Lower occlusion pressure during resistance exercise with blood-flow restriction promotes lower pain and perception of exercise compared to higher occlusion pressure when the total training volume is equalized

Low-intensity resistance exercise with blood-flow restriction (BFR) promotes similar adaptations to high-intensity resistance exercise (HI-RE). Interestingly, BFR has been demonstrated to be effective for a wide range of occlusion pressures. However, the occlusion pressure magnitude may alter the psychophysiological stress related to BFR as measured by rating of perceived exertion scale (RPE) and rating of pain. We aimed to compare the RPE and pain levels across different magnitudes of occlusion pressures, promoting new knowledge regarding occlusion pressure on stress related to BFR. All BFR protocols ranging between 40% and 80% of total arterial occlusion (BFR40, BFR50, BFR60, BFR70, and BFR80) were compared to HI-RE in 12 participants using a randomized and crossover design 72 h apart. BFR protocols and HI-RE were performed with 30% and 80% of one- repetition maximum (1RM) test value, respectively. RPE and pain levels were measured before exercise and immediately after each set. BFR protocols (i.e., BFR40 and BFR50) presented overall lower RPE response compared to higher-pressure BFR (i.e., BFR70 and BFR80) and HI-RE conditions. For pain levels, low-pressure BFRs (i.e., BFR40 and BFR50), and HI-RE showed lower values than high-pressure BFR protocols (i.e., BFR60, BFR70, and BFR80). In conclusion, low-pressure BFR protocols promote lower RPE and pain compared to high-pressure BFR protocols (between 60% and 80% of occlusion pressure), when total training volume (TTV) is equalized. In addition, HI-RE promotes similar levels of pain, but higher RPE than low-pressure BFR, probably due to the higher TTV.