The Effects of Lower Extremity Blood Flow Restriction Training on Power, and Muscle Size.
Trial Snapshot
- Phase
- Not Applicable
- Status
- Completed
- Enrollment
- 20
- Locations
- 1
- Primary Endpoint
- Change in Muscle Size after 4 weeks
Study Overview
Brief Summary
Blood-flow restriction training (BFR) is a technique utilized to provide the benefits of high intensity exercise (strength, power, hypertrophy) when applied to exercise intensities that are insufficient to produce these benefits without BFR. The technique involves the application of an occlusive cuff (similar in design to a blood pressure cuff) over the limb of an individual that is set to occlude arterial blood flow at a given percentage during exercise. BFR has demonstrated increased strength and muscle hypertrophy compared to control interventions in various populations including: healthy subjects, athletes, post-surgery, clinical rehabilitation, and older adults.
Most research on BFR has been conducted on single joint exercises and not exercises that exhibit more complex movements typically associated with daily activities. The early evidence of complex exercises combined with BFR suggests that strength and hypertrophy both improve, however more research needs to be conducted.
The purpose of this project is to determine if four weeks of BFR training combined with approach rowing and deadlifts increases strength, power, aerobic capacity, and muscle size. These results will be compared to an isovolumetric control.
Detailed Description
INITIAL DATA COLLECTION (60-75 minutes) Measurements will be performed by a researcher blinded to group allocation. Height and weight will be measured with a stadiometer and calibrated scale.
Participant will sit to complete the following intake forms: Par-Q+, Numeric Pain Rating Scale, International Physical Activity Questionnaire- short form After sitting at least 5 minutes the following resting measures will be taken: resting heart rate, resting blood pressure
Thigh Circumference (supine): Markings will be made bilaterally at the lateral femoral condyle, proximal greater trochanter, and a line in an anterior to posterior direction 50% between these two landmarks. A circumferential measurement of the thigh will be taken three separate times at that 50% line for each leg.
Muscle Size: Measurements will be taken of the vastus lateralis and biceps femoris following the protocol established by Ruas et al using the GE LOGIC e, GE Healthcare, WI, USA). Superficial markings will be made to assist the researcher in locating desired anatomical location for measurement. Markings will be made bilaterally at the lateral femoral condyle, proximal aspect of greater trochanter, and a line in an anterior to posterior direction 50% between these two landmarks. Participants will lay supine for vastus lateralis and prone for biceps femoris measurement. The ultrasound transducer will be placed on the skin, utilizing a water-gel coupling agent, oriented perpendicular to the skin interface over the muscle of interest at the line that marks 50% of the distance between lateral femoral condyle and proximal greater trochanter. Images will be saved in the ultrasound device using participant identifier, muscle visualized, and date (example: BFR01_VL_05.01.19). Images will be exported to a computer for analysis using ImageJ software (National Institutes of Health, Bethesda, MD, USA).
Maximal Vo2: Oxygen consumption will be assessed on stationary rower (Concept2 Inc., Morrisville, VT) utilizing a metabolic cart and gas exchange (ParvoMedics, Provo, UT). Throughout the exercise test rating of perceived exertion (RPE) will be assessed within the final 10 seconds of each stage. Each participant will proceed throughout the various stages of the exercise test in a sequential fashion until test is terminated for one of the following reasons (1) participant requests to stop exercise test, (2) RPE reaches 10 out of 10, (3) participant fails to maintain desired Watts for that stage.
Study Design
- Study Type
- Interventional
- Allocation
- Randomized
- Intervention Model
- Parallel
- Primary Purpose
- Treatment
- Masking
- Single (Outcomes Assessor)
Masking Description
Blinded researcher will perform preliminary and outcomes measures.
Eligibility Criteria
- Ages
- 18 Years to 60 Years (Adult)
- Sex
- All
- Accepts Healthy Volunteers
- Yes
Inclusion Criteria
- •Recreationally active adults (3 mo more days of moderate intensity physical activity per week, with at least some combination of aerobic and strength training).
Exclusion Criteria
- •Failure to achieve clearance for exercise participation via the Par-Q+ screening tool
- •Currently pregnant or with 3 months post-partum
- •Presence of chronic low back pain
- •history of surgery to change the structure of joints within the lower extremity (joint replacement, osteotomy)
- •Known blood clotting disorder or taking blood thinner medications
- •Presence of peripheral vascular disease
- •Presence of systemic or widespread pain disorder (fibromyalgia, chronic regional pain syndrome)
- •Currently under activity limitations for any reason
Arms & Interventions
Control Exercise Group
Participants allocated to the Control Exercise Group will participate in 8 total exercise sessions (2x per week for 4 weeks). Exercise sessions will include two exercise modalities 1)seated rowing ergometer and 2) dumbbell deadlifts. Exercise intensity will be individualized based upon preliminary testing with rowing at 80% maximal Watts, and deadlifts at 60% of one-repetition maximum.
Intervention: Seated Rowing Ergometer (Other)
Control Exercise Group
Participants allocated to the Control Exercise Group will participate in 8 total exercise sessions (2x per week for 4 weeks). Exercise sessions will include two exercise modalities 1)seated rowing ergometer and 2) dumbbell deadlifts. Exercise intensity will be individualized based upon preliminary testing with rowing at 80% maximal Watts, and deadlifts at 60% of one-repetition maximum.
Intervention: Deadlift (Other)
Blood Flow Restriction and Exercise Group
Participants allocated to the Control Exercise Group will participate in 8 total exercise sessions (2x per week for 4 weeks). Exercise sessions will include the application of blood flow restriction during two exercise modalities 1)seated rowing ergometer and 2) dumbbell deadlifts. Exercise intensity will be individualized based upon preliminary testing with rowing at 40% maximal Watts, and deadlifts at 30% of one-repetition maximum. Blow flow restriction will be applied at 80% occlusion during both exercise modalities.
Intervention: Seated Rowing Ergometer (Other)
Blood Flow Restriction and Exercise Group
Participants allocated to the Control Exercise Group will participate in 8 total exercise sessions (2x per week for 4 weeks). Exercise sessions will include the application of blood flow restriction during two exercise modalities 1)seated rowing ergometer and 2) dumbbell deadlifts. Exercise intensity will be individualized based upon preliminary testing with rowing at 40% maximal Watts, and deadlifts at 30% of one-repetition maximum. Blow flow restriction will be applied at 80% occlusion during both exercise modalities.
Intervention: Deadlift (Other)
Blood Flow Restriction and Exercise Group
Participants allocated to the Control Exercise Group will participate in 8 total exercise sessions (2x per week for 4 weeks). Exercise sessions will include the application of blood flow restriction during two exercise modalities 1)seated rowing ergometer and 2) dumbbell deadlifts. Exercise intensity will be individualized based upon preliminary testing with rowing at 40% maximal Watts, and deadlifts at 30% of one-repetition maximum. Blow flow restriction will be applied at 80% occlusion during both exercise modalities.
Intervention: Blood flow restriction (Other)
Outcomes
Primary Outcomes
Change in Muscle Size after 4 weeks
Time Frame: after 4 weeks of intervention
Cross-sectional measurement of muscle girth
Secondary Outcomes
- Change in Maximal Deadlift Strength after 4 weeks(after 4 weeks of intervention)
- Change in Maximal Oxygen Consumption after 4 weeks(after 4 weeks of intervention)
Investigators
Bradley Myers
Assistant Professor
Campbell University, Incorporated