Blood Flow Restriction Training
By Georgia Koutrouvelis
Patellofemoral (knee cap) pain is a very common injury which we see in both males and females, and adolescents and adults.
The effectiveness of increasing quadriceps strength to reduce patellofemoral (knee cap) pain has been well established in the literature. In order to achieve true strength changes, the use of high intensity training at a load greater than 70% of one-repetition maximum is required. This high resistance not only loads up the quadriceps, but also the patellofemoral joint.
The people who would mostly benefit from quadriceps strengthening are those with kneecap pain, but unfortunately, they can experience a flare up of their discomfort during high load strengthening exercises. We also know that quadriceps activity is reduced in the presence of knee cap pain, so the notion of exercising into pain thresholds is not recommended.
So, this raises the following questions:
How do we increase quadriceps strength, in the presence of patellofemoral pain?
A recently researched option is Blood Flow Restriction Training (BFRT).
What is Blood Flow Restriction Training?
Research on BFRT was first published in Japan as Kaatsu training in 2000. The aim is to increase both muscle strength and size through by exercising under reduced blood flow conditions to and from the muscles. A sphygmomanometer (blood pressure cuff) is used to apply the pressure restriction at a desired measurement.
Does it work?
Yes. In 2012, a meta-analysis of all the literature illustrated the effectiveness of using BFRT as a method of increasing both muscle strength and size. These changes were achieved by using only 30% of one- repetition maximum (as compared to the 70% required with traditional strength training).
Is it safe?
A review of the literature in 2011 showed that BFRT appears to be as safe as traditional strength training methods. Although this is quite a safe intervention, any potential participants will still undergo a medical screening questionnaire to assess their relative risk.
How does it work?
The physiological mechanisms behind BFRT training aren’t very well understood, however we do know that there is a build-up of metabolic waste product within the muscle, an increase of growth hormone factor greater than traditional strength training, and reduced oxygen to the muscle.
Will it change my patellofemoral pain?
A published studied in 2016 compared an eight-week traditional strength training program with and eight week BFRT program, to assess whether there was a significant change in pain, function, quadriceps strength and size in patients experiencing patellofemoral joint pain. I assisted in this study by being a facilitator of the intervention. The intervention compared eight-week training program, 3 times a week, of knee extension and leg press exercises. One group performed the program under traditional strength training, methods (70% one-repetition maximum) and the other under BFRT conditions (with partial occlusion via a blood pressure cuff, at a resistance of 30% one-repetition maximum). The patients who demonstrated significant changes in daily levels of pain were those with knee cap pain on resisted knee extension and runners.
Who should I consider BFRT?
- If you have patellofemoral pain and traditional quadriceps strength training is too painful
- If you would like to increase quadriceps strength but high levels of load on the knee is not appropriate in the short term or longer term. For example, post-operative patients, those with patellofemoral osteoarthritis
For more information or to book an appointment with Georgia Koutrouvelis, please contact Reception 9596 9110.