Blood Flow Restriction (BFR) Training: Gaining Strength When Heavy Load Isn’t an Option

To improve the strength, size, and function of a muscle it is well known that moderate to high loads must be used to provide the necessary stimulus for tissue adaption.  For those with injuries to a particular area this becomes a problem as they typically cannot tolerate exercises of a high enough intensity to stimulate the necessary changes needed to see true gains in strength and/or size.  

For individuals not able to tolerate moderate to heavy weights, blood-flow restriction (BFR) training has been found to be very helpful.  BFR is a training modality that involves the use of a specialized tourniquet (cuff) applied to the proximal aspect of a limb (usually at the upper arm or thigh) to induce occlusion of blood flow within the extremity. The cuff is typically inflated to a level which is adequate to impede all venous return while still allowing for partial arterial flow.  Then, individuals typically perform an exercise utilizing 20-30% of their maximum with high repetitions (15-30 reps) for 3-5 sets with brief rest breaks of 30 seconds between.  This protocol was formed following research conducted to determine an effective protocol to facilitate improvements in muscle strength and size using the BFR technique. 

Sounds too good to be true.  How is BFR able to achieve such impressive results with using low loads?  Simply put, BFR training induces a hypoxic (low oxygen) environment within the muscle while also allowing for swelling within the limb from an accumulation of blood.  These effects lead to an increase metabolic stress, increased cell swelling, activation of myogenic stem cells, and a release of anabolic hormones such as human growth hormone (HGH) and IGF-1. This combination of factors creates an environment within the muscle that stimulates increases in muscle strength and size. 

 At first glance, you may think the concept sounds dangerous. However, BFR has been found to be safe when applied appropriately and in individuals without contraindications for treatment.  For this reason, it is important to consult with a practitioner trained in BFR prior to beginning a protocol. This will ensure allow for proper assessment of risk factors prior to implementing the protocol. If you’d like to know more about BFR or think it may be a useful to you, then reach out to one of our experts to learn more!

By Nick Bechtold, PT, DPT, OCS, CSCS, CF-L1