Perceptual and arterial occlusion responses to very low load blood flow restricted exercise performed to volitional failure

Abstract

High load exercise will likely be perceived more favourably than lower load exercise to volitional failure; however, those who are incapable or unwilling to lift heavier loads may use blood flow restriction to help reduce the volume needed to reach volitional failure, although this will likely increase discomfort.

Is there rationale for the cuff pressures prescribed for blood flow restriction exercise? A systematic review

“…Other populations included resistance‐trained adults, adults with musculoskeletal or soft tissue injuries, older adults, or adults with hypertension. There were far more studies (26 of 52) examining only male participants, 17,24,25,30,32‐38,41‐43,46,48,50‐59 compared with just 8 of 52 examining only female participants, 40,49,60‐65 leaving 18 studies examining both of these genders 8,19,20,39,44,45,47,66‐75 …”

“…Sixteen of the 52 included studies applied multiple different cuff pressures as a means of comparing acute responses or chronic adaptations to different applied pressures 17,20,31,32,36,39,43,44,48,54,67,68,70,72,73,75 . Among the remaining 36 studies using a single individualized pressure for their application of BFR, 13 studies used 80% AOP/LOP, 24,37,40,49,50,57,61,62,64‐66,71,74 7 studies used 60% AOP/LOP, 8,33,34,38,46,52,56 5 studies used 50% AOP/LOP, 25,41,42,59,60 4 studies used 100% AOP, 47,51,58,63 4 studies used 40% AOP/LOP, 19,30,45,69 and 3 studies used 30% AOP 35,53,55 .…”

“…The posture in which assessment of occlusion pressure was conducted was not reported in 15 of the 52 included studies 24,30,32,34,35,43,47,49,51,53,58,61‐63,74 . Among those reporting participant posture during assessment, supine 17,36,37,40,42,48,50,54,56,57,59,64,65 or standing 8,19,20,31,41,44,46,52,69,70,72,73,75 were each chosen in 13 studies, and sitting was used in 11 studies 25,33,38,39,45,55,60,66‐68,71 …”

“…Seventeen of the included studies reported using a “standard sphygmomanometer” to apply BFR, rather than a dynamic pneumatically regulated system. The pattern of inflation was described in 43 out of the 52 included studies, with 38 studies using continuous inflation across the full duration of exercise (multiple sets and repetitions), 8,17,25,31‐36,38,39,42,43,46‐50,52‐54,56‐65,67‐71,74 only 3 studies using an intermittent inflation pattern whereby cuffs were deflated between sets of each exercise, 37,51,55 and 2 studies including both continuous and intermittent inflation patterns in separate experimental groups 24,40 …”

“…This would also apply to generally sedentary populations, who may not have been exposed to the level of exertion intrinsically required during exercise, and thus may be deterred with unnecessarily elevated discomfort. Conversely, in healthy, physically active populations, particularly those that are resistance trained, the most commonly examined population among the included studies in this review, 17,19,20,24,25,31‐52,55,57,58,67‐70,72,73,75 maximizing the physiological benefits of BFR may be preferable, despite potentially elevated discomfort. Regular exercise has also been shown to have a chronic‐acute analgesic effect and reduce nociceptor excitability, suggesting that physically active populations may be less prone to exercise‐induced discomfort 79,80 .…”