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.