The effects of muscle action, repetition duration, and loading strategies of a whole-body, progressive resistance training programme on muscular performance and body composition in trained males and females

Research has produced equivocal results with regard to eccentric (ECC) only compared with traditional concentric/eccentric resistance training (RT). When considered in relation to load- and repetition duration-accentuated (ECC) training as well as the use of isokinetic and isoinertial training methods, there is a relative dearth of literature considering multi-joint, multi-exercise RT interventions. The present study considered 59 male and female participants randomly divided in to 3 sex counterbalanced groups; ECC only (ECC, n = 20), repetition duration-accentuated ECC (ECC-A, n = 20), and traditional (CON, n = 19) performing full-body, effort matched RT programmes for 2 days.week(-1) for 10 weeks. Outcomes were muscular performance, including absolute muscular endurance and predicted 1-repetition maximum, in addition to body composition. No significant between-groups differences were identified for change in muscular performance measures for leg press or chest press exercises, or for body composition changes. Analyses revealed a significantly greater improvement for CON compared with ECC groups (p < 0.05) for change in absolute muscular endurance for the pull-down exercise. Effect sizes for muscular performance changes were moderate to large for all groups and exercises (0.75-2.00). The present study supports previous research that ECC-only training produces similar improvements in muscular performance to traditional training where intensity of effort is controlled. Data herein further supports the use of uncomplicated, low-volume RT to momentary failure as an efficacious method of improving muscular performance in trained persons.