Article

Sitting Back in the Squat

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Abstract

SQUATTING AND ITS VARIATIONS ARE PERHAPS THE MOST USED EXERCISE IN STRENGTH AND CONDITIONING. HOWEVER, THERE IS CONTROVERSY ON THE PROPER METHOD OF PERFORMING THE SQUATTING EXERCISE. WHEN COACHING THE SQUATTING EXERCISE, MECHANICS OF THE JOINTS AND SEGMENTS SHOULD BE CAREFULLY CONSIDERED TO OPTIMIZE THE TRAINING STIMULUS AND MINIMIZE INJURY POTENTIAL.

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... The rack that the barbell rests on should have a load-bearing capacity that well exceeds the desired training load, ultimately preventing any training mishaps resulting from suboptimal supportive structure (29). Flooring should be rigid, level, and provide the best possible base to apply force (7). Finally, weights used to load the bar should be calibrated accurately to prevent uneven loading on either side of the bar, and collar "clips" should be properly used to secure weights, further preventing uneven loading and subsequent injury risk. ...
... The lifter should keep the hips close to the bar's line of action during the LBBS by maintaining tension in the gluteus maximus. A normal lordotic curve should be maintained throughout the lift (7,28). It may be pragmatic for the lifter to visualize one imaginary line on the inferior aspect of the rib cage and another on the superior aspect of the pelvis, keeping both lines parallel to one another ( Figure 3). ...
... Once the lifter is braced, fully upright, and is ready to initiate the squat, they should focus on opening at the hips and dropping straight down, simulating a ballet "plie" (7). The hips, knees, and ankles flex simultaneously, facilitating an upright torso position from the start of descent (28,36). ...
Article
The low-bar back squat (LBBS) is a barbell squat variation that emphasizes hip musculature through use of forward lean. This characteristic, among others, allows greater loads to be lifted and can facilitate rehabilitation in a compromised knee joint. Correct technique should be instructed to promote proper execution. This article aims to discuss the anatomical and technical differences between the high-bar back squat and LBBS, define LBBS-specific technique, and provide practitioners strategies to select the best version for their lifters.
... Analysis of GRFs can aid in the calculation of joint moments of the knee and hip when paired with segment orientation (Faber, Kingma, & van Dieën, 2010). In the BBS, GRF location and load on the lower extremity is influenced largely by the position of the upper body, due its larger mass (Chiu, 2009). As the mass lifted is increased in a back-squat, the resultant GRF produced is increased significantly and ...
... This forward lean, is required to maintain the barbell over the COM, which effectively maximises the posterior displacement of the hips, and therefore increases the force placed on the hips, in comparison to the knee joints. The unique position of the LBBS results in 1) a decreased trunk lever arm when placing the bar lower on the back, 2) a greater emphasis on the stronger musculature of the hip rather than the musculature of the knee joint and, 3) an increase in stability and a potential decrease in stress placed on the lumbar region and ankle, when (Fv) due to its larger mass (Chiu, 2009). Moreover, as the load that is applied to the trapezius musculature via the barbell is increased, the resultant Fv produced is increased significantly and in proportion to the load increase in both the concentric and eccentric phases of the squat movement (Ebben & Jensen, 2002;Ebben et al., 2012;Flanagan & Salem, 2007;Kellis, Arambatzi, & Papadopoulos, 2005;Zink, Perry, Robertson, Roach, & Signorile, 2006). ...
... The centre of pressure is the point on the ground at which the vertical GRF vector originates (Benda, Riley, & Krebs, 1994). The upper body has a larger mass than the lower body (Chiu, 2009), and therefore humans are inherently unstable, and require effective control mechanisms to constantly resist perturbation (Winter, 1995). This inherent instability is expressed in three planes of motion when load is added to the upper body via a barbell, as in the case of the HBBS and/or LBBS (Schick et al., 2010). ...
