Task-specific neural adaptations to isoinertial resistance training

This study aimed to delineate the contribution of adaptations in agonist, antagonist and stabiliser muscle activation to changes in isometric and isoinertial lifting strength after short-term isoinertial resistance training (RT). Following familiarisation, 45 men (23.2±2.8 yrs) performed maximal isometric and isoinertial strength tests of the elbow flexors of their dominant arm before and after three weeks of isoinertial RT. During these tasks surface EMG amplitude was recorded from the agonist (biceps brachii short and long heads), antagonist (triceps brachii lateral head) and stabiliser (anterior deltoid, pectoralis major) muscles and normalised to either Mmax (agonists) or to maximum EMG during relevant reference tasks (antagonist, stabilisers). After training there was more than a two-fold greater increase in training task specific isoinertial than isometric strength (17 vs. 7%). There were also task specific adaptations in agonist EMG, with greater increases during the isoinertial than isometric strength task (ANOVA, training x task, P=0.005). A novel finding of this study was that training increased stabiliser muscle activation during all the elbow flexion strength tasks (P