Exercise Training, Hemodynamic Response
Conditions
Keywords
blood flow restriction, blood pressure, yoga
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.
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.
Interventions
DEVICEHokanson 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.
DEVICEBStrong 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.
Sponsors
Savannah Wooten
Stray-Gundersen, Sten, Ph.D.
University of Texas at Austin
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
BASIC_SCIENCE
Masking
SINGLE (Subject)
Masking description
The participants will not know which condition they will receive on the day of testing.
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.
Eligibility
Sex/Gender
ALL
Age
18 Years to 40 Years
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
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| 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. |
| 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. |
Countries
United States
Participant flow
Pre-assignment details
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.
Participants by arm
| Arm | Count |
|---|---|
| Blood Flow Restriction Exercise 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. | 20 |
| Total | 20 |
Baseline characteristics
| Characteristic | Blood Flow Restriction Exercise | — |
|---|---|---|
| Age, Categorical <=18 years | 0 Participants | — |
| Age, Categorical >=65 years | 0 Participants | — |
| Age, Categorical Between 18 and 65 years | 20 Participants | — |
| Age, Continuous | 23 year STANDARD_DEVIATION 4 | — |
| Body weight | 71 kg STANDARD_DEVIATION 10 | — |
| Race and Ethnicity Not Collected | — | — Participants |
| Sex: Female, Male Female | 10 Participants | — |
| Sex: Female, Male Male | 10 Participants | — |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk | EG002 affected / at risk | EG003 affected / at risk | EG004 affected / at risk |
|---|---|---|---|---|---|
| deaths Total, all-cause mortality | 0 / 20 | 0 / 20 | 0 / 20 | 0 / 20 | 0 / 20 |
| other Total, other adverse events | 0 / 20 | 0 / 20 | 0 / 20 | 0 / 20 | 0 / 20 |
| serious Total, serious adverse events | 0 / 20 | 0 / 20 | 0 / 20 | 0 / 20 | 0 / 20 |
Outcome results
Primary
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.
Time frame: Before (baseline) and after the exercise interventions
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Exercise With Hokanson Cuffs | Flow-mediated Dilation | Baseline (before conditions) | 7.0 percentage of resting diameter | Standard Error 2 |
| Exercise With Hokanson Cuffs | Flow-mediated Dilation | After conditions | 6.8 percentage of resting diameter | Standard Error 1.8 |
| Exercise With BStrong Bands | Flow-mediated Dilation | After conditions | 7.1 percentage of resting diameter | Standard Error 2 |
| Exercise With BStrong Bands | Flow-mediated Dilation | Baseline (before conditions) | 7.2 percentage of resting diameter | Standard Error 2.2 |
| Exercise Without Inflated Bands/Cuffs | Flow-mediated Dilation | After conditions | 7.1 percentage of resting diameter | Standard Error 1.9 |
| Exercise Without Inflated Bands/Cuffs | Flow-mediated Dilation | Baseline (before conditions) | 7.0 percentage of resting diameter | Standard Error 1.8 |
| Yoga Poses With BStrong Bands Inflated | Flow-mediated Dilation | After conditions | 7.0 percentage of resting diameter | Standard Error 2 |
| Yoga Poses With BStrong Bands Inflated | Flow-mediated Dilation | Baseline (before conditions) | 6.8 percentage of resting diameter | Standard Error 1.6 |
| Yoga Poses With BStrong Bands Uninflated | Flow-mediated Dilation | After conditions | 6.7 percentage of resting diameter | Standard Error 1.7 |
| Yoga Poses With BStrong Bands Uninflated | Flow-mediated Dilation | Baseline (before conditions) | 6.9 percentage of resting diameter | Standard Error 2 |
Primary
Systolic Blood Pressure
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.
Population: Baseline (before Experimental Arm Participation) data are reported below.
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Exercise With Hokanson Cuffs | Systolic Blood Pressure | Baseline (before the experimental arm participation) | 116 mmHg | Standard Deviation 11 |
| Exercise With Hokanson Cuffs | Systolic Blood Pressure | Immediately after | 150 mmHg | Standard Deviation 16 |
| Exercise With BStrong Bands | Systolic Blood Pressure | Baseline (before the experimental arm participation) | 116 mmHg | Standard Deviation 9 |
| Exercise With BStrong Bands | Systolic Blood Pressure | Immediately after | 127 mmHg | Standard Deviation 10 |
| Exercise Without Inflated Bands/Cuffs | Systolic Blood Pressure | Baseline (before the experimental arm participation) | 117 mmHg | Standard Deviation 7 |
| Exercise Without Inflated Bands/Cuffs | Systolic Blood Pressure | Immediately after | 158 mmHg | Standard Deviation 14 |
| Yoga Poses With BStrong Bands Inflated | Systolic Blood Pressure | Immediately after | 160 mmHg | Standard Deviation 15 |
| Yoga Poses With BStrong Bands Inflated | Systolic Blood Pressure | Baseline (before the experimental arm participation) | 117 mmHg | Standard Deviation 7 |
| Yoga Poses With BStrong Bands Uninflated | Systolic Blood Pressure | Baseline (before the experimental arm participation) | 115 mmHg | Standard Deviation 8 |
| Yoga Poses With BStrong Bands Uninflated | Systolic Blood Pressure | Immediately after | 130 mmHg | Standard Deviation 15 |