Blood Flow Restriction Training- What is it and why should I do it?
You’ve seen people in the gym working out with a contraption around their leg or arm. I’m sure you’ve wondered to yourself, “What the heck is that?” “Why is their limb purple?” “ Should I be doing that?” Or maybe, a healthcare provider has told you to begin a blood flow restriction program and you want to know more. You’re in the right spot. Let’s spend time breaking down what blood flow restriction training (BFR) is and why you would want to begin a BFR program.
What is Blood Flow Restriction Training?
Blood flow restriction (BFR) training is an intervention that applies a pressurized cuff to either the upper thigh or upper arm that partially occludes blood flow during an exercise program. This mechanism allows for an exaggerated response to low load training in regards to increasing muscle strength, hypertrophy and cardiovascular performance. Research supports that training in a hypoxic (without oxygen) state allows a metabolic response to occur that enables users to train at reduced loads while still achieving the same benefits as training under higher loads. Historically, heavy exercise loads of approximately 75% of an individual's one repetition maximum (1RM) have been deemed necessary to elicit muscle hypertrophy and strength gains. In recent years, research has demonstrated that augmentation of low-load resistance training with blood flow restriction to the active musculature can produce significant hypertrophy and strength gains, using loads as low as 20 1RM. BFR training has been found to yield hypertrophy responses , as well as physiologic adaptations, comparable to that observed with heavy-load resistance training. The aim of BFR training is to mimic the effects of high intensity exercise by recreating a hypoxic environment using a cuff during low load exercise.
Who uses BFR?
Postoperative
As we have already discussed, we can mimic training at high loads with the use of low-load resistance training with BFR. This is helpful for individuals post operative that cannot bear weight, or, cannot yet tolerate training at higher loads. In this instance, BFR is used to prevent atrophy and promote hypertrophy in order to accelerate one’s ability to be able to tolerate heavy resistance training. The research even shows that being in a blood flow restricted state without exercising prevents atrophy in postoperative populations. How cool!
Bone Degradation or Bone Injury- Osteoarthritis, osteoporosis, stress fractures
BFR has been shown to have a positive impact on bone health. BFR can be used to promote bone turnover. Bone gets stronger by responding to the stresses we put on it. Due to injury or pain, we cannot always handle stressing our bodies with heavy loads. Training with low loads in a blood flow restricted state has been shown to increase bone formation. In addition, BFR has been shown to decrease exercise related pain. This is especially helpful for those with osteoarthritis that experience pain with resistance exercise.
Soft Tissue Injury
BFR is also used to promote muscle, tendon and ligament healing. After you experience injury to a soft tissue structure, pain is a big limiting factor of function. In order to return to normal function, we need to gradually stress the soft tissue to promote healing. Doing so with BFR training is shown to be more tolerable and more efficient.
Improve VO2 Max
Blood flow restriction training can be used to maintain or improve aerobic capacity when HIIT or endurance training is not appropriate (i.e. injured populations). BFR has been shown to improve aerobic performance by increasing VO2max. A study by Abe et al. found that BFR cycle training for 15 minutes for 4 weeks improved VO2max by 6.4% and increased exercise time until exhaustion by 15.4%.
Sarcopenia (loss of muscle tissue as a natural part of the aging process)
BFR training has been shown to stimulate mTORC1 signaling (cell growth) and muscle protein synthesis. In populations with sarcopenia, BFR has been shown to prevent muscle loss and improve functional fitness.
Conclusion
All in all, BFR training is used as a progressive clinical rehabilitation tool in the process of return to heavy-load exercise. Blood-flow restriction training can help patients to make greater strength training gains while lifting lighter loads, thereby reducing the overall stress placed on the limb. Many populations can benefit from the use of BFR training. Talk with your physical therapist to determine if BFR training is right for you.
Check out these videos with more BFR info!
