Who should use BFR training?

Research supporting the use of BFR training has grown tremendously since the turn of the century. The use of pneumatic cuffs, elastic straps and tourniquets to restrict blood flow during exercise has been proven safe and effective in many different populations. In a nutshell, BFR training enables users to achieve substantial resistance and aerobic training results using a low-intensity stimulus, comparable to what you may otherwise achieve using more traditional methods. The purpose of this blog is to explore which sub-groups could benefit the most from this form of training.

Why is BFR training beneficial?

Using a low-intensity training stimulus such as walking and light resistance exercise, exposes users to a low mechanical load. This means less force going through bones, tendons, muscles and joints. BFR training was traditionally used as a strategy to increase muscle mass (What is BFR?), however more recent studies tell us that the benefits may extend to the bones, tendons, heart and blood vessels. This means that people who are typically considered contraindicated to high intensity exercise, such as those who are injured, the elderly, or those in poor health, may still benefit from rigorous physical activity. A recent survey of practitioners currently using BFR revealed that the most common objectives of BFR exercise was to induce muscle hypertrophy, followed by use during injury rehabilitation. Universities and elite or professional sporting teams are the most frequented users of BFR, with the age bracket of 21-30 years being the most common age bracket (Patterson et al. 2017).

Who can benefit from BFR training?

BFR training is a relatively new training technique. New research is being developed everyday, among which are various case studies. Although case study analysis may represent the lowest form of scientific rigour, it provides us with unique insight as to which sub-groups of our population may benefit from BFR. While the applications of BFR are limited only by a practitioners imagination, I will dedicate the remainder of this post to identifying the top 3 groups of people who I believe can benefit from BFR.

Honourable mention - Clinical disease

As we refine BFR training techniques to make them safer and more effective (BFR and Safety), ongoing research is exploring the use of BFR in clinical populations. The application of BFR has been shown to be effective at reducing disuse atrophy associated with physical disability in intensive care patients, while in combination with very low-intensity exercise such as walking has been shown to increase physical function and muscle strength in clinical populations. Specifically, a case study analysis in a 65-year old diagnosed with Parkinson disease demonstrated that a 6-week BFR training intervention comprised of 5x2min bouts of walking was sufficient to increase physical function and alleviate the subjects symptoms (Douris et al., 2018). Similar results have been seen in subjects with polymyositis, an inflammatory disease characterized by severe muscle weakness (Mattar et al., 2014), and elderly women diagnosed with osteoporosis (Silva et al., 2015). As more research becomes available attesting to the safety and applicability of BFR training to a wide range of subjects, I have no doubt this form of training will become a prominent rehabilitation strategy in many diseased states where disuse atrophy and deteriorating physical function are common symptoms. Further research supporting the clinical efficacy of BFR training in disease is required before this can occur.

3 - Elite athletes

The training and competition demands of an elite athlete are always increasing. In many cases, athletes are required to train and compete year-round, across the world, and often with minimal access to training equipment. These intensive physical demands often mean athletes are constantly managing minor injuries and training through pain. A low-cost, low-intensity training system, that exposes their weary bodies to minimal additional mechanical load, while triggering improvements in muscle mass and muscle strength could be a useful addition to an athletes training regiment. Further, the world of elite sport is always searching for the additional 1% improvement in performance that could be the difference between victory and defeat. More recent research has demonstrated that, when coupled with high-intensity exercise, BFR may trigger a greater training effect than high-intensity exercise alone (Taylor et al., 2016).

