Effects of passive blood flow restriction on muscle function following exercise-induced muscle damage in...

This investigation examined the effects of passive blood flow restriction (pBFR) on indices of exercise-induced muscle damage (EIMD) in recreationally active males. Fifteen males completed six consecutive visits (±2 hours). Participants completed 3 × 25 maximal, unilateral, isokinetic (60°·s^-1), concentric-eccentric leg extensions on both legs. Each leg was randomly assigned to receive pBFR (80% arterial occlusion pressure) or sham (20 mmHg) at 0, 24, 48, 72, and 96 hours post-EIMD. Perceived muscle soreness, range of motion (ROM), pain pressure threshold (PPT), concentric peak torque (CPT), and maximal voluntary isometric contraction (MVIC) torque were assessed and analyzed using separate linear mixed-effects models. Perceived muscle soreness increased at 24 hours (mean difference [mean_diff] = 4.9 au; p < 0.001) and recovered by 96 hours (p = 0.482), with no differences between conditions (p = 0.450). ROM (mean_diff = -3.1°; p = 0.040), PPT (mean_diff = -1.63 kgf; p < 0.001), CPT (mean_diff = -27.7 Nm; p < 0.001), and MVIC torque (mean_diff = -30.8 Nm; p < 0.001) decreased at 24 hours, with recovery occurring between 48-96 hours. Condition-specific differences were observed for ROM (mean_diff = 2.5°; p < 0.001), PPT (mean_diff = 0.49 kgf; p = 0.005), CPT (mean_diff = 6.2 Nm; p = 0.020), and MVIC torque (mean_diff = 7.1 Nm; p = 0.044), which were greater in pBFR than sham. These findings suggested that pBFR may reduce impairments in ROM, PPT, CPT, and MVIC torque following EIMD, despite a similar recovery trajectory between conditions.