Lead Photo: Courtesy of B Strong Training System

What is Blood Flow Restriction (BFR) Training?

Whether facing a long surgery such as an ACL reconstruction or rotator cuff repair, or fracture recovery with precautions, or insurance limits and higher out of pocket costs, methods to help assist with strength gains is crucial. Blood Flow Restriction (BFR) training is a technique which creates a hormonal response to trick the body into thinking it is completing high intensity exercise and leading to gains high intensity exercise provides, despite actually utilizing low intensity and lower load based exercise. This is especially important for patients and athletes that have restrictions due to surgery, fractures, soft tissue and bone health, and limited load allowances or tolerances.

How does Blood Flow Restriction Training Work?

Blood flow restriction partially restricts arterial blood flow to your tissue while completing restricting venous flow (return from you tissue to your heart) during exercise. Pneumatic compression cuffs are placed around the upper arm and/or upper thigh and a pump is used to inflate the cuffs to a safe calibrated level of pressure, creating a tourniquet effect. This in turn causes a lack of oxygen for the muscles and stimulates physiologic responses in the body that mimic that of heavy resistance training. Exercise is completed with the cuffs in place.  You will find increased intensity and difficulty of exercise with BFR that otherwise would not prove as challenging.

The History of Blood Flow Restriction Training

The technique dates back to 1966 in Japan when Yoshiataki Sato noticed after being in prolonged kneeling, his legs felt similar to how they felt after strength training. In 1973, he had an ankle and knee injury while skiing.  He experimented with occlusion training while in a cast. After six weeks, his physicians were impressed with the minimal strength loss, despite the cast. Thereafter, over the years he tested various ways to restrict blood flow until KAATSU was developed in the 1990’s and the first research was published. Occlusion training and use was limited initially to Japan. In the last 20 years, research appeared in Western medical journals after the technique was used in the US Military for recovery post traumatic injury.  In the last 10 years, more frequent mainstream use has occurred in sports and physical therapy.

Benefits of Blood Flow Restriction Training

Research shows that strength gains and muscle hypertrophy (growth in size) is significantly greater with BFR training, than with low resistance exercise alone. These gains can occur within weeks, and are similar to high intensity and heavy load resisted exercise. Exercise recommendation is 20-40% of one’s 1-repetition max (RM), higher repetitions, frequent rest breaks, sessions of 20 minutes or less, 2-3 times a week, and for a duration of greater than 3 weeks. Blood Flow Restriction can also be added to aerobic exercise such as walking and cycling with research showing carryover for improved function for daily activity, aerobic capacity, and health. There are some limits due to the comfort of wearing the bands during cardiovascular exercise. Other promising benefits include pain control, bone healing, increased bone density, accelerated tendon injury recovery, and a complement after Platelet-rich Plasma (PRP) and Stem cell regenerative injections.

An understandable concern is safety. Research actually reports decreased deep vein thrombosis (DVT) risk and lower hypertensive response with exercise. Muscle damage can occur without the use of proper equipment as well, as not following instructions. The technique is not recommended for those who are pregnant and requires surgeon approval post-operatively and post fracture, and for cardiovascular medical conditions.

Is Blood Flow Restriction Training Right for Me?

To summarize, BFR training provides another tool for physical therapy treatment to increase strength gains sooner and with less load on injured tissue or during post-operative precautions.  Some of the exciting uses include post-operative rehab, fracture management recovery, athletes cross-training, load management, for the elderly, and for those with arthritis. Safe use requires medical guidance and adherence to established compressive loads applied to the cuffs. If your physical therapist and physician adds BFR training to your plan of care, expect to work hard, but the reward will be earlier increased strength and muscle muscle mass and quicker return to function.

Blood Flow Restriction Training

Left: B Strong BFR cuff set up on a patient’s thigh. Right: US Ski Team and Olympian Jacqueline Wiles using B Strong BFR during rehab at Rose City Physical Therapy

The physical therapists at Rose City Physical Therapy have been formally trained in Blow Flow Restriction using the B-Strong BFR Training System ™ co-developed by sports medicine physician and researcher Dr. Jim Stray-Gundersen, MD.