Effects of exercise intensity and occlusion pressure after 12 weeks of resistance training with blood-flow restriction

TLDR: BFRT protocols benefit from higher occlusion pressure (80 %) when exercising at very low intensities when considering muscle strength, and conventional high-intensity resistance training (RT) protocols seem less effective than high- intensity RT.

Abstract: We compared the effects of different protocols of blood-flow restriction training (BFRT) with different occlusion pressures and/or exercise intensities on muscle mass and strength We also compared BFRT protocols with conventional high-intensity resistance training (RT) Twenty-six subjects had each leg allocated to two of five protocols BFRT protocols were performed at either 20 or 40 % 1-RM with either 40 or 80 % occlusion pressure: BFRT20/40, BFRT20/80, BFRT40/40, and BFRT40/80 Conventional RT was performed at 80 % 1-RM (RT80) without blood-flow restriction Maximum dynamic strength (1-RM) and quadriceps cross-sectional area (CSA) were assessed at baseline and after 12 weeks Regarding muscle mass, increasing occlusion pressure was effective only at very low intensity (BFRT20/40 078 % vs BFRT20/80 322 %) No additional increase was observed at higher intensities (BFRT40/40 445 % vs BFRT40/80 530 %), with no difference between the latter protocols and RT80 (590 %) Exercise intensity played a role in CSA when comparing groups with similar occlusion pressure Muscle strength was similarly increased among BFRT groups (~1210 %) but to a lesser extent than RT80 (2160 %) In conclusion, BFRT protocols benefit from higher occlusion pressure (80 %) when exercising at very low intensities Conversely, occlusion pressure seems secondary to exercise intensity in more intense (40 % 1-RM) BFRT protocols Finally, when considering muscle strength, BFRT protocols seem less effective than high-intensity RT