An Examination of Muscle Activation and Power Characteristics While Performing the Deadlift Exercise With Straight and Hexagonal Barbells

Abstract

The deadlift exercise is commonly performed to develop strength and power, and to train the lower-body and erector spinae muscle groups. However, little is known about the acute training effects of a hexagonal barbell vs. a straight barbell when performing deadlifts. Therefore, the purpose of this study was to examine the hexagonal barbell in comparison with the straight barbell by analyzing electromyography (EMG) from the vastus lateralis, biceps femoris, and erector spinae, as well as peak force, peak power, and peak velocity using a force plate. Twenty men with deadlifting experience volunteered to participate in the study. All participants completed a 1 repetition maximum (1RM) test with each barbell on 2 separate occasions. Three repetitions at 65 and 85% 1RM were performed with each barbell on a third visit. The results revealed that there was no significant difference for 1RM values between the straight and hexagonal barbells (mean ± SD in kg = 181.4 ± 27.3 vs. 181.1 ± 27.6, respectively) (p > 0.05). Significantly greater normalized EMG values were found from the vastus lateralis for both the concentric (1.199 ± 0.22) and eccentric (0.879 ± 0.31) phases of the hexagonal-barbell deadlift than those of the straight-barbell deadlift (0.968 ± 0.22 and 0.559 ± 1.26), whereas the straight-barbell deadlift led to significantly greater EMG values from the bicep femoris during the concentric phase (0.835 ± 0.19) and the erector spinae (0.753 ± 0.28) during the eccentric phase than the corresponding values for the hexagonal-barbell deadlift (0.723 ± 0.20 and 0.614 ± 0.21) (p ≤ 0.05). In addition, the hexagonal-barbell deadlift demonstrated significantly greater peak force (2,553.20 ± 371.52 N), peak power (1,871.15 ± 451.61 W), and peak velocity (0.805 ± 0.165) values than those of the straight-barbell deadlift (2,509.90 ± 364.95 N, 1,639.70 ± 361.94 W, and 0.725 ± 0.138 m·s, respectively) (p ≤ 0.05). These results suggest that the barbells led to different patterns of muscle activation and that the hexagonal barbell may be more effective at developing maximal force, power, and velocity.

The Effect of Set Up Position on EMG Amplitude, Lumbar Spine Kinetics, and Total Force Output During Maximal Isometric Conventional-Stance Deadlifts

“…These two deadlift variations have been shown to increase the knee moment and torque in comparison to a conventional deadlift. This results in increased activation of the quadriceps to counteract this moment [ 8 , 12 , 14 , 15 ] as well as a reduction in the biceps femoris activation [ 15 ]. This was also demonstrated in the present study for the FBDL, as the increased knee extensor moment corresponded with increased quadricep activation and reduced biceps femoris activation.…”

Comparison of Different Minimal Velocity Thresholds to Establish Deadlift One Repetition Maximum

“…Such extreme differences between actual deadlift 1RM velocity, both mean propulsion phase and mean acceleration phase, and the MVT equivalents may be partially explained by the considerable differences in the resistance exercises that have been studied to date (bench press and back squat) and the deadlift. As the name suggests, the deadlift begins without assistance from the stretch-shortening cycle [ 6 , 7 , 11 ]. This could explain why differences between velocities recorded during the last repetition of a set to volitional fatigue with 70% 1RM and 80% deadlift 1RM and the velocities recorded during actual deadlift 1RM were so large.…”

“…The deadlift is an exercise that is often included in athletic strength and conditioning programs [ 6 , 7 , 8 ]. However, nothing is known about the load-velocity profile of the deadlift and whether the deadlift MVT matches the barbell velocity of 1RM deadlift performance.…”

“…This represents a critical gap in the literature. The deadlift is considered one of, if not the most taxing resistance exercise [ 7 , 8 ]. Therefore, demonstrating that the load-velocity profiling approach could be accurately applied to the deadlift could provide strength and conditioning practitioners with a more energy- and training time-efficient method of assessing deadlift 1RM.…”

Electromyographic activity in the gluteus medius, gluteus maximus, biceps femoris, vastus lateralis, vastus medialis and rectus femoris during the Monopodal Squat, Forward Lunge and Lateral Step-Up exercises

“…Counterresistance training constitutes one of the basic pillars of maintaining an optimal physical condition [1], producing increased muscle mass and improvements in muscle strength [2], being of great importance for increasing athlete performance and in the prevention and recovery of possible injuries [3]. In this sense, the Squat and Deadlift exercises and their variants, such as the Parallel Back Squat [4], Partial Back & Full Back Squat [5], Hexagonal Barbell and Straight Deadlift exercises [6], are commonly used in muscle conditioning as basic practices for lower-body strength training [7,8].…”