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Updated: Aug 31, 2025

Isometric and Eccentric Force Generation Assessment of Skeletal Muscles Isolated from Murine Models of Muscular Dystrophies
Published on: January 31, 2013
Differences Between Pullover and Pulldown Exercises on Maximal Isometric Force and Myoelectric Activity in
Luis Felipe M Teixeira1, Willy A Gomes2,3, Josinaldo J DA Silva2
1Department of Physical Education, Campinas State University, Campinas, BRAZIL.
Abstract:
The aim of the present study was to compare the myoelectric activation and peak force (PF) between pullover (PO) and pulldown (PW) exercises in different shoulder joint positions during maximal isometric contractions (0o, 45o, 90o, 135o, and 180°). Fifteen young, healthy, resistance-trained men were recruited. The participants performed three maximal voluntary isometric contractions for each exercise at five shoulder joint positions. The myoelectric activation (iEMG) from pectoralis major (PM); latissimus dorsi (LD); posterior deltoid (PD), and PF were measured. For PF, there were significant main effects for exercise and joint positions (p < 0.001). For iEMG PM, there was significant a main effect for joint positions (p < 0.001). There was a significant interaction between exercises and joint positions (p < 0.001). For iEMG LD, there was a significant main effect for joint positions (p < 0.001). There was no significant interaction between exercises and joint positions. For iEMG PD, there was a significant main effect for joint positions (p < 0.001). There was no significant interaction between exercises and joint positions. For RPE, there were no significant differences between exercises and joint positions. The study concludes that specific shoulder joint positions affect PF production and iEMG during both exercises. RPE was not affected.
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