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Trial registered on ANZCTR


Registration number
ACTRN12624000046505p
Ethics application status
Submitted, not yet approved
Date submitted
28/11/2023
Date registered
18/01/2024
Date last updated
18/01/2024
Date data sharing statement initially provided
18/01/2024
Type of registration
Prospectively registered

Titles & IDs
Public title
The effect of blood flow restriction exercise on pain perception
Scientific title
The effect of blood flow restriction exercise on pain modulation in individuals with and without pain
Secondary ID [1] 311046 0
Nil known
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Acute musculoskeletal pain 332164 0
Chronic pain 332165 0
Condition category
Condition code
Musculoskeletal 328882 328882 0 0
Normal musculoskeletal and cartilage development and function
Physical Medicine / Rehabilitation 328883 328883 0 0
Physiotherapy

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
The study will utilise a repeated measures design, with subjects performing a single acute resistance exercise session under two different conditions. The interventions will differ based on the application of blood flow restriction (BFR), and the volume of resistance exercise being performed. Restrictive cuffs will be fitted to the upper thighs of the participants, which will be inflated to 60% of their individual arterial occlusion pressure. In the low dose trial (LOW), participants will perform 4 x 10 repetitions with 30% of their one-repetition maximum in the barbell back squat. In the high dose trial (HIGH), participants will perform 4 sets consisting of 30, 15, 15, 15 repetitions, respectively, with 30% of their one-repetition maximum in the barbell back squat. All trials will consist of a single session to evaluate the acute effect of pain modulation, as assessed through pain pressure thresholds. Each trial will be roughly 45 minutes in duration and will occur face-to-face at La Trobe University in Melbourne, Australia. Each exercise session will be completed in a randomised order, and there will be a minimum of 72 hours and maximum of 10 days between trials. As this project involves apparently healthy individuals, the sessions for all interventions will be supervised, in a one-on-one format, by an accredited exercise scientist. However, a physiotherapist is involved in the project to advise on collection of pain pressure thresholds. The level of intensity for interventions involving resistance exercise will be prescribed using % of one-repetition maximum, with 30% being selected. Perceived effort will also be monitored during all interventions involving exercise using modified Borg RPE (0-10) and repetitions in reserve (RIR), to estimate proximity to failure. It is anticipated that the level of intensity will be vigorous in the high dose trial, moderate in the low dose trial, and low in the passive trial. Individual arterial occlusion pressure will be determined via doppler ultrasound. The restrictive cuff will be positioned around the proximal thigh and gradually and incrementally inflated until blood flow is no longer detected in the posterior tibial artery. Participants must complete all experimental visits to be included in the study. Adherence will be monitored directly as all sessions will be supervised.
Intervention code [1] 327494 0
Rehabilitation
Comparator / control treatment
Participants will perform two additional trials as comparator / control treatments. In the passive trial (PAS), participants will not perform any exercise and the cuffs will be inflated and delated for 3 x 5 min cycles. Therefore, the PAS condition will serve as a control treatment, as this will investigate the effects of blood flow restriction alone (without exercise) In the control trial (CON) participants will perform the low dose trial but without BFR cuffs, and therefore will explore the effects of exercise alone, without blood flow restriction. As this project involves apparently healthy individuals, all sessions will be supervised, in a one-on-one format, by an accredited exercise scientist. However, a physiotherapist is involved in the project to advise on collection of pain pressure thresholds. The level of intensity for resistance exercise in CON will again be prescribed using % of one-repetition maximum, with 30% being selected. Perceived effort will also be monitored during exercise using modified Borg RPE (0-10) and repetitions in reserve (RIR), to estimate proximity to failure. It is anticipated that the level of intensity will be moderate in the CON trials, and low in the PAS trial. Individual arterial occlusion pressure will be determined via doppler ultrasound. The restrictive cuff will be positioned around the proximal thigh and gradually and incrementally inflated until blood flow is no longer detected in the posterior tibial artery. Participants must complete all experimental visits to be included in the study. Adherence will be monitored directly as all sessions will be supervised.
Control group
Active

Outcomes
Primary outcome [1] 336694 0
Pain perception
Timepoint [1] 336694 0
Pre-exercise (approximately 10 minutes before each exercise trial) and 3 minutes following cessation of each exercise trial.
Secondary outcome [1] 429345 0
Neuromuscular performance
Timepoint [1] 429345 0
Pre-exercise (approximately 5 minutes before each exercise trial) and 5 minutes following cessation of each exercise trial.

