Effects of Stance Width and Barbell Placement on Kinematics, Kinetics, and Myoelectric Activity in Back Squats

Abstract

Barbell placement and stance width both affect lifting performance in the back squat around the sticking region. However, little is known about how these squat conditions separately could affect the lifting performance. Therefore, this study investigated the effects of stance width and barbell placement upon kinematics, kinetics, and myoelectric activity around the sticking region during a three-repetition maximum back squat. Nine men and nine women (body mass: 76.2 ±11.1, age: 24.9 ± 2.6) performed back squats with four different techniques, such as: high-bar narrow stance (HBNS), high-bar wide stance, low-bar narrow stance, and low-bar wide stance where they lifted 99.2 ± 23.6, 92.9 ± 23.6, 102.5 ± 24.7, and 97.1 ± 25.6 kg, respectively. The main findings were that squatting with a low-bar wide stance condition resulted in larger hip contributions to the total moment than the other squat conditions, whereas squatting with an HBNS resulted in greater knee contributions to the total moment together with higher vastus lateralis and less gluteus maximus myoelectric activity. Our findings suggest that training with an HBNS could be beneficial when targeting the knee extensors and plantar flexors, whereas a low-bar wide stance could be beneficial when targeting the hip extensors.

Are Diminishing Potentiation and Large Extensor Moments the Cause for the Occurrence of the Sticking Region in Maximum Free-Weight Barbell Back Squats among Resistance-Trained Males?

“…It seems that the body tries to be as effective as possible, since the squat movement starts with knee extension and plantar flexion movements ( van den Tillaar, 2015 ) rather than hip extension as these have lower moment arms ( Figure 5 ), together with peak sEMG amplitudes of the knee extensor and plantar flexor muscles ( Figure 7 ). This results in an increased torso forward lean during the first part of the lift as previously observed ( Larsen et al, 2021a , 2021b). However, with large knee flexion angles (pre-sticking and sticking regions) the vastii internal moment arm has been observed to decrease ( Kipp et al, 2022 ), while the net knee extension moment in back squats is stable during these regions ( Figure 6 ).…”

“…In addition, our kinetic data showed stable net hip extension moments until around 18–24 cm in the upward phase where the hip extension moment decreased almost linearly ( Figure 6 ). At the same time, the sEMG amplitude of all measured hip extensors and especially the gluteus maximus peaked after 24 cm ( Figure 7 ), i.e., at the start of the post-sticking region and where the barbell starts to accelerate again ( Larsen et al, 2021a ). These findings indicate that during the pre-sticking and sticking regions, the hip extension moments are at their highest as shown by the combination of stable maximal force output ( Figure 3 ) and the stable external hip moment arms ( Figure 5 ) during the isometric condition at these different heights.…”

“…The back squat is a popular resistance exercise to develop maximal strength in the lower extremities ( Schoenfeld, 2010 ). A successful back squat is typically performed by flexing the hip and knee joints to the hips lower than the knees before ascending back to the start position ( Larsen et al, 2021a ). At maximal and submaximal percentages of 1-repetition maximum (1-RM), a sticking region occurs during the upward phase ( Kompf and Arandjelović, 2017 ).…”

Relationship Between Stance Width Variation During One Repetition Maximum Barbell Hip Thrust Performance and Kicking Speed for Young Elite Silat Athletes

“…The significant differences (p<.001) only can be seen between males and females in the WSW stance. This finding is interesting as stance width is often considered an essential factor in the execution of kicks, as it can affect balance, stability, and power generation during the kicking motion (Larsen et al, 2021;Lorenzetti et al, 2018). However, the results of this study suggest that in the specific context of barbell hip thrusts and their relationship to kicking speed, stance width does not play a significant role.…”

“…This is to ensure that participants were adequately rested before performing the 1RM of BHT as the final load and repetition to be used as the performance score for this study. The procedures were followed based on guidelines set forth by the National Strength and Conditioning Association (NSCA) (Larsen et al, 2021).…”