The Science of BFR Training

It’s common for experienced exercisers to utilize novel — and, to outsiders, strange-looking — tools to increase the challenge and get more value out of their typical workouts. Endurance athletes, for instance, may use altitude masks to limit airflow and potentially improve performance variables such as VO2 max and power output. And recently, blood flow restriction devices have increased in popularity.

Also known as occlusion training or BFR training, blood flow restriction training involves exercising with a tourniquet (commonly used in research settings) or an elastic band (often used in commercial settings) wrapped around your arm or leg to reduce blood flow in and out of the area, says Matt Delany, the Director of Programming and Innovation at Equinox.

In reducing circulation, blood flow restriction training is meant to drive a build-up of metabolites (such as lactate and diprotonated phosphate) and reduce oxygen supply to the working muscle, leading to muscular fatigue and increased motor unit recruitment, explains Delany. “All of this allows an individual to work at a lower load and intensity while still achieving similar benefits [as high-intensity training],” he notes.

But is blood flow restriction actually a worthwhile fitness tactic? Here’s what science says.