Trial Review

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Trial registered on ANZCTR


Registration number
ACTRN12624001430527
Ethics application status
Approved
Date submitted
11/10/2024
Date registered
6/12/2024
Date last updated
6/12/2024
Date data sharing statement initially provided
6/12/2024
Type of registration
Prospectively registered

Titles & IDs
Public title
Blood Flow Restriction Pressure and its Impact on Electromyographic Activation
Scientific title
Study of Blood Flow Restriction Pressure and its Impact on Electromyographic Activation in Healthy Subjects CrossFit Practitioners
Secondary ID [1] 313166 0
Nil known
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Electromyographic activation 335452 0
blood flow restriction 335622 0
Condition category
Condition code
Physical Medicine / Rehabilitation 332010 332010 0 0
Physiotherapy

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Study Overview: This study aims to assess muscle activation during CrossFit exercises using electromyography (EMG) to measure the electrical activity of muscles. EMG is a diagnostic technique that involves placing electrodes on the skin to record the electrical signals generated during muscle contraction. This method allows us to observe and analyze muscle activation in real time, providing crucial insights into how blood flow restriction (BFR) impacts muscle function during exercise.

By using EMG, we will evaluate muscle activation in selected upper and lower limb exercises. This will enable us to determine whether the application of BFR, as per the proposed formula, increases muscle activation, as suggested in the physical training literature. The EMG data collected will allow us to compare muscle activity with and without BFR, contributing to a robust scientific understanding of how this technique could be applied more effectively and safely in both athletic training and physical rehabilitation contexts. The duration of the intervention will be 30 minutes, which will be administered by a physiotherapist.

Electromyography (EMG) Protocol:

General Preparation:

1.1 Skin Preparation:
Prior to electrode placement, the skin will be cleaned, dried, and shaved if necessary, to ensure optimal adhesion and electrical conductivity of the electrodes.

1.2 Electrode Placement:
Electrodes will be placed on the muscle belly of each target muscle, following established guidelines for EMG electrode positioning to ensure accuracy and consistency in data collection. The specific placement sites are as follows:

Quadriceps (Vastus Medialis and Vastus Lateralis): Electrodes will be positioned on the mid-portion of each muscle.
Gluteus Maximus: Electrodes will be placed over the thickest part of the muscle, avoiding the upper adipose layer.
Hamstrings: Electrodes will be placed on the mid-posterior thigh.
Spinal Erectors: Electrodes will be aligned along the lumbar spine, at the level of L3.
Pectoralis Major: Electrodes will be positioned on the mid-clavicular line, approximately 5 cm below the clavicle.
Triceps Brachii: Electrodes will be placed in the mid-portion of the muscle.
Deltoid (Lateral Head): Electrodes will be placed on the middle third of the deltoid, along the lateral aspect of the shoulder.
Triceps (Bench Press): The same placement as described for the triceps in the mid-arm position.
1.3 Calculation of Maximum Voluntary Isometric Contraction (MVIC):
Prior to the exercise sessions, participants will perform a series of maximum voluntary isometric contractions for each muscle group to be assessed. This will serve as the reference value for subsequent EMG data normalization.

1.4 Normalization of EMG Data:
The EMG signals recorded during the exercise sessions will be normalized as a percentage of the EMG signal obtained during the MVIC test. This allows for meaningful comparisons of muscle activation across different exercises, sessions, and participants, accounting for individual variations in muscle strength.

EMG Data Recording:

EMG data will be collected in real-time during the execution of exercises using mdurance EMG equipment. Each participant will perform 4 sets of 30-15-15-15 repetitions of each exercise at 20-30% of their one-repetition maximum (1RM), with BFR cuffs that will be used to restrict blood flow. The amount of pressure applied will be 80% of the pressure needed for maximal arterial occlusion (which will be previously determined). There will be a 30" rest between sets (without BFR).

Lower Limb Exercises:

Squat: EMG data will be recorded from the quadriceps and gluteus maximus.
Deadlift: EMG data will be recorded from the hamstrings and spinal erectors.

Upper Limb Exercises:

Bench Press: EMG data will be recorded from the pectoralis major and triceps brachii.
Military Press: EMG data will be recorded from the deltoids and triceps brachii.

Additional information: there will be no need to assess adherence to the intervention because it is a very short intervention consisting of one session.
Intervention code [1] 329740 0
Treatment: Other
Comparator / control treatment
The outcomes will be assessed when performing the exercises with BFR (intervention group), and without BFR (control group). The control group will perform the exercises at an intensity of 70% RM (4 sets of 12 RM).

