Examination of the comfort and pain experienced with blood flow restriction training during post-surgery rehabilitation of anterior cruciate ligament reconstruction patients: A UK National Health Service trial

Abstract

Objective Examine the comfort and pain experienced with blow flow restriction resistance training (BFR-RT) compared to standard care heavy load resistance training (HL-RT) during anterior cruciate ligament reconstruction (ACLR) patient rehabilitation. Design Randomised controlled trial.

Low intensity blood flow restriction exercise: Rationale for a hypoalgesia effect

“…Elevations in peripheral blood beta-endorphin concentrations have been reported in humans 6 following exercise [7,64], which is thought to be caused by stimulation of group III and IV primary afferents in the contracting muscle. This is turn activates the opioid system [7] and modulates pain via spinal and/or supraspinal inhibitory mechanisms [46], which may drive pain desensitisation in non-exercising and remote muscles [10]. Several studies reporting attenuation of EIH following administration of an opioid antagonist such as naloxone or naltrexone in humans [65,66] and animals [67] support the role of the opioid system in EIH [1].…”

“…For example, beta-endorphin is produced in the PNS and CNS in response to both pain and exercise. This is believed to be caused by stimulation of group III and IV primary afferents in the contracting muscle, which then activates the opioid system [7] and modulates pain via spinal and/or supraspinal inhibitory mechanisms [46]. Similarly, endocannabinoids are released from their synthesising cells in response to physical stress [49].…”

“…For load compromised and rehabilitating populations with chronic pain that cannot withstand high intensity exercise or low intensity exercise to failure, BFR exercise would therefore have a dual effect for pain and other adaptations. For example, BFR exercise has recently been shown to improve pain reduction and physical function to a greater extent than heavy load resistance training in individuals with rheumatoid arthritis [45] and following surgery for ligament repair [46].…”

Comparison of Blood Flow Restriction Training versus Non-Occlusive Training in Patients with Anterior Cruciate Ligament Reconstruction or Knee Osteoarthritis: A Systematic Review

“…All studies included in the review were RCTs [25][26][27][28][29][30][31][32][33][34] published from 2003 onwards. It should be noted that the studies from Hughes et al [33] 2018 and Hughes et al [34] 2019 are two reports from the same study.…”

“…All studies included in the review were RCTs [25][26][27][28][29][30][31][32][33][34] published from 2003 onwards. It should be noted that the studies from Hughes et al [33] 2018 and Hughes et al [34] 2019 are two reports from the same study. Two studies were conducted in Brazil [25,29], four in the USA [26][27][28]30], two in the UK [33,34], one in Norway [31] and one in Japan [32].…”