Background
Originating in Japan by Yoshiaki Sato and previously known as Kaatsu training, blood flow restriction training (BFRT) is the temporary occlusion of blood flow.
Blood flow restriction training uses pressure high enough to occlude venous return, yet low enough to maintain arterial inflow into the muscle. Restricted pressure should be relative to each individual and be dependent on both cuff width and the size of the limb to which blood flow restriction is being applied.
Why use it?
A large amount of research now supports BFRT combined with low-load resistance training to achieve significant improvements to physical function. Benefits include improvements to:
Muscle size and strength
Bone health
Cardiovascular health including VO2 max
It is typically suggested to use moderate to high intensities of resistance training to stimulate muscle strength and hypertrophy. However, there are many factors that may limit us from doing so:
pain,
tissue capacity being low,
weight-bearing/load precautions following injury,
or simply the fact that a person cannot tolerate the effort/fatigue
Practical examples:
A limb has been immobilsed in a cast
BFRT can be used to reduce the weakening of muscle, and limit functional declines in muscular strength and joint stability
Following an operation
BFRT can reduce injury risk and speed up recovery by using exercise with light loads such as walking and cycling. This can lead to small but significant improvements in the strength and muscle size.
BFRT can help improve muscle activation, perfusion, and endurance following surgeries such as ACL reconstructions.
Athletic population
BFRT can help to reduce fatigue and mechanical stress on the body, while still creating enough physiological stimulus for muscle hypertrophy and strength, therefore assisting with sporting performance, and potentially increasing an athlete’s longevity in a sport.
How does it work?
There is no definitive description on how BFRT works, but here are two proposed mechanisms:
BFRT increases production and stimulates mechano-growth factors and increases signalling of protein synthesis pathways at a cellular level
Hypoxic environments (i.e. reduced oxygen) and metabolite accumulation (i.e. blood lactate) are hypothesised to result in increased type II muscle fiber recruitment to maintain force production and protect against muscular failure
Effectiveness
Below is a summary of evidence on the effects of BFRT compared with high intensity training and stand alone low intensity exercise.
Safety considerations
With BFRT, one of the biggest concerns is safety. Common side effects relate to subcutaneous haemorrhage and numbness. However, these symptoms are often experienced at the beginning of a BFRT program and dissipates when the individual becomes more used to the type of training.
Contraindications include:
History of deep-vein thrombosis
Pregnancy
Varicose veins
High Blood pressure
Cardiac Disease
Rhabdomyolysis
Precautions include:
Subcutaneous hemorrhage
Numbness
DOMS
“Feeling Cold”
Guidelines for use
Frequency 2.3 times a week (>3 weeks) or 1-2 times per day (1-3 weeks)
Load 20-40% 1RM
Restrictive Time 5 - 10min per exercise (reperfusion between exercises)
Type Small and large muscle groups (arms and legs/uni or bilateral)
Set 2 - 4
Cuff 5 (small), 10 or 12 (medium), 17 or 18cm (large)
Repetitions Pressure (75 reps) - 35 x 15 x 15 x 15, or sets to failure 40-80% AOP
Rest between sets 30-60 secs
Restriction form Continuous or intermittent
Execution speed 1-2 sec (concentric and eccentric)
Execution Until concentric failure or when planned rep scheme is complete
Summary
BFRT training shows promising results when used in a variety of setting. While it may not be suitable as a replacement for traditional resistance training, it can be an effective option during early stages of rehab where there a limitations to how much mechanical stress the individual can tolerate. BFRT offers a way of improving physical condition and function, whilst keeping exercise intensity low to improve tolerance.
References
DePhillipo, N. N., Kennedy, M. I., Aman, Z. S., Bernhardson, A. S., O'Brien, L. T., & LaPrade, R. F. (2018). The role of blood flow restriction therapy following knee surgery: Expert opinion. Arthroscopy: The Journal of Arthroscopic & Related Surgery, 34(8), 2506-2510.
