sponsors and Collaborators

• University of Texas at Austin
• Savannah Wooten
• Sten Stray-Gundersen

Investigators

• Principal Investigator: Hirofumi Tanaka, PhD, University of Texas at Austin

Study Documents (Full-Text)

• Study Protocol and Statistical Analysis Plan - Feb 7, 2019

More Information

Publications

• Hunter SD, Dhindsa MS, Cunningham E, Tarumi T, Alkatan M, Nualnim N, Tanaka H. Impact of Hot Yoga on Arterial Stiffness and Quality of Life in Normal and Overweight/Obese Adults. J Phys Act Health. 2016 Dec;13(12):1360-1363. doi: 10.1123/jpah.2016-0170. Epub 2016 Aug 24. Erratum in: J Phys Act Health. 2017 Jan;14 (1):76.
• Hunter SD, Dhindsa MS, Cunningham E, Tarumi T, Alkatan M, Nualnim N, Tanaka H. The effect of Bikram yoga on arterial stiffness in young and older adults. J Altern Complement Med. 2013 Dec;19(12):930-4. doi: 10.1089/acm.2012.0709. Epub 2013 Jun 5.
• Miles SC, Chun-Chung C, Hsin-Fu L, Hunter SD, Dhindsa M, Nualnim N, Tanaka H. Arterial blood pressure and cardiovascular responses to yoga practice. Altern Ther Health Med. 2013 Jan-Feb;19(1):38-45.
• Renzi CP, Tanaka H, Sugawara J. Effects of leg blood flow restriction during walking on cardiovascular function. Med Sci Sports Exerc. 2010 Apr;42(4):726-32. doi: 10.1249/MSS.0b013e3181bdb454.
• Shimizu R, Hotta K, Yamamoto S, Matsumoto T, Kamiya K, Kato M, Hamazaki N, Kamekawa D, Akiyama A, Kamada Y, Tanaka S, Masuda T. Low-intensity resistance training with blood flow restriction improves vascular endothelial function and peripheral blood circulation in healthy elderly people. Eur J Appl Physiol. 2016 Apr;116(4):749-57. doi: 10.1007/s00421-016-3328-8. Epub 2016 Jan 28.
• Sugawara J, Tomoto T, Tanaka H. Impact of leg blood flow restriction during walking on central arterial hemodynamics. Am J Physiol Regul Integr Comp Physiol. 2015 Oct;309(7):R732-9. doi: 10.1152/ajpregu.00095.2015. Epub 2015 Aug 5.

• Responsible Party: Hirofumi Tanaka, Professor, University of Texas at Austin
• ClinicalTrials.gov Identifier: NCT03540147
• Other Study ID Numbers: 2017-10-0074
• First Posted: May 30, 2018
• Last Update Posted: Mar 11, 2021
• Last Verified: Feb 1, 2021

• Individual Participant Data (IPD) Sharing Statement: Yes
• Plan to Share IPD: Yes
• Studies a U.S. FDA-regulated Drug Product: No
• Studies a U.S. FDA-regulated Device Product: Yes
• Keywords provided by Hirofumi Tanaka, Professor, University of Texas at Austin: blood flow restriction; blood pressure; yoga

Study Results

Participant Flow

Pre-assignment Detail	This is a cross-over study. Each subject performed all 5 experimental conditions that includes "exercise with Hokanson cuffs", "Exercise with BStrong bands", "Exercise without inflated bands/cuffs", "Yoga poses with BStrong bands inflated" and "Yoga poses with BStrong bands uninflated". The number of subjects studied is 20.

Arm/Group Title	Blood Flow Restriction Exercise
Arm/Group Description	This is a cross-over study. Each subject performed all 5 experimental conditions that includes "exercise with Hokanson cuffs", "Exercise with BStrong bands", "Exercise without inflated bands/cuffs", "Yoga poses with BStrong bands inflated" and "Yoga poses with BStrong bands uninflated".
Period Title: Overall Study
STARTED	20
COMPLETED	20
NOT COMPLETED	0

Baseline Characteristics

Arm/Group Title	Blood Flow Restriction Exercise
Arm/Group Description	Participants will walk on the treadmill with Hokanson cuffs inflated. Hokanson Cuffs: 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.
Overall Participants	20
Age (Count of Participants)
<=18 years	0 0%
Between 18 and 65 years	20 100%
>=65 years	0 0%
Age (year) [Mean (Standard Deviation) ]
Mean (Standard Deviation) [year]	23 (4)
Sex: Female, Male (Count of Participants)
Female	10 50%
Male	10 50%
Race and Ethnicity Not Collected (Count of Participants)
Body weight (kg) [Mean (Standard Deviation) ]
Mean (Standard Deviation) [kg]	71 (10)

Outcome Measures

1. Primary Outcome

Title	Systolic Blood Pressure
Description	Arterial blood pressure was measured using the automatic oscillometric methods.
Time Frame	Measurements were taken at Baseline (before Experimental Arm Participation) and immediately after Experimental Arm Participation.

Outcome Measure Data

Analysis Population Description

Baseline (before Experimental Arm Participation) data are reported below.

