The Effects of Blood Flow Restriction on Upper-Body Musculature Located Distal and Proximal to Applied Pressure.

Abstract

Blood flow restriction (BFR) training has been shown to increase muscle size and strength when combined with low-load [20-30% one-repetition maximum (1RM)] resistance training in the lower body. Fewer studies have examined low-load BFR training in combination with upper body exercise, which may differ as some musculature cannot be directly restricted by the BFR stimulus (chest, shoulders). The objective of this study was to examine muscle adaptations occurring in the upper body in response to low-load BFR training. Google Scholar, PubMed, and SPORTDiscus were searched through July 2015 using the key phrases 'blood flow restriction training', 'occlusion resistance training', and 'KAATSU'. Upper body training studies implementing the BFR stimulus and providing a pre and post measure of muscle size and/or strength were included. A total of 19 articles met the inclusion criteria for this review. The effectiveness of low-load BFR training appears to be minimally impacted by alterations to the intensity and restrictive pressures used; however, the ability to quantitatively analyze our results was limited by unstandardized protocols. Low-load BFR training increased muscle size and strength in limbs located proximal (chest, shoulders) and distal (biceps, triceps) to the restrictive stimulus; while volume-matched exercise in the absence of BFR did not elicit beneficial muscle adaptations. Some of the musculature in the upper body cannot be directly restricted by the application of BFR. Despite this, increases in muscle size and strength were observed in muscles placed under direct and indirect BFR.