DePhillipo, N. N., Kennedy, M. I., Aman, Z. S., Bernhardson, A. S., O'Brien, L., & LaPrade, R. F. (2018). Blood Flow Restriction Therapy After Knee Surgery: Indications, Safety Considerations, and Postoperative Protocol. Arthroscopy techniques, 7(10), e1037-e1043.
Franz, A., Queitsch, F. P., Behringer, M., Mayer, C., Krauspe, R., & Zilkens, C. (2018). Blood flow restriction training as a prehabilitation concept in total knee arthroplasty: A narrative review about current preoperative interventions and the potential impact of BFR. Medical hypotheses, 110, 53-59.
Fry, C. S., Glynn, E. L., Drummond, M. J., Timmerman, K. L., Fujita, S., Abe, T., ... & Rasmussen, B. B. (2010). Blood flow restriction exercise stimulates mTORC1 signaling and muscle protein synthesis in older men. Journal of applied physiology, 108(5), 1199-1209.
Hughes, L., Paton, B., Rosenblatt, B., Gissane, C., & Patterson, S. D. (2017). Blood flow restriction training in clinical musculoskeletal rehabilitation: a systematic review and meta-analysis. Br J Sports Med, 51(13), 1003-1011.
Hylden, C., Burns, T., Stinner, D., & Owens, J. (2015). Blood flow restriction rehabilitation for extremity weakness: a case series. J Spec Oper Med, 15(1), 50-6.
Image obtained from https://mikereinold.com/the-science-of-blood-flow-restriction-training/
Loenneke, J. P., Wilson, J. M., Wilson, G. J., Pujol, T. J., & Bemben, M. G. (2011). Potential safety issues with blood flow restriction training. Scandinavian journal of medicine & science in sports, 21(4), 510-518.
Loenneke, J., Abe, T., Wilson, J., Thiebaud, R., Fahs, C., Rossow, L., & Bemben, M. (2012). Blood flow restriction: an evidence based progressive model. Acta Physiologica Hungarica, 99(3), 235-250.
Manini, T. M., Yarrow, J. F., Buford, T. W., Clark, B. C., Conover, C. F., & Borst, S. E. (2012). Growth hormone responses to acute resistance exercise with vascular restriction in young and old men. Growth Hormone & IGF Research, 22(5), 167-172.
Patterson, S. D., Hughes, L., Warmington, S., Burr, J. F., Scott, B. R., Owens, J., ... & Neto, G. R. (2019). BLOOD FLOW RESTRICTION EXERCISE POSITION STAND: Considerations of Methodology, Application and Safety. Frontiers in physiology, 10, 533.
Scott, B. R., Loenneke, J. P., Slattery, K. M., & Dascombe, B. J. (2015). Exercise with blood flow restriction: an updated evidence-based approach for enhanced muscular development. Sports medicine, 45(3), 313-325.
Tennent, D. J., Hylden, C. M., Johnson, A. E., Burns, T. C., Wilken, J. M., & Owens, J. G. (2017). Blood flow restriction training after knee arthroscopy: a randomized controlled pilot study. Clinical Journal of Sport Medicine, 27(3), 245-252.
Thomas, K. (2019). The benefits of blood flow restriction training for rehabilitation. Co-Kinetic Journal, (79).
Tuncali, B., Boya, H., Kayhan, Z., & Arac, S. (2018). Tourniquet pressure settings based on limb occlusion pressure determination or arterial occlusion pressure estimation in total knee arthroplasty? A prospective, randomized, double blind trial. Acta orthopaedica et traumatologica turcica, 52(4), 256-260.
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Wilkinson, B. G., Donnenwerth, J. J., & Peterson, A. R. (2019). Use of Blood Flow Restriction Training for Postoperative Rehabilitation. Current Sports Medicine Reports, 18(6), 224-228.
Zeng, Z., Centner, C., Gollhofer, A., & König, D. (2019). Blood-Flow-Restriction Training: Validity of Pulse Oximetry to Assess Arterial Occlusion Pressure. International journal of sports physiology and performance, 14(10), 1408-1414.