Blood flow restriction: A potential new approach to rehabilitation?

31 December 2021

A recent review of the literature looked at 11 studies of BFR with close to 240 older adult participants. While muscular adaptations had been recognized in various populations, the evidence was scant in older adults. This review showed greater gains in muscle strength in those who participated in BFR compared to those in traditional training or walking programs.

While promising, more work needs to be done to help patients and providers determine the best training regimens. Currently there is no standard for BFR training, and different researchers and therapists use different cuff pressures, cuff sizes, and numbers of sets and repetitions. Training ranges in frequency from weekly to near-daily.

Post-operatively, patients who have undergone tendon repairs such as anterior cruciate ligament (ACL) reconstruction must wait for their tissues to heal before they start to work out. BFR training decreases this period because patients can start post-operative exercises and muscle strengthening activities earlier, with lighter weights.

Studies from the United States have started blood flow training as early as two days after surgery, although Stephen Patterson, an exercise physiologist at St. Mary’s University in the United Kingdom, sees most BFR training protocols in Britain initiated at three weeks post-op.

This type of training is not new. Yoshiaki Sato first described the technique as Kaatsu, in the 1970s. It gained popularity in North America approximately five or six years ago, according to Loenneke, when the bodybuilding community discovered it as a way to maximize muscle growth.

The premise is counterintuitive. The usual notion is that if you lift heavy things you build muscles, and if you lift heavier things, you build bigger muscles. With BFR training, one lifts only 20 to 30 percent of one’s heavy weight maximum. In general, the cuff pressure depends on the size of the cuff, the size of the limb and the individual’s blood pressure. Most protocols reduce blood flow by 80 percent.

Johnny Owens spent 10 years as the chief of human performance optimization at the Centre for the Intrepid, part of a military medical centre in San Antonio, Texas. He started using BFR training in the early 2000s on wounded soldiers as part of his rehab and recovery protocol. After leaving the service, he moved into sports medicine, where he worked with professional athletes using BFR to recover from injury.

Now, Owens’s team is among several groups doing research with elderly patients where the goal is avoiding muscle breakdown. Owen’s company provides BFR certifications to trainers and other medical professionals; through his website and courses, he sells his own equipment to those who have completed his training program.

A recent literature review done by the University of Guelph looked at the results of 400 young, healthy patients who participated in BFR training. The results appear promising and have shown consistent improvements in muscle strength and size. Practically, for those for whom higher load exercises are contraindicated, BFR training can help to maintain strength while reducing loads on tissues.

Another review looking at studies using BFR specifically as a rehabilitation tool found similar results. BFR training showed an increase in muscle strength and size and an ability to engage in this exercise earlier than heavy-load training.

Those with low muscle mass have the most to gain from this training, Owens says. “If you add a little bit of muscle to an elderly patient, they increase strength, power, muscle endurance.”

While clinically exciting, there remain concerns about moving from research to usual practice. One unknown is whether the technique helps patients change their level of function, improve their recovery process, and ultimately improve their quality of life.

In another potential use of BFR, building on research done by a group in Qatar, Patterson and his colleagues are studying how to optimize BFR protocols to reduce pain. Current information supports the idea that pain can be reduced for up to 24 hours following a BFR session. In a study of 25 patients with knee pain, patients reported decreased pain scores after completing BFR exercises. The exact mechanism behind the pain relief is still under investigation. If the results of this small study are confirmed, it could have big implications.