Blood Flow Restriction training

After Training

What is BFR?

MSK Doctors offers Blood-flow restriction (BFR) training which is an emerging technique demonstrating efficacy in orthopaedic rehabilitation. This method involves partial vascular limb occlusion, specifically venous occlusion, using proximally placed inflatable cuffs. With the cuffs placed, the patient then performs low-load (LL) exercises which in turn leads to muscle hypertrophy, strength gains, enhanced oxygen delivery and utilisation (VO2Max).

How does BFR work?

Blood flow restriction training research has been around for the last decade and has looked at everything from using BFR in individuals that are immobilised to reduce atrophy, all the way to NASA investigating how to use BRF to protect skeletal muscle integrity while in the confines of zero G.

BFR has some known mechanisms, and they are as follows:

Lactic acid – metabolite mechanism: simply stated, applying a compression band or tourniquet around a limb will stave off muscle atrophy by means of metabolic accumulated chemical stress. BFR training works by enhancing the production of muscle metabolic by-product or waste such as lactic acid, and hydrogen ions (H+). These metabolites are chemical irritants to the muscle which stress muscle tissue and surround tissues to respond by adaptation known as super compensation. Protein synthesis is one adaptation that yields the formation of newly formed muscle proteins which can increase the storage of more muscle glycogen.

Cell Swelling Mechanism – As a direct result of venous blood flow occlusion, there continues to be an increase in fluid into the working muscle. This leads to a characteristic swelling pump. While muscles are contracting, they push fluid away from themselves much like a sponge being squeezed. As the fluid pressing decreasing in the working muscle, upon relaxation of the contraction, fluid rushes inward. As there is an accumulation of fluid and metabolite build up which attracts more fluid, the muscle cells begin to engorge. As they increase in size there is a stress placed on the cellular walls. This stress leads to a protective response again leading to adaptations and growth.

Elliptical Machine

Why should we use it clinically and what are the benefits?

To stimulate increases in muscular size and strength, it is generally recommended that resistance training utilises high-intensity exercises with 70% of an individual’s one repetition maximum (1RM). Despite this, post-surgical and elderly patients may be unable to tolerate such high intensities due to several factors, including pain and co-morbidities. Therefore, BFR training presents an attractive clinical approach as it allows comparable muscular gains to high intensity resistance training yet with as little as 30% of a patients 1RM and in shorter periods of time. Other cited clinical benefits include: hypoalgesia increasing patient engagement and reduced joint stress due to the use of lower loads.