Blood Flow Restriction (BFR) Training
Blood flow restriction training is an important aspect of rehabilitation. You may be a candidate for blood flow restriction training during physical therapy as it allows earlier strengthening with less load and faster gains in strength when weakness is based on injury disuse or post-operative atrophy.
A common question we are asked is “Why do we want to restrict blood flow during exercise?” The answer is quite complex from a physiology standpoint. Blood flow restriction treatment is completed while you exercise using compression bands that allow blood flow to your muscles through the arteries. Once the circulation of blood reaches your muscles, the compressive bands create a reduction of the outflow of the blood through the veins from the muscles being exercised. This creates a physiological response not unlike heavy strength training – but without the heavy load which painful joints or injured tissue may not be ready to handle.
A systematic review was completed on BFR training in physical therapy after ACL reconstruction as well as in patients who had knee arthroscopy for knee osteoarthritis or patellofemoral pain syndrome. A systematic review is a study that involves a detailed and comprehensive plan and search strategy with the goal of reducing bias, and identifies, appraises, and synthesizes all relevant studies on a particular topic. In this case, BFR training.
This systematic review included 9 studies that met criteria. The results showed statistically significant improvements in quadriceps strength after BFR training. There were few benefits seen in quadriceps cross-sectional area. Blood flow restriction training proves effective in improving quadriceps strength in patients with knee-related weakness and atrophy.
What does blood flow restriction do?
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 due to surgery or arthritis in a joint.
The compression cuffs used with blood flow restriction treatments are similar to blood pressure cuffs. Arterial blood flow is allowed into the extremity, but venous outflow is reduced, which creates the hormonal response and tricks your system into thinking that it is completing high intensity exercise.
Blood flow restriction creates temporary hypoxia (decreased oxygen) in the muscles of the areas being exercised. While this may sound concerning, the local hypoxia actually helps in accumulating more metabolites. This helps to regulate the body’s anabolic (growth) response system which is the way the body gains muscle protein during exercise. Essentially, restricting blood flow in the affected area helps to build more muscle protein which equates to increased strength.
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.
Will blood flow restriction benefit me?
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.
Is blood flow restriction training safe?
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 can 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.
When completing the exercises, the intended goal of blood flow restriction is to tire out the affected area, in order to stimulate the body’s natural healing and tissue-building processes. After treatment, muscle soreness may occur for the next day or two, and “limb fatigue” may occur for 20-30 minutes but should disappear shortly.
Contact Rose City Physical Therapy Today to Inquire About Blood Flow Restriction Training
If you are recovering from an injury or surgery, and you are interested in potentially participating in blood flow restriction treatments, don’t hesitate to contact our Portland, OR office today. Our physical therapists are specialty trained in performing BFR training in rehab, and they would love to discuss how it may benefit you personally.
Contact Rose City Physical Therapy today at Portland, OR to request an appointment and get started on the path toward pain relief, increased strength, and overall functional improvement!