Blood Flow Restriction

Blood Flow Restriction, commonly referred to as BFR, involves the application of a specialized tourniquet cuff to the proximal portion of an exercising arm or leg to reduce arterial inflow and restrict venous outflow into the limb. Exercising in this manner allows the use of low intensity exercise to elicit positive adaptations in muscle size, strength, or endurance typically associated with much heavier loads or higher intensities. The pressure applied with BFR should be personalized to the individual’s Limb Occlusion Pressure or LOP (You’ll see us refer to this as Personalized Blood Flow Restriction or PBFR). A range of pressure looks like it can be effective and different pressures may be required for the arm (40-50% of LOP) and for the leg (60-80% of LOP).  With BFR, resistance exercise with weight as light as 20-40% of an individual’s 1 repetition maximum can facilitate changes typically seen with lifting heavy weights, while endurance exercise can be prescribed for much shorter than typical durations and intensities less than 50% VO2max. 

The application of BFR has great potential to improve exercise prescription in a rehabilitation setting since it’s common to see patients that have exercise loading or intensity limitations due to injury, surgery, pain, or deconditioning. There may also be significant benefits in non-clinical populations with using BFR as a periodization tool or as a way to increase training frequency.

If you want to dive deeper into the available evidence on BFR, you can find some of the key papers on our Publications Page. You can also see a little more of our personal take on some of the BFR evidence or sub-topics by checking out our Blogs and Podcasts.

What patient populations can benefit from doing Blood Flow Restriction Training?

Almost any patient that is cleared to participate in exercise but can’t perform exercise at a high enough intensity to cause adaptation could benefit from Blood Flow Restriction Training. Nothing about BFR is diagnosis specific and its application could be as variable as traditional exercise. It can be used as a strategy to make available exercises stressful enough to induce an adaptive response.   

Is BFR Safe?

BFR has consistently demonstrated to be a safe modality in the literature. It has been performed on thousands of subjects in the peer-reviewed literature with little to no side effects.  

You can read some of the safety studies and review papers on our Publications Page

Is BFR within my scope of practice as a Physical Therapist or Athletic Trainer?

Physical therapists have an existing firm foundation in anatomy, physiology, therapeutic exercise, and the cardiorespiratory system, as well as clinical reasoning, which are the components of the safe application of blood flow restriction training.

Physical therapist education provides PTs with the requisite knowledge (muscular and vascular anatomy, and physiology and exercise physiology), as well as skills (therapeutic exercise prescription, monitoring of physiological vital signs and blood flow) to perform and monitor this type of therapeutic exercise. BFRT is part of the professional scope of practice for physical therapists.

Link to APTA: What to Know About Blood Flow Restriction Training

Similarly, the Board of Certification put out some information through an Approved Provider update on whether Athletic Trainers are appropriate to perform BFR. “ATs are healthcare professionals and fall under the scope of clinicians qualified to learn and perform BFR.” They also went on to say “Advanced continuing education through the Board of Certification is currently utilized to ensure ATs are taught the efficacy and safety of BFR and proper medical tourniquet applications.”

Is Education required prior to using BFR in a clinic setting?

There are no strict requirements around education prior to using BFR in a clinical setting. Since BFR fits within the scope of practice of PTs and ATs, it's up to the clinician to decide whether they're competent in implementing BFR. The additional guidance from APTA is that "each PT should consider his or her personal scope of practice before engaging in BFRT."

If you’d like to attend a course to enhance your understanding of BFR and how to apply it, you can find a list of our available Personalized BFR courses on the course page.

Why choose Delfi when there are cheaper options? 

We commonly get asked about how the Delfi device compares to others in the market.

  • Delfi has a proven track record of medical device manufacturing over the last 30 years making industry-standard surgical grade tourniquets.

  • Delfi has a proven track record of innovation and quality in the area of tourniquet design and manufacturing.

  • Delfi revolutionized tourniquet systems in 1980 with the invention of the microprocessor.

  • The Delfi microprocessor is credited with markedly reducing the incidence of nerve injury from surgical tourniquet application.

  • The Delfi PTS possesses patented limb occlusion pressure (LOP) detection technology.

  • The accuracy of Delfi's LOP technology has been researched and validated against a trained doppler ultrasound technician. (

  • The Delfi system has research validation demonstrating it applies consistent pressure throughout the exercise (

 The Delfi PTS for BFR is the most objective and safe way to perform and personalize BFR. Ultimately it is the responsibility of the clinician to decide what device to use for BFR. We prefer the objectivity of the Delfi device as it ensures a uniform application regardless of individual patient characteristics. Additionally, this objectivity allows a clinician to substantiate their choice in a BFR device.

 The Delfi PTS for BFR is the trusted BFR system used by the Department of Defense, the largest healthcare systems, US Olympic teams and professional and collegiate sports. In fact, the Delfi PTS for BFR is the only BFR device available on professional sports workers compensation in every league.

If you’d like to calculate the number of patient visits needed to pay off a device or the ROI on a device, you can visit the ROI calculator page on our website. 

 For more information on Delfi and the Delfi PTS, including certificates of use, visit:

Who can purchase a Delfi PTS for BFR System from you? 

At this time, only licensed medical healthcare providers that have completed an Owens Recovery Science, INC PBFR certification training may purchase a Delfi PTS for PBFR system. This includes the following providers: Medical Doctors, Physical Therapists, Athletic Trainers, Chiropractors and Occupational Therapists.

If you’ve already gone through our course and would like to purchase Delfi, follow this link to our Purchase Page!