Journal of Applied Sports Sciences 10(1): 127-136, doi: 10.37393/JASS.2026.10.01.10
Impact of shoulder abduction angle on peak force and myoelectric activity during maximal isometric bench press in resistance-trained men
Paulo Marchetti‡, Colin Stas‡, Charles Lopes§, Estevão Monteiro|‡ Resistance Training Laboratory, Department of Kinesiology, California State University, Northridge, United States of America§ School of Physical Education, Pontifi cal Catholic University of Campinas, Campinas, Brazil| Graduate Program in Rehabilitation Science, Augusto Motta University Center, Rio de Janeiro, Brazil
Corresponding author: Paulo Marchetti ( dr.pmarchetti@gmail.com ) Academic editor: Valentin Panayotov © Paulo Marchetti, Colin Stas, Charles Lopes, Estevão Monteiro. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY-NC-SA 4.0), which permits to copy and distribute the article for non-commercial purposes, and the original author and source are credited. Adapted content must be distributed under the same license Citation:
Marchetti P, Stas C, Lopes C, Monteiro E (2026) Impact of shoulder abduction angle on peak force and myoelectric activity during maximal isometric bench press in resistance-trained men. Journal of Applied Sports Sciences 10(1): 127-136. https://doi.org/10.37393/JASS.2026.10.01.10 |  |
Abstract
The purpose of this study was to investigate the infl uence of shoulder abduction positions (45° vs. 90°) on peak force (PF) production and myoelectric activity (sEMG) of the upper and lower pectoralis major (UPM, LPM), anterior deltoid (AD), and long head of the triceps brachii (TB) during maximal isometric bench press in resistance-trained men. Twelve young, resistance-trained men (age: 24.7 ± 4.2 years) participated in a quasi-experimental, within-subject study. Each subject performed three maximal isometric bench press contractions for both shoulder abduction positions, during which PF and sEMG (UPM, LPM, AD, and TB) were measured. Statistical analyses included paired t-tests for PF and two-way ANOVA for sEMG. Results showed no signifi cant diff erence in PF between 45° and 90° shoulder abduction positions. For sEMG, post hoc analyses revealed signifi cant diff erences between muscles within each shoulder position: at 45°, AD vs. UPM (Δ% = 41.5%), AD vs. LPM (Δ% = 65.4%), and UPM vs. LPM (Δ% = 40.8%); at 90°, AD vs. LPM (Δ% = 61.9%) and UPM vs. LPM (Δ% = 41.2%). These fi ndings suggest that shoulder abduction position (45° vs. 90°) does not aff ect maximal isometric force production or substantially alter myoelectric activation patterns in resistance-trained men.
Keywords
Resistance Exercise; Shoulder Joint; Electromyography