#carefulinterventionselection

Blood flow restriction (BFR) with use of a cuff is a way to promote muscle hypertrophy while exercising at a low intensity load. Many studies have found that there is a benefit to using BFR while exercising, however there is not a specific protocol for its use. One study found that in recreational athletes ages 20-40 when BFR was used in combination with low load exercise (30% of 1 rep max) there was a significant increase in muscle strength both proximally and distal to the cuff compared to a control group that only completed low load exercises (1).  When relating these results to clinical practice it is important to remember that many athletes who get injured are not allowed to return to high load exercises early on in their rehabilitation. This technique may be an additional option to promote strength gains allowing for quicker return to activities.

Blood flow restriction is not only being suggested for athletes but other patient populations where high load exercises may not be safe to participate in. The elderly are a great example of someone who may benefit from BFR. Cook et. al. compared the strength gains of patients over 65 who participated in either a high resistance exercise program (70% of a 1 rep max) or a low resistance program (30-50% of 1RM) in combination with BFR (2). At the conclusion of this 12 week study researchers found that gains in strength of the low resistance BFR group were comparable to the strength gains of the high resistance group (2).

Increases in muscle strength and mass with use of BFR have also been studied in patients with signs of knee osteoarthritis. Segal et. al. found that when performing low resistance exercises (30% of 1RM) with BFR osteoarthritis patients had significant strength gains in knee extensor strength and 1 rep max when compared to a control group that only performed low load exercises (3). Another important finding was that the combination of BFR and low load exercises did not negatively impact knee pain (3).

Although these studies show that BFR can be effective in different populations it is important to recognize when this method is contraindicated. Some of the patients that were excluded from participating in the studies had past medical histories that included peripheral artery disease, cardiac conditions, DVT, neuromuscular conditions, stroke, cancer, hypertension, stroke or the need for supplemental oxygen (2,3).  In addition of medical contraindications it is worth noting that this technique may not be appropriate for all healthy individuals. There may be psychological factors like anxiety or patient beliefs/values that would cause more harm than benefit.

Blood flow restriction could be beneficial to many patients where high load exercise is not appropriate. There is still more research to be completed for a proper protocol to be in place to ensure safety of the intervention. If used in the clinic all possible contraindications should be considered and the application should be done conservatively so that further damage to a patient is not done.

    References: (130 Words)

1-Bowman, E. N., Elshaar, R., Milligan, H., Jue, G., Mohr, K., Brown, P., Watanabe, D. M., & Limpisvasti, O. (2019). Proximal, Distal, and Contralateral Effects of Blood Flow Restriction Training on the Lower Extremities: A Randomized Controlled Trial. Sports health, 11(2), 149–156. https://doi-org.proxy.kumc.edu/10.1177/1941738118821929

2-Cook, S. B., LaRoche, D. P., Villa, M. R., Barile, H., & Manini, T. M. (2017). Blood flow restricted resistance training in older adults at risk of mobility limitations. Experimental gerontology, 99, 138–145. https://doi-org.proxy.kumc.edu/10.1016/j.exger.2017.10.004