The order in which they will carry out one or another intervention will be randomized using the random function of Microsoft Excel. The wash-out period will be 3 days.
Control group
Active

Outcomes
Primary outcome [1] 339613 0
Blood lactate (mmol/L)
Timepoint [1] 339613 0
Baseline and immediate post- training (post 4 sets of each exercise)
Secondary outcome [1] 440590 0
Fatigue perceived
Timepoint [1] 440590 0
Baseline and immediate post-training (post 4 sets of each exercise)
Secondary outcome [2] 440591 0
Explosive force during the four exercises (squat, dead lift, military press, bench press)
Timepoint [2] 440591 0
Baseline and immediate post- training (post 4 sets of each exercise)
Secondary outcome [3] 440592 0
Muscle pain
Timepoint [3] 440592 0
Baseline and immediate post- training (post 4 sets of each exercise)
Secondary outcome [4] 440593 0
Muscle oxygen saturation
Timepoint [4] 440593 0
Baseline and immediate post-training (post 4 sets of each exercise)
Secondary outcome [5] 440594 0
Muscle activation (EMG) during squat
Timepoint [5] 440594 0
Baseline and immediate post-training (post 4 sets of each exercise)
Secondary outcome [6] 441208 0
Muscle activation (EMG) during dead lift
Timepoint [6] 441208 0
Baseline and immediate post-training (post 4 sets of each exercise)
Secondary outcome [7] 441211 0
Muscle activation (EMG) during military press
Timepoint [7] 441211 0
Baseline and immediate post-training (post 4 sets of each exercise)
Secondary outcome [8] 441212 0
Muscle activation (EMG) during bench press
Timepoint [8] 441212 0
Baseline and immediate post-training (post 4 sets of each exercise)

Eligibility
Key inclusion criteria
Active subjects with a regular practice of CrossFit for at least 6 months.
Minimum age
18 Years
Maximum age
40 Years
Sex
Both males and females
Can healthy volunteers participate?
Yes
Key exclusion criteria
Muscle injuries in the last 6 months
Chirurgical processes in the last year
Metabolic diseases
Medication
Vascular problems
Pregnancy

Study design
Purpose of the study
Educational / counselling / training
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
central randomisation by phone/fax/computer
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Simple randomisation using a randomisation table from a statistic book
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?



Intervention assignment
Crossover
Other design features
Phase
Not Applicable
Type of endpoint/s
Efficacy
Statistical methods / analysis

Recruitment
Recruitment status
Not yet recruiting
Date of first participant enrolment
Anticipated
6/01/2025
Actual
Date of last participant enrolment
Anticipated
28/02/2025
Actual
Date of last data collection
Anticipated
28/02/2025
Actual
Sample size
Target
40
Accrual to date
Final
Recruitment outside Australia
Country [1] 26629 0
Spain
State/province [1] 26629 0

Funding & Sponsors
Funding source category [1] 317608 0
Self funded/Unfunded
Name [1] 317608 0
Country [1] 317608 0
Primary sponsor type
Individual
Name
María García-Arrabe (Universidad Europea de Madrid, SPAIN)
Address
Country
Spain
Secondary sponsor category [1] 319918 0
Individual
Name [1] 319918 0
Guillermo García-Pérez-de-Sevilla (Universidad Europea de Madrid, SPAIN)
Address [1] 319918 0
Country [1] 319918 0
Spain

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 316313 0
Comité de Ética de la Investigación de la Universidad Rey Juan Carlos
Ethics committee address [1] 316313 0
Ethics committee country [1] 316313 0
Spain
Date submitted for ethics approval [1] 316313 0
01/04/2024
Approval date [1] 316313 0
02/07/2024
Ethics approval number [1] 316313 0
280520243442024

Summary
Brief summary
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 137490 0
Dr María García-Arrabe
Address 137490 0
Universidad Europea de Madrid. Calle Tajo s/n 28670 Villaviciosa de Odón (SPAIN)
Country 137490 0
Spain
Phone 137490 0
+34615346292
Fax 137490 0
Email 137490 0
[email protected]
Contact person for public queries
Name 137491 0
María García-Arrabe
Address 137491 0
Universidad Europea de Madrid. Calle Tajo s/n 28670 Villaviciosa de Odón (SPAIN)
Country 137491 0
Spain
Phone 137491 0
+34615346292
Fax 137491 0
Email 137491 0
[email protected]
Contact person for scientific queries
Name 137492 0
María García-Arrabe
Address 137492 0
Universidad Europea de Madrid. Calle Tajo s/n 28670 Villaviciosa de Odón (SPAIN)
Country 137492 0
Spain
Phone 137492 0
+34615346292
Fax 137492 0
Email 137492 0
[email protected]

Data sharing statement
Will the study consider sharing individual participant data?
No


What supporting documents are/will be available?

No Supporting Document Provided


Results publications and other study-related documents

Documents added manually
No documents have been uploaded by study researchers.

Documents added automatically
No additional documents have been identified.