What is Blood Flow Restriction Therapy (BFR)?
When performing resistance training to build muscle and strength, the resistance during an exercise is traditionally relatively high.
Blood Flow Restriction (BFR) therapy uses an external cuff around the top of a patient’s arm, thigh or calf which is pumped up to a certain pressure to reduce blood flow to the muscles. Exercises are then performed working the muscles below the cuff. By wearing the pressure cuff during exercise, the muscles are put under stress which helps to build muscle mass and strength. However the key point is that by using BFR, the exercises can be performed at a much lower intensity to achieve similar effects in muscle mass and strength as high load resistance training. This makes it suitable for use during rehabilitation.
How does it work?
Mechanical tension and metabolic stress are two of the main processes that occur within the tissues during exercise to trigger an increase in muscle mass. It is thought that using BFR during exercise reduces the mechanical tension on the muscles due to the lighter loads used but increases the metabolic stress.
Normally during resistance exercise, mechanical tension would increase production of hormones, such as growth factors, muscle fibre recruitment, protein synthesis and cell reproduction which helps to initiate the process of building muscle mass. Even though BFR uses a lower level of mechanical tension it also stimulates a similar metabolic stress to high load resistance training but at a lower load.
Metabolic stress is created through the accumulation of products such as lactic acid within the muscle during exercise. In BFR, metabolic stress is increased as oxygen levels in the tissues is reduced due to the pressure cuff restricting the blood flow in and out of the muscles below the cuff. It is therefore thought that by increasing the metabolic stress through exercise with BFR, processes responsible for hypertrophy (building muscle bulk) are stimulated due to factors such as increased hormone production and increased muscle fibre recruitment which in turn help to increase cell reproduction and signalling of muscular proteins to help build muscle.
How is BFR used in rehabilitation?
There are significant benefits to having a lower level of mechanical tension when it comes to rehabilitation and it can be particularly beneficial during rehabilitation of knees and ankles that have undergone surgery.
This reasoning behind this is that BFR during exercise produces similar muscular adaptations to those produced by high load training. This is particularly significant in scenarios during rehabilitation that high load training is not advised, for example following Anterior Cruciate Ligament reconstruction or Achilles tendon repairs. Additionally, BFR has been shown to result in significantly lower levels of knee pain compared to high load resistance training, this is thought to be due to the lighter loads that are used within BFR training.
There is also evidence to support the use of exercise training using a BFR pressure cuff in people with knee osteoarthritis for those who are unable to perform high intensity training.
If you are interested in finding out some more information about BFR and to see if it would be suitable for you, please don’t hesitate to get in touch either by phone or email using the details below. Alternatively if you would like to book an appointment, this can be done through our website or by giving us a phone.
Telephone number: 07470639020
The above information was very kindly researched and written by physiotherapy student, Anna Fraser. Thanks Anna!