The Amplitude-Time Characteristics of Post-Activation Performance Enhancement With Blood Flow Restriction: A...

Blood flow restriction (BFR) is effective for improving long-term sports performance, but its impact on post-activation performance enhancement (PAPE) remains inconclusive. This study aimed to (1) examine the amplitude-time characteristics of PAPE through within-group comparisons of equal-intensity conditioning activities (CAs) performed under different BFR pressures; and (2) compare, using between-group analyses, the effects of CA + BFR vs. CA-only or passive rest, low-intensity CA + BFR vs. high-intensity CA, and BFR at rest vs. passive rest alone on performance outcomes, power output, and rate of force development (RFD) across different recovery intervals. A systematic search was conducted in three English-language and one Chinese database. Included studies examined at least one of four predefined comparisons and reported outcomes related to performance (e.g., jump, sprint, and bench throw), power output (e.g., peak, mean, relative peak, and relative mean power), or RFD. Data were pooled using cluster-robust variance estimation and a three-level mixed-effects model with small-sample corrections. Meta-regression was performed to examine the relationship between PAPE and recovery time. The effect size was expressed as the standardized mean change (SMC) for within-group comparisons and as the standardized mean difference (SMD) for between-group comparisons. Thirteen studies (212 participants) met the inclusion criteria. Within-group comparisons showed that arterial occlusion pressures (AOP) of 30%, 50%, 60%, 70%, and 80% imposed during a 30% 1-repetition maximum (1-RM) CA enhanced performance at 3-12 min post-intervention, with SMCs of 0.56, 0.81, 0.64, 0.41, and 0.11. Peak gains occurred at 4 min (SMC = 0.77; 95% CI 0.13-1.42), 5 min (SMC = 1.29; 95% CI 0.61-1.97), 5 min (SMC = 0.72; 95% CI -5.40-6.02), 8 min (SMC = 1.02; 95% CI 0.32-1.72), and 12 min (SMC = 0.74; 95% CI 0.20-1.24), respectively. Between-group comparisons revealed small but significant improvements in performance (SMD = 0.21; 95% CI 0.01-0.40) and power output (SMD = 0.15; 95% CI 0.02-0.28) but not RFD (SMD = 0.11; 95% CI -0.08-0.30) for CA + BFR compared to control. The other three models had no significant effects on any outcomes. Recovery time was an important moderator across all comparisons, resulting in five distinct PAPE-recovery time patterns for equal-intensity CAs performed under different BFR pressures. Five distinct PAPE-recovery time patterns emerged, with specific CA intensity and BFR pressure (30%-80%) combinations producing unique response profiles. Incorporating BFR into CAs or replacing high-intensity CAs with low-intensity ones may provide a practical strategy for acutely enhancing performance and power output. Preliminary evidence suggests that combining 50% AOP with 30%-50% 1-RM squats or leg press may enhance jump performance in the 3-12 min post-CA window; however, protocol selection should be tailored according to individual PAPE response models.