Conrado de Freitas, M, Rossi, FE, Colognesi, LA, de Oliveira, JVNS, Zanchi, NE, Lira, FS, Cholewa, JM, and Gobbo, LA. Postactivation potentiation improves acute resistance exercise performance and muscular force in trained men. J Strength Cond Res XX(X): 000–000, 2018—The purpose of this study was to investigate the effects of heavy back squat (90% one repetition maximum [1RM]) postactivation potentiation (PAP) on acute resistance exercise performance and force production in recreationally trained men, and to verify the relationship between maximal strength and the PAP response. Ten resistance-trained men randomly completed 4 experimental trials: (a) back squats without PAP (No-PAP), (b) back squats with PAP, (c) maximum voluntary isometric contraction (MVIC) of the quadriceps without PAP, and (d) MVIC with PAP. Back squats were performed with 4 sets at 70% of 1 RM with 2 minutes of rest interval. The number of squats repetitions performed was recorded for each set, and a total number of repetitions were calculated to analyze performance. Maximum voluntary isometric contraction was measured using electronic dynamometer, and the peak force and mean force were recorded. Blood lactate concentration was analyzed presquat and postsquat exercise. Repetitions performed in the first set was significantly (p < 0.001) greater in the PAP condition (22.00 ± 5.14) compared with No-PAP (15.50 ± 5.10), which resulted in significantly (p = 0.001) more total repetitions performed in the PAP (56.20 ± 17.3) condition compared with No-PAP (48.80 ± 14.5). Maximum voluntary isometric contraction peak was higher in PAP than in No-PAP (PAP = 765.7 ± 147.8 vs. No-PAP = 696.8 ± 131.5 N, p = 0.006). No significant correlations were observed between back squat 1RM relative to body mass and the PAP response in squat and MVIC. There were no significant differences in lactate concentration between conditions. In conclusion, PAP resulting from a heavy load prior back squat exercise improved total volume during resistance exercise. In addition, PAP was effective to increase force production during MVIC, but there was no relationship between relative 1RM values and the PAP response in trained men.
1Skeletal Muscle Assessment Laboratory (LABSIM), Department of Physical Education, School of Technology and Sciences, São Paulo State University (UNESP), Presidente Prudente, Brazil;
2Department of Physical Education, Post Graduation Program in Movement Sciences, School of Technology and Sciences, São Paulo State University (UNESP), Presidente Prudente, Brazil;
3Department of Nutrition, University of Western São Paulo (UNOESTE), Presidente Prudente, Brazil;
4Department of Physical Education, Immunometabolism of Skeletal Muscle and Exercise Research Group, Federal University of Piauí (UFPI), Teresina, Brazil;
5Exercise and Immunometabolism Research Group, Department of Physical Education, São Paulo State University (UNESP), Presidente Prudente, Brazil;
6Department of Physical Education, Laboratory of Cellular and Molecular Biology of Skeletal Muscle (LABCEMME), São Luis, Brazil; and
7Department of Kinesiology, Coastal Carolina University, Conway, South Carolina
Address correspondence to Marcelo Conrado de Freitas, firstname.lastname@example.org.