Blood Flow Restriction Training (BFRT) is a training method used to improve strength gains and increase muscle mass using low-load techniques. This is great for clients who have undergone surgery; total hip replacement, total knee replacement, ACL, rotator cuff, etc and are not able to lift heavier weights or participate fully in cardio due to protocol. BFRT is also used for the athlete population who would like to improve muscle strength without heavy lifting and possible injury.
A cuff is used around the upper or lower limbs and inflated (by a PT) to a certain pressure in order to constrict blood flow in that area. By doing this, we cause a decrease in oxygen coming to the muscle which in turn allows the muscle to build up lactic acid and turn on our bigger/faster muscle fibers called Type II fibers which lead to increased protein synthesis (big breath here, it will all make sense, I promise). This allows those clients to continue to build muscle without causing damage to the structures they need to protect.
Now, not to continue to bore you with the science and physiology of this – here is an example of how this is used in our Physical Therapy Clinic.
If a client comes in following total knee replacement or ACL surgery, a protocol is in place to protect the joint and muscles around that particular area. For the client to gain strength without straining the area that has just been operated on, we can use BFRT. This will slow down the process of muscle atrophy (wasting) and allow the client to build muscle and increase strength safely.
Client is seated on mat table. Cuff is placed around top of the thigh and inflated to the proper pressure needed to decrease blood flow to the thigh muscles for a short period of time. The client is instructed in leg exercises that you would normally do with higher weights/body weight and instead can do with light weights to get similar results. This allows the client to fully participate in physical therapy without causing injury while GAINING strength. Here is an example of one exercise being done to improve quadricep strength using the BFR cuff.
But how is restricting blood flow not dangerous??? Research studies have shown that the negatives to this treatment are extremely low. Symptoms such as redness in the area or feeling of numbness (goes away when cuff is taken off) are the most common. Physical therapists who are trained in this technique have proper training to ensure your safety. Your PT will evaluate you and go over your medical history prior to introducing this method of strength training. This type of strength training is used with a variety of populations and can be the proper fit for many people!
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