by Jason Schexnayder, PT, DPT, CMTPT
What is Blood Flow Restriction Training?
According to our governing body in the physical therapy world, the American Physical Therapy Association (APTA) states that…
“Blood Flow Restriction Training uses the application of external pressure over the extremities. The applied pressure is sufficient enough to maintain arterial inflow while occluding venous outflow distal to the occlusion site. The goal is to enable patients to make greater strength gains while lifting lighter loads, thereby reducing the overall stress placed on the limb.”
Basically, Blood Flow Restriction Training (BFRT) allows you to use lighter weights without placing the same amount of stress on the body that you would with heavy resistance or high-intensity training.
How is it Performed?
Limb Occlusion Pressure (LOP)
- The best way to use BFRT is by determining your limb occlusion pressure (LOP) first. LOP is the minimal amount of pressure it takes to partially occlude your arterial blood flow. The LOP is different for each person and each limb. The best way to do this is through the use of a Doppler Ultrasound. Depending on the unit, you can manually use a Doppler Ultrasound to determine LOP. Other units have built-in Doppler Ultrasounds to constantly monitor pressure.
- An occlusion of 50% is typically used when treating the upper extremity. 80% occlusion is typically used when treating the lower extremity. Venous blood flow (veins) is completely occluded (100%) regardless of which limb your treating. Arterial blood flow (arteries) is occluded to a specified percentage (50% – 80%), though this can be changed manually. The percentage you use will also depend on the patient’s response to the applied pressure as well as the position their in while performing an exercise. You want to use the lowest pressure possible that is comfortable for the patient but also that creates the appropriate metabolic response to get the benefit you seek.
- The pressure is either maintained at the specified percentage throughout the entire treatment or it’s constantly monitored and changed during the exercise based on your changing pressure. Either way, this allows for a smaller percentage of oxygenated blood to enter the limb while deoxygenated blood remains in the limb. Because of this, blood builds-up or “pools” in the limb, and the muscles have less oxygenated blood to use for the exercise being performed.
Is it Safe?
Well, that depends. There are many ways to restrict blood flow to an extremity while exercising. However, not all of them are safe. IN FACT, if you occlude blood flow the wrong way you could cause more harm than good.
For instance, some people use elastic bands, belts, etc. in order to restrict blood flow. This is an example of UNSAFE BFRT as you won’t know if you’re using the correct amount of pressure. Too little pressure and it’s a waste of time. Too much pressure and you could potentially cause muscle breakdown, nerve damage, or worse.
There are some BFRT products out there that include a handheld Doppler Ultrasound with their BFRT cuffs, like Smart Cuffs. It’s a good product overall but using a handheld Doppler Ultrasound will involve human error and the cuffs don’t constantly monitor limb pressure during an exercise. A “fixed” pressure isn’t as effective since limb pressure constantly changes during an exercise.
To our knowledge, the best BFRT unit on the market is the Delfi BFR unit by Owens Recovery Science (picture above on the left). This unit has a built-in Doppler Ultrasound, wide tourniquet’s that improve comfortability, standardized protocols for the best treatment, safety shut-offs, and constant pressure monitoring. It’s FDA-listed as a medical tourniquet and is, therefore, one of the safest, if not the safest, unit on the market. FORTUNATELY, these are the units we use at Bourgeois PT.
Why does it Work?
Metabolite Theory is one way the research shows BFRT works…and here’s how…we’ll try to keep it simple…
Restricting blood flow decreases the amount of oxygen that can be used for an exercise. As a result, blood & fluid accumulates or “pools” in the restricted extremity. This “pooling” causes a build-up of metabolites and forces the body to switch from working in an aerobic state to an anaerobic state. This anaerobic work causes you to fatigue and as a result, your muscles begin to recruit more (and typically larger) muscle from the lack of oxygen. This tricks your body into thinking it’s performing high-intensity or heavy-load training.