Thesis
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The barbell back-squat is one of the most common exercises in strength and conditioning practice; especially in Olympic weightlifting and powerlifting. There are two main bar placements within the back-squat; the high-bar and low-bar positions. The high-bar position, favoured by Olympic weightlifters, closely resembles the upright body position of the two competition lifts of the sport; the snatch and clean and jerk. The low-bar position, favoured by powerlifters, typically allows greater loads to be lifted by utilising the posterior-chain musculature during the back-squat (one of the three competition lifts in the sport). Unfortunately, little research exists comparing the high-bar back-squat with the low-bar back-squat, and no research has examined either lift above 90% of one repetition maximum. Furthermore, no authors have biomechanically compared the high-bar back-squat to the Olympic lifts (e.g. snatch and clean and jerk). The aims of this thesis were to (1) review the current literature and quantitatively assess the kinetic and kinematic findings among the limited research; (2) compare and contrast the high-bar back-squat and low-bar back-squat up to maximal effort; and (3) assess the differences and/or similarities between the high-bar back-squat and the Olympic lifts. Through an extensive literature review, the high-bar back-squat was found to commonly present a larger hip angle, smaller knee angle and equivalent ankle angle compared to the low-bar back-squat; inferring the high-bar placement creates a more upright truck position for the lifter and requires more quadriceps muscle activation. Experimentally, these findings were confirmed with the high-bar back-squat producing larger hip angles and smaller knee angles compared to the powerlifters (16–21% larger and 10–12% smaller, respectively) and low-bar controls (16–21% larger and 10–12% smaller, respectively). While the Olympic weightlifters and powerlifters lifted similar relative loads, the low-bar controls were able to lift 2.5–5.2% larger relative loads compared to the high-bar controls. As expected, the high-bar back-squat also showed similar kinematics to the snatch and the clean but substantially different kinetics across all loads lifted. Performing a back-squat with a low-bar placement, situates the lifter (advanced and recreational) in a stronger position to lift larger loads compared to the high-bar placement. The establishment of a more advantageous kinematic posture during the low-bar back-squat could potentially maximise the utilisation of the stronger posterior hip musculature thus increasing the stability and moment arm at the hip. The low-bar back-squat therefore appears to provide the best chance of lifting the largest relative load. The kinematic similarities in posture between the high-bar back-squat and the Olympic lifts suggests the potential of similar trunk, hip and thigh muscular activity of key stabilising muscles and repetitive positional alignment in the “catch” position. The differing kinetics however, are more likely due to technical differences between the high-bar back-squat, snatch and clean; wherein the Olympic lifts require additional elements of upper-body strength and stability. The high-bar back-squat does appear to yield an efficient carryover to the Olympic lifts as a suitable supplementary exercise; provided the technical components of the lifts are maintained.
... Powerlifters typically back squat with a low-bar position with the barbell resting further down the spine (8). In this instance, the natural response to this altered bar position is a purposeful increase in hip flexion and torso lean (16); thus, accommodating the lowerbar position and change in center of mass. ...
... preferred choice. However, some literature has suggested that this variation may increase shear forces at the lumbar spine (8,14). Considering the low-bar squat is characterized by a naturally increasing forward lean (40), there may be a propensity to lose form under maximal loads, especially for those athletes unfamiliar with this variation or already exhibiting a forward lean during the squat pattern. ...
Article
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The high-bar back squat is often considered a cornerstone in an athlete's physical training program because of its capacity to enhance lower-body strength development. However, movement compensations are common with many exhibiting an "excessive forward lean" during their technique. This article aims to outline the potential reasons for this compensation. Furthermore, possible solutions that coaches could consider to address excessive forward lean and optimize high-bar back squat technique have been offered.
... In the back-squat, the resultant ground reaction force, and load on the lower extremity is influenced largely by the position of the upper body because of its larger mass (8). As the load of the back-squat is increased, the resulting F v also increases in a proportional fashion (27,43,91) during both the concentric and eccentric phases of the movement (20,21). ...
