Influence of back squat eccentric tempo on countermovement jump performance and evaluation of PAPE detection thresholds.

The aim of this study was to: (a) compare potentiation effect of three eccentric phase duration on countermovement jump (CMJ); (b) evaluate approaches for verification of post activation performance enhancement (PAPE); (c) verify whether muscle saturation and time of reoxygenation are relevant to explain PAPE. Eighteen men with experience in strength training completed four sessions. The first one included one repetition maximum testing (1RM) and familiarization. The remaining focused on potentiation protocol which was four repetitions with 80% 1RM at given tempo, 2/0/X/0 (FAST), 4/0/X/0 (MED), 6/0/X/0 (SLOW) respectively. Before and after conditioning activity (CA) CMJ was conducted. During CA barbell velocity and muscle saturation was monitored, There were no changes in CMJ height at 1, 4 and 8 min (F(3153) = 0.65, p = 0.58) in each condition. However, for an approach with changes between pre-post analysis showed significant increases in the CMJ height for SLOW (3.5%, p < 0.05) and MED (4.2%, p < 0.01) The smallest worthwhile change analysis showed the highest proportion of participants exhibiting a PAPE effect. Muscle saturation did not differ tempo and time of reoxygenation has not any relationship on magnitude of PAPE. Methodological approach has a large influence on the examination PAPE. Muscle saturation does not provide explanation of PAPE.