2 - Injury rehabilitation

BFR training is often targeted at people who are considered to be 'load-compromised' or contraindicated to high-intensity training. The most obvious sub-group to whom this term applies are people going through an injury rehabilitation. BFR has been proven an effective rehabilitation strategy in many clinical populations, with the majority of research focused on ACL reconstruction, patellofemoral joint pain, knee arthroscopy and tendinopathy. For use in injury rehabilitation, there are typically 3 strategies in which BFR is commonly used. The first involves BFR applied in the absence of an exercise stimulus. Passive BFR has been shown to reduce the muscle loss that is commonly associated with post-surgical physical inactivity, particularly in ACL reconstructed patients (Takarada et al 2000). The second, is BFR combined with neuromuscular electrical stimulation (NMES). This is another passive for of BFR training with an externally produced muscle contraction. BFR and NMES can increase muscle strength and thickness, even in the absence of physical exercise (Natsume et al 2015). The third strategy is in combination with low intensity resistance exercise. When this form of training is completed, improvements in strength and muscle mass comparable to high-intensity training can be achieved without exposing the injured site to high mechanical loads.

1 - Elderly people

Finally, the number 1 sub-group who can benefit from BFR is the elderly. Number 1 on this list was an easy decision to make. Physical inactivity associated with ageing leads to muscle wastage, a process called sarcopenia. These decrements are associated with the onset of disease including diabetes, cardiovascular disease and accidental death from falls. Meanwhile, the relationship between muscle strength and physical function is linear and most robust in weaker older adults. A training intervention that can maintain muscle mass amongst the elderly using low-intensity and low-cost training methods has astounding potential to improve health and quality of life. A recent systematic review of the literature demonstrated a unanimously positive effect of BFR training on muscle strength and muscle mass, regardless of the BFR protocol used in the study (Cardoso et al., 2019). BFR has been consistently shown to increase muscle strength, physical function and quality of life in elderly populations and is an exciting area for this training method to evolve.

The final word:

The BFR framework offers many of the benefits of high-intensity resistance training, using a low-intensity stimulus. Who will benefit from this form of training is purely subjective and not necessarily limited to the four sub-groups listed above. There remains a lot to be learned about the most effective ways to implement BFR training, but there is sufficient evidence to suggest that it could be a particularly useful training tool in both load-compromised and healthy individuals.

References:

Patterson, S.D., Bradner, C.R. The role of blood flow restriction training for applied practitioners: A questionnaire-based survey. Journal of Sport Sciences, 2018. 36(2): p 123-130. https://pubmed.ncbi.nlm.nih.gov/28143359/ Douris, P.C., et al. The results of blood flow restriction training on functional improvements in an active subject with Parkinson Disease. The International Journal of Sports Physical Therapy, 2018. 13(2): p247-254. https://pubmed.ncbi.nlm.nih.gov/30090683/ Mattar, M.A., et al, Safety and possible effects of low-intensity resistance training associated with partial blood flow restriction in polymyositis and dermatomyositis. Arthritis Research & Therapy, 2014. 16: p1-8. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4232679/ Silva, J., et at. Chronic Effect of Strength Training with Blood Flow Restriction on Muscular Strength among Women with Osteoporosis. Journal of Exercise Physiology Online, 2015. 18(4): p33-41. https://www.researchgate.net/publication/280835919 Taylor, C.W., et al. Acute and chronic effect of sprint interval training combined with postexercise blood-flow restriction in trained individuals. Experimental Physiology, 2016. p143-154. https://pubmed.ncbi.nlm.nih.gov/26391312/ Takarada, Y., et al. Applications of vascular occlusion diminish disuse atrophy of knee extensor muscles. Medicine & Science in Sport & Exercise, 2000. p2035-2039. https://pubmed.ncbi.nlm.nih.gov/11128848/ Natsume, T., et al. Effects of Electrostimulation with Blood Flow Restriction on Muscle Size and Strength. Medicine & Science in Sport & Exercise, 2015. p2621-2627. https://pubmed.ncbi.nlm.nih.gov/26110693/ Cardoso , R.K., et al. Effect of training with partial blood flow restriction in older adults: a systematic review. Brazilian Journal of Kinanthropometry and Human Performance, 2019. p219-228. https://www.researchgate.net/publication/325380058