Arm/Group Title	Exercise With Hokanson Cuffs	Exercise With BStrong Bands	Exercise Without Inflated Bands/Cuffs	Yoga Poses With BStrong Bands Inflated	Yoga Poses With BStrong Bands Uninflated
Arm/Group Description	Participants will walk on the treadmill with Hokanson cuffs inflated. Hokanson Cuffs: 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.	Participants will walk on the treadmill with BStrong bands inflated. BStrong Bands: 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.	Participants will walk on the treadmill with non-inflated BStrong bands. BStrong Bands: 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.	Participants will perform 15-20 yoga poses with BStrong bands inflated. BStrong Bands: 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.	Participants will perform 15-20 yoga poses with uninflated BStrong bands. BStrong Bands: 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.
Measure Participants	20	20	20	20	20
Baseline (before the experimental arm participation)	116 (11)	116 (9)	117 (7)	117 (7)	115 (8)
Immediately after	150 (16)	127 (10)	158 (14)	160 (15)	130 (15)

2. Primary Outcome

Title	Flow-mediated Dilation
Description	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.
Time Frame	Before (baseline) and after the exercise interventions

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Exercise With Hokanson Cuffs	Exercise With BStrong Bands	Exercise Without Inflated Bands/Cuffs	Yoga Poses With BStrong Bands Inflated	Yoga Poses With BStrong Bands Uninflated
Arm/Group Description	Participants will walk on the treadmill with Hokanson cuffs inflated. Hokanson Cuffs: 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.	Participants will walk on the treadmill with BStrong bands inflated. BStrong Bands: 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.	Participants will walk on the treadmill with non-inflated BStrong bands. BStrong Bands: 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.	Participants will perform 15-20 yoga poses with BStrong bands inflated. BStrong Bands: 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.	Participants will perform 15-20 yoga poses with uninflated BStrong bands. BStrong Bands: 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.
Measure Participants	20	20	20	20	20
Baseline (before conditions)	7.0 (2)	7.2 (2.2)	7.0 (1.8)	6.8 (1.6)	6.9 (2)
After conditions	6.8 (1.8)	7.1 (2.0)	7.1 (1.9)	7.0 (2)	6.7 (1.7)

Adverse Events

Time Frame	Each participants came to the laboratory twice in the span of 2 weeks.
Arm/Group Title	Exercise With Hokanson Cuffs		Exercise With BStrong Bands		Exercise Without Inflated Bands/Cuffs		Yoga Poses With BStrong Bands Inflated		Yoga Poses With BStrong Bands Uninflated
Arm/Group Description	Participants will walk on the treadmill with Hokanson cuffs inflated. Hokanson Cuffs: 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.		Participants will walk on the treadmill with BStrong bands inflated. BStrong Bands: 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.		Participants will walk on the treadmill with non-inflated BStrong bands. BStrong Bands: 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.		Participants will perform 15-20 yoga poses with BStrong bands inflated. BStrong Bands: 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.		Participants will perform 15-20 yoga poses with uninflated BStrong bands. BStrong Bands: 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.
All Cause Mortality
	Exercise With Hokanson Cuffs		Exercise With BStrong Bands		Exercise Without Inflated Bands/Cuffs		Yoga Poses With BStrong Bands Inflated		Yoga Poses With BStrong Bands Uninflated
	Affected / at Risk (%)	# Events	Affected / at Risk (%)	# Events	Affected / at Risk (%)	# Events	Affected / at Risk (%)	# Events	Affected / at Risk (%)	# Events
Total	0/20 (0%)		0/20 (0%)		0/20 (0%)		0/20 (0%)		0/20 (0%)
Serious Adverse Events
	Exercise With Hokanson Cuffs		Exercise With BStrong Bands		Exercise Without Inflated Bands/Cuffs		Yoga Poses With BStrong Bands Inflated		Yoga Poses With BStrong Bands Uninflated
	Affected / at Risk (%)	# Events	Affected / at Risk (%)	# Events	Affected / at Risk (%)	# Events	Affected / at Risk (%)	# Events	Affected / at Risk (%)	# Events
Total	0/20 (0%)		0/20 (0%)		0/20 (0%)		0/20 (0%)		0/20 (0%)
Other (Not Including Serious) Adverse Events
	Exercise With Hokanson Cuffs		Exercise With BStrong Bands		Exercise Without Inflated Bands/Cuffs		Yoga Poses With BStrong Bands Inflated		Yoga Poses With BStrong Bands Uninflated
	Affected / at Risk (%)	# Events	Affected / at Risk (%)	# Events	Affected / at Risk (%)	# Events	Affected / at Risk (%)	# Events	Affected / at Risk (%)	# Events
Total	0/20 (0%)		0/20 (0%)		0/20 (0%)		0/20 (0%)		0/20 (0%)

Limitations/Caveats

[Not Specified]

More Information

Certain Agreements

All Principal Investigators ARE employed by the organization sponsoring the study.

There is NOT an agreement between Principal Investigators and the Sponsor (or its agents) that restricts the PI's rights to discuss or publish trial results after the trial is completed.