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Updated: Oct 11, 2025

Non-invasive Assessments of Subjective and Objective Recovery Characteristics Following an Exhaustive Jump Protocol
Published on: June 8, 2017
Comparison of post-activation performance enhancement (PAPE) after isometric and isotonic exercise on vertical jump
Salvador Vargas-Molina1,2, Ulises Salgado-Ramírez1, Iván Chulvi-Medrano3
1Exercise Physiology Laboratory, Department of Physical Education and Sports, Faculty of Medicine, University of Malaga, Malaga, Spain.
Purpose:
This study aimed to compare the post-activation performance enhancement (PAPE) induced by isometric and isotonic exercise on vertical jump performance.
Methods:
18 healthy trained men (25.8±2.7 years; 78.4±8.2 kg; 175.7±6.1 cm; 25.4±1.8 BMI; 126.72±10.8 kg squat 1-RM) volunteered for this study. They randomly performed two different PAPE protocols: Isotonic squats (ISOTS), which consisted of 2 sets of 3 repetitions at 75% of one-maximum repetition (1-RM); and isometric squats (ISOMS), which consisted of 2 sets of 4 seconds of submaximal (75% of 1-RM) isometric contraction at 90°-knee flexion. Countermovement jump (CMJ) height was tested at baseline and 4 minutes after each conditioning set.
Results:
CMJ height significantly increased after set 1 in both PAPE protocols (ISOMS: p <0.001; ES = 0.34; ISOTS: p <0.001; ES = 0.24), with respect to the baseline jump. However, after set 2 no significant changes in CMJ height were observed for any protocol (ISOMS: p = 0.162; ES = 0.11; ISOTS: p = 0.976; ES = 0.06). No significant differences (p>0.05) were found between both isometric and isotonic exercise conditions.
Conclusions:
Despite both protocols showed similar PAPE effects on CMJ height after set 1, none of the protocols demonstrated greater efficacy in increasing subsequent performance in healthy trained men.
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