An electromyographic and kinetic comparison of conventional and Romanian deadlifts

Abstract

Background/objective: Significant biomechanical differences were found among deadlift variations. However, little is known about the differences between the conventional and the Romanian deadlifts. Therefore, the purpose of this study was to determine which deadlift technique is a better training protocol between the conventional and the Romanian deadlifts as indicated by the greater demand in muscle activities and joint kinetics. Methods: 21 males performed each deadlift with 70% of the Romanian deadlift one repetition maximum (1RM) determined using a 1RM testing. Myoelectric activities of the rectus femoris, biceps femoris, and gluteus maximus and lower extremity net joint torque (NJT) were compared. The variables were extracted through an electromyography system (EMG) and a three-dimensional motion analysis. The EMG values were normalized to the peak EMG activation from a submaximal non-isometric voluntary contraction. A two-way repeated measures analysis of variance was conducted for statistical analysis. The level of significance was set at 0.05. Results: Significantly greater normalized EMG values were found from the rectus femoris and gluteus maximus (58.57 ± 13.73 and 51.52 ± 6.08 %peak) of the conventional deadlift than those of the Romanian deadlift (25.26 ± 14.21 and 46.88 ± 7.39 %peak). The conventional deadlift indicated significantly greater knee and ankle NJTs (0.21 ± 0.13 and −0.33 ± 0.08 Nm/kg cm) than those of the Romanian deadlift (−0.28 ± 0.1 and −0.29 ± 0.06 Nm/kg cm). Conclusion: The conventional deadlift would be a better technique for training the rectus femoris and gluteus maximus than the Romanian deadlift as indicated by the greater EMG and NJT values.