The analgesic effect of BFR - a way to reduce pain in tendons and joints

One of the many comments from users of blood flow restriction training is how they experience a decrease in pain whilst using the cuffs.  One colleague who had quite bad knees in fact commented that he experienced pain relief for up to 24 hours after using the SRT cuffs. For those who like to exercise, the use of BFR training provides a valuable avenue for people who typically suffer from tendon or joint pain.  

For this blog I have reviewed a few papers highlighting the positive acute and longitudinal pain reduction effects whilst using BFR training. Enjoy the read and please comment below if you can share your experiences whilst using BFR training.  For your convenience this article is also available as a downloadable PDF in the Resources section.

Blood flow restriction (BFR) training is traditionally known for positive muscular adaptions using loads of 20-30% of one repetition maximum (1RM). However to develop muscle strength or hypertrophy loads at 70-85% 1RM are prescribed(2). However the mechanical stress associated with lifting loads of between 70-85% produces high loads on the joints and associated structures. In people who have tendon or joint issues, they experience uncomfortable levels of pain during movement and exercise. Therefore they often reduce resistance to not provoke symptoms despite these loads being not of enough stimulus to maximize muscle hypertrophy and strength gains (1).

BFR combined with low-load exercise has been demonstrated to induce muscle morphological changes, improve strength and attenuate muscle atrophy after immobilization (6). The addition of BFR to an exercise program has demonstrated an additional benefit in the improvement in pain levels (3–5). Korakakis et al (2017) reported that a single BFR-exercise bout immediately reduced anterior knee pain with the effect sustained for at least 45min. BFR pressure was set at 80% of arterial occlusion (AO) and the protocol included four sets of low-load open kinetic chain knee extensions and load was individualized according to tolerance. Significant effects were found with greater pain relief immediate after BFR in two different conditions of bilateral leg squat, single-leg squat and step-down test (p<.017).

Giles et al (2018) compared the effect of a standard quadriceps-strengthening program to low load BFR over an 8-week training period in people (n=64) with patellofemoral pain (PFP).

In both groups the range of motions were selected to minimize patellofemoral joint load. No statistically significant difference in change was found between groups over 8 weeks in worst pain or Kujala Patellofemoral Score. There was a 93% greater reduction in pain with ADL (p=.02) over 8 weeks in the BFR group relative to the standardised quadriceps-strengthening group. A 49% greater improvement in knee extensor torque in the BFR group was also observed (p=0.07).

Ferraz et al (2017) investigated the effects of a 12-week BFR training intervention in 48 females with knee osteoarthritis (OA) utilizing three different exercise protocols (Table 2).

Similar within-group increases were observed in leg press (26% & 33%, p<.001), knee extension 1RM (23% & 22%, p<.001) and quadriceps CSA (7% & 8%, p<.001) in BFR and HI-RT respectively and these were significantly greater (p<0.5) than those of LI-RT. BFR training also reported significant improvements (p<.05) in a physical function and pain score (WOMAC) test.

 These studies highlight the short and longer-term effect of performing BFR low load exercises to increase quadriceps strength and reduce knee pain. This is especially useful for people who cannot tolerate the load of a standard strengthening program due to pain. With the ability to also use BFR for the upper body, this concept may pose a benefit for upper body BFR training targeting those who may experience either elbow or shoulder pain.

References:

1. Chiu, J.K.W., Wong, Y.M., Yung, P.S.H., and Ng, G.Y.F. The effects of quadriceps strengthening on pain, function, and patellofemoral joint contact area in persons with patellofemoral pain. American Journal Of Physical Medicine And Rehabilitation. 91: 98–106, 2012.
2. Communications, S. American College of Sports Medicine position stand. Progression models in resistance training for healthy adults. Medicine And Science In Sports And Exercise. 41: 687–708, 2009.
3. Ferraz, R.B., Gualano, B., Rodrigues, R., Kurimori, C.O., Fuller, R., Lima, F.R., et al. Benefits of Resistance Training with Blood Flow Restriction in Knee Osteoarthritis. Medicine & Science In Sports & Exercise. 1, 2017.
4. Giles, L., Webster, K.E., McClelland, J., and Cook, J.L. British Journal of Sports Medicine. , 2017.
5. Korakakis, V., Whiteley, R., and Epameinontidis, K. Blood flow restriction-induced analgesia in patients with anterior knee pain. Journal Of Science And Medicine In Sport. 20: e100, 2017.
6. Scott, B.R., Loenneke, J.P., Slattery, K.M., and Dascombe, B.J. Exercise with Blood Flow Restriction: An Updated Evidence-Based Approach for Enhanced Muscular Development. Sports Medicine. 313–325, 2014.