Blood Flow Restriction and Low-Intensity Resistance Training
Conditions
Brief summary
The primary purposes of the proposed study is 1) To examine the changes of muscle fiber cross-sectional areas in the leg extensor muscles (vastus lateralis) pre- to post- 6 weeks of high-intensity resistance training and low-intensity resistance training with blood flow restriction and 2) To examine changes in motor unit size (a non-invasive measure of muscle fiber size) in the leg extensor muscles (vastus lateralis) pre- to post- 6 weeks of high-intensity resistance training and low-intensity resistance training with blood flow restriction.
Detailed description
Specific Aims and Hypotheses: Specific Aim 1: To examine the changes of type I and II (different types of muscle fibers) muscle fiber cross-sectional areas in the leg extensor muscles (vastus lateralis) pre- to post- 6 weeks of high-intensity resistance training and low-intensity resistance training with blood flow restriction. Hypothesis 1: Type I and II fiber cross-sectional area will increase following low-intensity resistance training with blood flow restriction, however, only cross-sectional area of type II fibers will increase post high-intensity resistance training. Specific Aim 2: To examine changes in the size of the motor units that are active during low and high intensity contractions in the leg extensor muscles (vastus lateralis) pre- to post- 6 weeks of high-intensity resistance training and low-intensity resistance training with blood flow restriction. Hypothesis 2: The motor units that are active during low and high intensity contractions will increase in size from low-intensity resistance training with blood flow restriction, but only the motor units that are active during high intensity contractions will increase in size from high-intensity resistance training. Specific Aim 3: To examine changes in whole muscle cross-sectional area as measured via ultrasound pre- to post- 6 weeks of high-intensity resistance training and low-intensity resistance training with blood flow restriction. Hypothesis 3: Whole muscle cross-sectional area will increase to similar degrees from both high-intensity resistance training and low-intensity resistance training with blood flow restriction.
Interventions
DEVICEBlood Flow Restriction Cuffs
This intervention consists of inflatable cuffs that are designed to partially occlude veinous blood return from the lower extremities during resistance training.
This intervention consists of performing low-intensity bilateral (both legs at the same time) leg extensions using 30% of a participants 1 repetition maximum (the maximum weight an individual can complete 1 repetition with, but not 2) to volitional failure.
This intervention consists of performing high-intensity bilateral (both legs at the same time) leg extensions using 80% of a participants 1 repetition maximum (the maximum weight an individual can complete 1 repetition with, but not 2) to volitional failure.
Sponsors
University of Kansas
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
BASIC_SCIENCE
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to 30 Years
Healthy volunteers
Yes
Inclusion criteria
\-
Exclusion criteria
* Participants must not have participated in resistance training more than 5 times in the 6 months preceding the study. * Participants must be healthy and free of any cardiovascular, metabolic or musculoskeletal conditions that may affect the results of the investigation. * Participants must not have a history of severe hip, knee and/or ankle injuries, or any other pathological conditions that impair their motor control. * Participants must not have any pre-existing cardiovascular conditions that involve blood flow/blood clotting. * Participants who are currently taking blood thinners or any medications regulating blood pressures or heart rate will not be eligible to participate in the study. * Female participants who are pregnant at the start of or who are planning to become pregnant during the resistance training intervention will not be eligible to participate in the study.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Determine changes in muscle fiber cross-sectional area | July 2021-May 2022 | A primary purpose of the study is to examine the changes of muscle fiber cross-sectional areas in the leg extensor muscles (vastus lateralis) pre- to post- 6 weeks of high-intensity resistance training and low-intensity resistance training with blood flow restriction |
| Determine changes in motor unit size | July 2021- May 2022 | Another primary purpose of the study is to examine changes in motor unit size (a non-invasive measure of muscle fiber size) in the leg extensor muscles (vastus lateralis) pre- to post- 6 weeks of high-intensity resistance training and low-intensity resistance training with blood flow restriction |
Countries
United States
Outcome results
None listed