BFR and Muscle Mitochondrial Oxidative Capacity

Hypertrophy Clinical Trial

Official title:

Impact of Low-Intensity Resistance Exercise With and Without Blood Flow Redistricted (BFR) on Muscle Mitochondrial Oxidative Capacity

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT03723226
• Other study ID #: IRB#3934
• Status: Completed
• Phase: N/A
• Start date: January 28, 2019
• Est. completion date: July 1, 2023

Study information

• Verified date: August 2023
• Source: Louisiana State University and A&M College
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

Blood flow restricted (BFR) exercise has been shown to improve skeletal muscle adaptations to resistance exercise. BFR uses blood pressure cuffs (i.e., tourniquets) to reduce skeletal muscle blood flow during resistance exercise. One benefit of BFR is that skeletal muscle adaptations to resistance exercise training including muscle hypertrophy and increases in strength can be achieved at lower-loads (e.g., 25-30% 1RM), that are often comparable to more traditional resistance training loads (70-85% 1RM). However, the impact that low-load BFR resistance exercise has on muscle quality and bioenergetics is unknown. The present study will examine the impact of 6 weeks of low-load, single-leg resistance exercise training with or without personalized BFR on measures of muscle mass, strength, quality, and mitochondrial bioenergetics. The investigators will recruit and study up to 30, previously sedentary, healthy, college-aged adults (18-40 years). The investigators will measure muscle mass using Dual Energy X-Ray Absorptiometry and muscle strength and endurance using isokinetic testing. The investigators will normalize knee extensor strength to lower limb lean mass to quantify muscle quality. The investigators will also use near infrared spectroscopy (NIRS) to measure mitochondrial oxidative capacity in the vastus lateralis. Finally, the investigators will measure markers of systemic inflammation and markers of muscle damage using commercially available ELISA assays.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 24
• Est. completion date: July 1, 2023
• Est. primary completion date: July 1, 2023
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: All
• Age group: 18 Years to 40 Years

Eligibility

Inclusion Criteria.

1. Capable and willing to give written informed consent

2. Capable of understanding inclusion and exclusion criteria

3. 18-40 years of age inclusive

4. Body Mass Index (BMI) between 18.5-30 kg/m2 inclusive

5. No medical condition that would limit their participation in supervised exercise training based on the Physical Activity Readiness Questionnaire for Everyone (PARQ+)

6. No current prescription medications, with the exception of birth control

7. Willing to allow researchers to use data, biospecimens (e.g., blood) and images (e.g., Dual Energy x-Ray Absorptiometry) for research purposes after study participation is completed

Exclusion Criteria.

1. Evidence or self-report being pregnant, lactating, or anticipating becoming pregnant in the next year

2. Participation in resistance or aerobic exercise training > 2 days per week within the 3 months prior to screening

3. Self-report of history of type 1 or 2 diabetes mellitus

4. Self-report history of cardiovascular, peripheral vascular, cerebral vascular, pulmonary, or renal disease

5. Self-report or evidence of uncontrolled hypertension

6. Self-report history of blood clotting disorders

7. Self-report history of deep vein thrombosis or pulmonary embolism

8. Self-report history of sickle cell trait

9. Self-report history of varicose veins

10. Self-report history of a myopathy leading to muscle loss, weakness, severe cramps or myalgia

11. Self-report history of orthopedic limitations that would preclude them from participation in a dynamic exercise program

12. Self-report history of musculoskeletal disorders (e.g., severe osteoarthritis, rheumatoid arthritis, avascular necrosis or osteonecrosis)

13. Self-report history of neurological disorders (e.g., peripheral neuropathy, amyotrophic lateral sclerosis, multiple sclerosis, fibromyalgia, Parkinson's disease)

14. Weight loss of > 10% in the last 3 months prior to screening

15. Active smoking

16. Current consumption of > 14 alcoholic drinks per week based on self-report

17. Absolute Contraindication to Exercise as Defined by the American College of Sports Medicine,1 including:

1. Resting diastolic blood pressure > 100 mm Hg

2. Resting systolic blood pressure > 180 mm Hg

3. Resting heart rate > 100 beats per min

18. Self-report acute viral or bacterial upper or lower respiratory infection at screening

19. Any other condition that in the judgement of the Principal Investigator and/or the Medical Director of this protocol may interfere with study participation and adherence to the protocol

Related Conditions & MeSH terms

• Hypertrophy
• Mitochondria
• Strength

Intervention

Behavioral:
• Low Load Resistance Exercise
Subjects allocated to Low Load Resistance Exercise will undergo 6 weeks of single-legged low load (25%) resistance exercise. Subjects will then perform 4 sets of 30, 15, 15 and 15 repetitions at 25% of their 1RM for the single-legged leg press and single-legged knee extensions. Their contralateral leg will serve as within subject control.
• Low Load Resistance Exercise + BFR
Subjects allocated to Low Load Resistance Exercise + BFR will undergo 6 weeks of single-legged low load (25%) resistance exercise with blood flow restriction (60% occlusion pressure). Subjects will then perform 4 sets of 30, 15, 15 and 15 repetitions at 25% of their 1RM for the single-legged leg press and single-legged knee extensions. Their contralateral leg will serve as within subject control.

Locations

Country	Name	City	State
United States	Lousiana State University	Baton Rouge	Louisiana

Sponsors (2)

Lead Sponsor	Collaborator
Louisiana State University and A&M College	Delfi, Inc.

Country where clinical trial is conducted

United States, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Changes in Mitochondrial Oxidative Capacity	Changes in mitochondrial oxidative capacity will be measured using near infrared spectroscopy (NIRS).	Changes from baseline (pre-training) to follow-up (about 48-72 hours post-training).
Secondary	Changes in Muscle Mass measured by Dual Energy X-ray Absorptiometry	Changes in muscle mass will be measured by Dual Energy X-ray Absorptiometry	Changes from baseline (pre-training) to follow-up (about 48-72 hours post-training)
Secondary	Changes in Muscle Strength measured using Isokinetic Dynamometry	Changes in muscle strength measured using isokinetic dynamometry	Changes from baseline (pre-training) to follow-up (about 48-72 hours post-training)
Secondary	Changes in Muscle Endurance measured using Isokinetic Dynamometry	Changes in muscle endurance measured using isokinetic dynamometry	Changes from baseline (pre-training) to follow-up (about 48-72 hours post-training)