The 2 primary factors that impact pressure in BFR bands
When utilizing pneumatic blood flood restriction (BFR) training bands, it is important to understand how much air should be put into the band. Unfortunately, there isn’t always a clear, straight forward answer as the goal with BFR training should be to allow the artery to remain open. This degree of opening allows blood flow to continue to enter and exit the limb while exercising and reduces risk when executing BFR training.
Pressures used in the bands can vary greatly depending upon what type of BFR bands are being used. There are two factors that consistently impact the amount of pressure that should be put into the band.
The width of the BFR bands
It has been established, that the wider the BFR bands are the less pressure it will take to occlude the artery. Weatherholt published a study in 2019 comparing KAASTU bands (5 centimeters) with Delfi bands (11.5 centimeters) in determining how much pressure was required to cause occlusion of the artery under the band. The Delfi bands caused occlusion at around 240 mmHg and they were unable to cause occlusion with the KAASTU bands at its maximal pressure of 500 mmHg. This study in a way validated the design of KAASTU bands as they aren’t designed with the intention to occlude.
Wider BFR bands = less pressure to cause arterial occlusion.
Narrower BFR bands = more pressure to cause arterial occlusion.
When looking at BFR bands on the market it is very consistent that narrower bands will recommend higher pressures than wider ones. This is due to the ceiling for safe application (when it comes to causing occlusion) being elevated with narrower bands.
The material used for the BFR bands
The second factor is the material used in the design of the bands. If the BFR bands are rigid and less forgiving, it doesn’t take as much pressure to provide a productive stimulus. If the muscle contracts under the band, that also elevates the pressure more drastically than a flexible and more forgiving band.
B Strong makes very flexible BFR bands that also have multiple chambers. Due to both the width and flexibility you are going to see recommended pressures well above recommended pressures for most other BFR bands on the market. This is why B Strong can safely be applied with pressures well above one’s systolic blood pressure. The characteristics of these BFR bands are different than traditional blood pressure cuffs. Check out the video below for a short explainer.
In summary, wider, rigid bands will use less pressure than narrow, flexible ones to provide a similar stimulus. Both types of bands can work to produce positive outcomes when using BFR bands, but understanding these concepts will allow for better application of BFR training.