The post-activation performance effects four minutes after back squatting with blood flow restriction or followed ischemic preconditioning in weak and strong participants

Purpose This study investigated the post-activation performance enhancement (PAPE) effects of back squats (BS) with blood flow restriction (BFR) or after ischemic preconditioning (IPC) and compared it between strong and weak participants. Methods Fourteen male participants with at least one year of resistance training experience (average ± SD age: 23.6 ± 3.5 years, height: 1.8 ± 0.1 m, body mass–BM: 82.9 ± 13.4 kg) were introduced to a familiarization session with the countermovement jump (CMJ) and BS one-repetition maximum assessment (1-RM BS: 149.8 ± 36.8 kg; 1-RM BS/BM: 1.8 ± 0.4). This was followed by six visits for different CAs: warm-up, BS, BS with BFR (BS-BFR), BS-BFR sham, BS after IPC (BS-IPC), and BS-IPC sham. At the beginning of each visit, participants were introduced to a standardized warm-up for 10 min followed by three CMJs, the CA of the day, and, after 4 min, three CMJs. Participants who presented a relative 1-RM BS equal or above 1.75 were classified as strong ( n = 8). Changes in CMJ height were compared by a two-way repeated measures ANOVA for overall, strong and weak participants with Bonferroni post-hoc. Results A significant interaction effect was observed in CMJ height for overall participants (F = 3.19; p = 0.012; ղ 2 p = 0.197); however, post-hoc analyses revealed no significant PAPE effect. Likewise, no significant increases in CMJ performance were observed among either the strong participants (F = 1.098; p = 0.379; ղ 2 p = 0.136) or the weak participants (F = 2.165; p = 0.090; ղ 2 p = 0.302). Conclusions The present study showed that no PAPE is observed 4 min after BS and BS combined with BFR or IPC. Therefore, athletes and coaches should avoid using BFR or IPC if the aim is to evoke short-term PAPE.