Eligibility
Key inclusion criteria
-History of strength training (minimum two years)
-Currently experiencing knee pain for >2 weeks. Knee pain may include any of the following conditions:
o Patellofemoral pain
o Post-operative ACL reconstruction surgery
o Meniscal injury
o Patellar tendinopathy
o Osteochondral defects
-Reporting pain in at least 1 of 3 following functional tests:
o Single leg squat
o Step down test
o Single leg hop
Minimum age
18 Years
Maximum age
40 Years
Sex
Both males and females
Can healthy volunteers participate?
Yes
Key exclusion criteria
-History of cardiovascular, vascular, or endothelial conditions
-Pregnancy
-Individuals with acute pain that dissipates <2 weeks
-Severe musculoskeletal injury that would limit the performance of exercise

Study design
Purpose of the study
Treatment
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Central randomisation by computer
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Simple randomisation using a randomisation table created by computer software (i.e. computerised sequence generation)
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
Actual
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
Actual
Sample size
Target
Accrual to date
Final
Recruitment in Australia
Recruitment state(s)
VIC

Funding & Sponsors
Funding source category [1] 315304 0
University
Name [1] 315304 0
La Trobe University
Country [1] 315304 0
Australia
Primary sponsor type
University
Name
La Trobe University
Address
Plenty Rd & Kingsbury Drive, Bundoora, VIC 3086
Country
Australia
Secondary sponsor category [1] 317355 0
None
Name [1] 317355 0
Address [1] 317355 0
Country [1] 317355 0

Ethics approval
Ethics application status
Submitted, not yet approved
Ethics committee name [1] 314228 0
Human Research Ethics Committee, La Trobe University
Ethics committee address [1] 314228 0
Ethics committee country [1] 314228 0
Australia
Date submitted for ethics approval [1] 314228 0
12/09/2023
Approval date [1] 314228 0
Ethics approval number [1] 314228 0

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

Contacts
Principal investigator
Name 130862 0
Dr Charlie Davids
Address 130862 0
La Trobe Sports Stadium, La Trobe University, Plenty Rd & Kingsbury Dr, VIC 3086
Country 130862 0
Australia
Phone 130862 0
+61 0413 541 974
Fax 130862 0
Email 130862 0
Contact person for public queries
Name 130863 0
Charlie Davids
Address 130863 0
La Trobe Sports Stadium, La Trobe University, Plenty Rd & Kingsbury Dr, VIC 3086
Country 130863 0
Australia
Phone 130863 0
+61 0413 541 974
Fax 130863 0
Email 130863 0
Contact person for scientific queries
Name 130864 0
Charlie Davids
Address 130864 0
La Trobe Sports Stadium, La Trobe University, Plenty Rd & Kingsbury Dr, VIC 3086
Country 130864 0
Australia
Phone 130864 0
+61 0413 541 974
Fax 130864 0
Email 130864 0

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
Yes
What data in particular will be shared?
Deidentified data relating to the study aim (pain perceptions, physical performance data etc.) will be made available upon reasonable request.
When will data be available (start and end dates)?
Data will be made available following publication of the associated manuscript, which is estimated in early 2025. There is no end date for data availability.
Available to whom?
Deidentified data will be made available on a case-by-case basis at the discretion of Primary Sponsor.
Available for what types of analyses?
Data will be made available for the purpose of meta-analyses, or any other purpose that is deemed appropriate by the primary sponsor.
How or where can data be obtained?
Data will be shared to the requesting party through a protected platform. Access to the data will be possible by requesting this via email to the principal investigator ([email protected]).


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.