Scientifically speaking, BFRT causes the following metabolite changes to occur:
- Increase In:
- Decrease In:
- Myostatin (reduces the bodies ability to grow muscle)
These cellular changes lead to an increase in strength and muscle growth (muscle hypertrophy) among other things. BFRT causes muscle growth (hypertrophy) consistently despite the mechanism of muscle growth due to BFRT not being completely understood yet.
BFRT is also believed to work because of Cell Swelling. However, this hasn’t been completely proven yet and for these reasons, we won’t cover it in this blog.
So what are the benefits of BFRT?
Again, it depends. Using good equipment, using it correctly, in the right situation, with the right settings and parameters, etc. all impact the results seen with BFRT. However, research does tell us what the potential benefits are of using BFRT…
- Increase In:
- Muscle Strength
- Hypertrophy (Muscle Growth/Size)
- Fast-Twitch Muscle Recruitment (due to the ↓ Oxygen and ↑ Lactic Acid )
- VO² Max (Endurance)
According to some research, BFRT also improves tendon and muscle structure showing that it has a protective effect on soft-tissues.
To BFRT or Not to BFRT?!?
BFRT certainly has its place in both the rehabilitation and training worlds. Post-surgical, acutely injured, de-conditioned, or other patients who can’t tolerate heavier loading seem to benefit most from BFRT. This doesn’t mean other populations don’t benefit from using BFRT. These are just the populations we see get the most benefit from BFRT. Below is a list of some of the conditions we commonly use BFRT for…
- Post-Surgical ACL and/or Meniscus Repairs
- Rotator Cuff Repairs (there’s more than one rotator cuff muscle, so ask you doctor which one he’s fixing!!!)
- Achilles Tendonopathy
- Patellofemoral Pain Syndrome (common in adolescents)
- Lateral Epicondylitis (AKA: Tennis Elbow) and Medial Epicondylitis (AKA: Golfers or Throwers Elbow)
- Hamstring Strains
BFRT allows these patients to use no load or low loads and still get similar benefits to heavy-resistance training. This is important because many of these patients lose or have quickly lost muscle size and strength due to their conditions. The ability to mimic heavy-resistance training with BFRT while minimizing the mechanical stress placed on the body helps to prevent or even reverse muscle loss and strength deficits. Doing this allows a patient to progress in their rehabilitation process more quickly. Once they’re capable of lifting heavier loads then they can transition towards this type of training. Research shows that BFRT is a good modality to supplement a heavy-resistance training program. Therefore, BFRT should be considered as a part of your programming even when transitioning to a heavy-resistance training program.
Still not convinced…
Then take a look at this video by Owens Recovery Science, which includes what Dwight Howard did with his training.
Also, Alex Smith, who suffered what’s supposed to be a “career-ending” injury, has used BFRT in his recovery. BFRT, along with proper rehab and training, has allowed Alex to return to playing in the NFL again…that’s amazing!!! (watch the documentary on his injury…it’s truly awesome!!!)
Can I only use BFRT if I’m receiving therapy services?!?!
Ohhh Heck NO!!!
As we just stated above, BFRT can help to supplement your regular exercise program. We can offer BFRT as a cash-service to anyone interested in using it to their benefit.
For example, after a day of heavy lifting or high-intensity exercise, you could use BFRT the following day while performing an endurance activity like walking. If you’re involved in a properly programmed training cycle then you should have what they call “de-load” weeks and this could be a great time to use BFRT. Maybe you’re in the middle of a sports season and need to maintain your strength and endurance without adding excess physical stress to the body, then BFRT is a good option. Or if you’re older, have a serious medical condition, or struggle to lift heavier weights in general but want to get similar benefits to lifting that way, then look no further than BFRT.
Contact us if you’re interested in using BFRT as a cash-based service. If you’d like more information or research articles pertaining to BFRT you can contact us for that as well.
(225) 744 – 4878