Blood Flow Restriction… Why Would I Want To Do That?

What Is Blood Flow Restriction (BFR) Training?

Blood flow restriction training is the use of tourniquets either on both upper or lower extremities and can even be used on all four extremities at the same time. The cuffs are placed as proximal as possible in the groin or upper arm depending on the extremities being used. The purpose of blood flow restriction training is to improve muscle strength and hypertrophy while working at lower intensities and percentages of their one rep max. These percentages can be as low as 20-30% of a person’s one rep max which is significantly lower than typical resistance training which requires lifting 70%+ of a person’s one rep max. We will dive into both the physiology of blood flow restriction training as well as the clinical applications further in this blog post.

What Is The Physiology Behind Blood Flow Restriction Training?

Continued research is ongoing about the physiology behind BFR training as even research has begun to come out that examines the positive benefit from the use of BFR cuffs without performing any exercises indicating the huge benefits of the cellular physiology behind BFR training. There are multiple hypotheses as to why blood flow restriction training demonstrates such muscular improvements. The physiology behind BFR can be quite dense so I will do my best to lay out the information in a way that is easy to read. The first benefit found with BFR training is the faster recruitment of large motor units. A motor unit consists of a single motor neuron and all of the muscle fibers that this single motor neuron innervate. The improvement in speed of large motor unit has large implications for strength training and overall performance of both young and older populations. The next benefit seen with BFR training is the creation of a hypoxic environment. Hypoxic environment refers to an inadequate amount of oxygen at the tissue level resulting in greater metabolic and hormonal responses. These metabolic and hormonal responses include the increases in blood lactate, serum growth hormone, norepinephrine, testosterone, and cortisol concentrations. The accumulation of hydrogen ions within the muscle results in an augmented growth hormone release. This release of growth hormone was 2x as high in the BFR group as compared with controls. This growth hormone release is most important during recovery due to the increased collagen synthesis as well as in the development of new muscle cells. Lastly, BFR has been shown to stimulate the muscle protein synthesis in older males aged 70+ demonstrating the potential use of BFR in older populations to counteract sarcopenia.

Clinical Applications Of BFR

We may have lost you during the physiology aspect of the blood flow restriction training,

but now we’d like to outline the many different clinical applications of BFR training

  •  Post-Surgical – These are the patients that we typically utilize BFR training during our plans of care. Research has shown to diminish atrophy of quadriceps following ACL reconstruction and BFR has been shown to improve hypertrophy with only 20-30% of 1 rep max. We utilize BFR early on with the use of neuromuscular electrical stimulation (NMES) to improve quadriceps activation and strength. Later on, we utilize BFR with lower extremity strengthening exercises in both closed/open kinetic chain situations as well as neuromuscular control exercises such as Y balance to improve co-contraction and overall lower extremity function.
  • Tendinopathy – We like to use BFR to improve hypertrophy and strength when pain/tolerance to exercise is a limiting factor. We like to combine the use of BFR cuffs with isometrics at varying angles and eccentrics to improve overall tendon health.
  •  Hypertrophy – We also like to utilize BFR for accessory work for the athlete that is just looking to increase muscle size.
  •  Aerobic Capacity – Research has shown that low-intensity short-duration cycling combined with BFR improves both muscle hypertrophy and aerobic capacity concurrently in young men. Research has also shown to increase stroke volume, decrease heart rate, and increase VO2 max by 11% over 2 weeks of walking with BFR in collegiate basketball players. Yes, WALKING. The rehabilitation implications of BFR with walking are very promising even outside the younger population.

This is by no means an exhaustive list, rather just some of the more common reasonings for why we utilize BFR training.

Overall, the research for the use of BFR training has increased significantly with its popularity over the last decade or so. We have seen first-hand the benefits of using BFR in the rehabilitation setting and use it on a regular basis. If you have any questions regarding BFR just shoot us a message. If you’re interested in purchasing BFR cuffs for your own personal use, check out SAGA Fitness and use Promo Code: ironstandard at checkout for a 15% discount!

Sources:

 

1. Takarada Y, Takazawa H, Ishii N. Applications of vascular occlusion diminish disuse atrophy of knee extensor muscles. Med Sci Sports Exerc. 2000;32(12):2035-2039.
   
2. Takarada Y, Takazawa H, Sato Y, Takebayashi S, Tanaka Y, Ishii N. Effects of resistance exercise combined with moderate vascular occlusion on muscular function in humans. J Appl Physiol. 2000;88(6):2097-2106.
   
3. Kon M, Ikeda T, Homma T, Suzuki Y. Effects of low-intensity resistance exercise under acute systemic hypoxia on hormonal responses. J Strength Cond Res. 2012;26(3):611-617.
   
4. Park S, Kim JK, Choi HM, Kim HG, Beekley MD, Nho H. Increase in maximal oxygen uptake following 2-week walk training with blood flow occlusion in athletes. Eur J Appl Physiol. 2010;109(4):591-600.
   
5. Suga T, Okita K, Morita N, et al. Dose effect on intramuscular metabolic stress during low-intensity resistance exercise with blood flow restriction. J Appl Physiol. 2010;108(6):1563-1567.
   
6. Ozaki H, Sakamaki M, Yasuda T, et al. Increases in thigh muscle volume and strength by walk training with leg blood flow reduction in older participants. J Gerontol A Biol Sci Med Sci. 2011;66(3):257-263.
   
7. Loenneke JP, Wilson JM, Marín PJ, Zourdos MC, Bemben MG. Low intensity blood flow restriction training: a meta-analysis. Eur J Appl Physiol. 2012;112(5):1849-1859.
   
8. Kubota A, Sakuraba K, Koh S, Ogura Y, Tamura Y. Blood flow restriction by low compressive force prevents disuse muscular weakness. J Sci Med Sport. 2011;14(2):95-99.
   
9. Fujita S, Abe T, Drummond MJ, et al. Blood flow restriction during low-intensity resistance exercise increases S6K1 phosphorylation and muscle protein synthesis. J Appl Physiol. 2007;103(3):903-910.
   
10. Fry CS, Glynn EL, Drummond MJ, et al. Blood flow restriction exercise stimulates mTORC1 signaling and muscle protein synthesis in older men. J Appl Physiol. 2010;108(5):1199-1209.