Have you seen any videos and/or posts on social media about the latest and greatest training fads? Do you want to know what is real versus imaginative? One training technique that seems to be popping up in the lifting world is Blood Flow Restriction (BFR) Training. This isn’t a technique just for the heavy lifters, rather it's a technique that has many beneficial applications in the rehabilitation setting as well. Firstly, this technique helps decrease the slowing of muscle loss often experienced due to restrictions set by injury or surgery. Secondly, it helps with hypertrophy (building muscle) during the recovery phase after surgery or injury. The more we look into the process, the simpler it becomes and the better it sounds. So, what is blood flow restriction training and how do we, as clinicians, use it to help you meet your goals with less pain and a faster recovery?
From Dr. Mario Novo at DrJohnRusin.com: "The concepts of muscle adaptation are steeped in the intricacies of manipulating mechanical stress and metabolic stress in order to create the prerequisite environment that is ripe for muscle hypertrophy. What we are learning now from Blood Flow Restriction Training is furthering the understandings of the underlying mechanisms that are required to stimulate muscle hypertrophy and how with this novel approach we may be able to reach a broader section of the lifting population with the potential to see changes occur at a safer and quicker rate when compared to traditional methods."
What is happening? Blood flow restriction training occludes venous return while maintaining arterial flow. In other words, blood flows in, but doesn’t flow out; nutrients come in but waste doesn’t go out. This induces protein synthesis as a direct response to proposed metabolic triggers that are required to stimulate muscle growth (Kubota et al 2008). As low loads continue in higher repetition sets (during exercise), there is an increase of low pH and potential low oxygen in the tissue environment (likely due to the buildup of waste products like lactate and hydrogen ions). This stimulates the same anaerobic pathways seen in heavy resistance training.
As clinicians, how are we using this technique to better help our patients? There is some evidence that suggests that BFR training is helpful for muscle hypertrophy and bone growth. Per Loenneke et al 2013: BFR "may actually be beneficial in healing injured bone." For those who are otherwise unhealthy, BFR training "produce similar post-exercise hypotensive results to that of resistance training with normal blood flow (Neto et al 2015)."
Normally, resistance training induces stress (mechanical or metabolic), which stimulates neuroendocrine "up regulation" of growth hormones and "down regulation" of inhibitory growth factors. This is completed in an attempt to balance the tissue and system. More from Dr. John Rusin: "A study aimed at BFR and its interaction with ischemic heart disease (Maderame et al 2013) reported positive safety finding as BFR did not adversely affect exercise-induced hemostatic and inflammatory responses."
As with any training or rehabilitative technique, there are risks and benefits. For those with deep vein thrombosis, pregnancy, varicose veins, high blood pressure, and cardiac disease, specialized care is taken in the clinic setting.