Acute neuromuscular and metabolic responses to complex training with blood flow restriction: effects of arterial occlusion pressure on post-activation performance enhancement

Purpose This study examined the acute effects of complex training (CT) with blood flow restriction (BFR) on countermovement jump (CMJ) performance, lower - limb muscle activation, and blood lactate (BLa) concentration in trained male collegiate athletes. It also aimed to identify the arterial occlusion pressure (AOP) level and recovery time window that produced the most favorable post - activation performance enhancement (PAPE) response. Methods Using a randomized crossover design, twelve trained male collegiate athletes completed four experimental conditions: traditional CT and CT - BFR at 60%, 70%, and 80% AOP. CMJ performance (VJH: vertical jump height and RPP: relative peak power), muscle activation (RMS: root mean square and MF: median frequency), and BLa were assessed before the intervention and at 4, 8, 12, and 16 min following each protocol. Results Traditional CT also induced significant changes in selected variables at specific recovery time points. However, the 70% AOP condition showed more consistent improvements among the tested conditions. Under 70% AOP, CMJ performance improved at 8 min, with significant increases in VJH ( p < 0.05, ES = 0.37) and RPP ( p < 0.05, ES = 0.94). RPP also remained elevated at 12 min ( p < 0.05, ES = 0.77). This condition also showed more consistent sEMG responses, with increased RMS in the RF, VM, VL, and BF at 8 min, and changes in the VM and VL at 12 min ( p < 0.05). MF changes were mainly observed in the VM and VL. In contrast, the 60% and 80% AOP conditions showed less consistent improvements in CMJ performance and muscle activation. BLa showed a significant time effect and AOP × time interaction, increasing markedly after the intervention, peaking at 4 min, and then progressively declining during recovery ( p < 0.01). Conclusion CT-BFR at 70% AOP showed a relatively favorable acute response among the tested conditions, especially for CMJ performance and thigh muscle activation during the 8–12 min recovery window. These findings provide preliminary evidence that 70% AOP may be a potentially suitable pressure level for CT - BFR based on the acute responses observed during PAPE based warm - up protocols.