This is the successor in the series of BFR for BIG arms. This time around we run through the nuts & bolts obtained from the cutting-edge research in Blood Flow Restriction.
By applying Blood Flow Restriction (BFR) muscles are simply stimulated at a lower working rate compared to Free Flow Conditions. Or alternatively, the metabolic stress and low-load exercise let’s your reach the effective rep range faster compared to conventional training.
For most people similar explanations would do the job, if not, then keep reading for a more comprehensive explanation of why BFR has proven its worth for hypertrophy!
As a rule of thumb, muscles adapts to mechanical and/or metabolic stimuli. Mechanical being the external load on the muscle whereas metabolic being the exertion of the muscle during repetitive or static work. The great thing about BFR is that you reach the state of exertion/fatigue much faster compared to conventional resistance training – BFR simply reduces the repetitions needed to build muscle by 30-50%.
When blood flow is partially restricted the transportation of oxygen is also reduced which changes the energy demand and increases the speed in which muscle fatigue occurs. This partial hypoxic (no oxygen) state means that the type 2 muscle fibers are being recruited at a rapid rate. When lactate and other metabolites accumulates because of glucose break down even more muscle fibers are being recruited.
BFR + cell swelling + mechanical tension creates metabolic stress leading to swift muscular exertion. – Activation of mTor and downregulation of myostatin, as the most important hormonal responses leading to increased protein synthesis.
Combined with the repeated bout effect e.g. regular training, we have a finale recipe for hypertrophy.
As some of the ingredients are up for debate, like cell swelling (the primary rational for passive BFR) and lactic acid as a direct anabolic pathway for collagen production (tendon health), please do not hesitate to comment!?
Source:
Klein et al. (2001) Flexor tendon wound healing in vitro: the effect of lactate on tendon cell proliferation and collagen production.
Jessee et al. (2018) Mechanisms of Blood Flow Restriction: The New Testament.
Sleboda et al. (2019). Internal fluid pressure influences muscle contractile force.
Dr. Nicholas Rolnick (2020) 13 Module Online Video Course – Blood Flow Restriction.