Article
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The back-squat is a common exercise in strength and conditioning, for a variety of sports. It is widely regarded as a fundamental movement to increase and measure lower-body and trunk function, as well as an effective injury rehabilitation exercise. There are typically two different bar positions used when performing the back-squat; the traditional 'high-bar' back-squat (HBBS) and the 'low-bar' back-squat (LBBS). Different movement strategies are employed to ensure that the center-of-mass remains in the base-of-support for balance during the execution of these lifts. These movement strategies manifest as differences in 1) joint angles, 2) vertical ground reaction forces and, 3) the activity of key muscles. This review showed that the HBBS is characterized by greater knee flexion, lesser hip flexion, a more upright torso and a deeper squat. The LBBS is characterized by greater hip flexion and therefore a greater forward lean. However, there are limited differences in vertical ground reaction forces between the HBBS and LBBS. The LBBS can also be characterized by greater muscle activity of the erector spinae, adductors and gluteal muscles, whereas the HBBS can be characterized by greater quadriceps muscle activity. Practitioners seeking to develop the posterior-chain hip musculature (i.e. gluteal, hamstring and erector muscle groups) may seek to utilize the LBBS. In comparison, those seeking to replicate movements with a more upright torso, and contribution from the quadriceps may rather seek to employ the HBBS in training.
... The descent of the FSq should be initiated by pushing one's hips behind them while flexing at the knees, which is often termed ''sitting back'' (6). As the hips descend, the knees should move anteriorly in the same plane as their feet. ...
Article
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THIS ARTICLE EXPLORES THE “FRONT SQUAT” (FSQ) AND ITS VARIATIONS AS PART OF THE “BIG THREE” (DEADLIFT, POWER CLEAN, AND SQUAT) EXERCISES PRESCRIBED BY STRENGTH AND CONDITIONING COACHES TO DEVELOP TOTAL BODY STRENGTH, TARGETING THE HIP EXTENSORS (GLUTEUS MAXIMUS), KNEE EXTENSORS (QUADRICEPS), KNEE FLEXORS (HAMSTRINGS), AND CORE MUSCULATURE (ERECTOR SPINAE, QUADRATUS LUMBORUM, OBLIQUES, RECTUS, AND TRANSVERSE ABDOMINIS). MORE SPECIFICALLY, THE PURPOSE OF THIS ARTICLE IS TO INTRODUCE STRENGTH AND CONDITIONING COACHES TO THE FSq TEACHING PROGRESSION, WITH SPECIFIC EMPHASIS ON DEVELOPING THE CORRECT BODY POSITIONING REQUIRED FOR EXECUTION OF THE FSQ.
... Given the technical difficulty in coaching and performing parallel squats, partial squats are also regularly taught and performed in communitybased gymnasiums. Limited knowledge of many trainers and trainees and poor instruction in the squat exercise is an issue (11). ...
Article
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It is commonplace for people involved in recreational weight training to limit squat depth to lift heavier loads. This study compares differences in movement kinetics when squatting in the full range of motion (FROM) vs. partial range of motion (PROM). Ten men with a 1-year minimum of resistance training attended 4 sessions each comprising 4 sets of squats following one of FROM for 10 repetitions (FROM10) at an intensity of 67% 1 repetition maximum (1RM) FROM squat, PROM for 10 repetitions (PROM10) at 67% 1RM PROM squat, FROM for 5 repetitions (FROM5) at 83% FROM squat or PROM for 5 repetitions (PROM5) at 83% 1RM PROM squat. Movement velocity was not specified. Squat kinetics data were collected using an optical encoder. Differences between conditions were analyzed by repeated-measures analysis of variance and expressed as mean differences and standardized (Cohen) effect sizes with 95% confidence limits. The PROM5 power was substantially more than the PROM10 (98 W, -21 to 217; mean, lower and upper 95% confidence limits), FROM5 (168 W, 47-289), and FROM10 (255 W, 145-365). The force produced during PROM5 was substantially more than PROM10 (372 N, 254-490), FROM5 (854 N, 731-977), and FROM10 (1,069 N, 911-1227). The peak velocity produced during FROM10 was substantially more than FROM5 (0.105 m·s(-1), 0.044-0.166), PROM10 (0.246 m·s(-1), 0.167-0.325), and PROM5 (0.305 m·s(-1), 0.228-0.382). The FROM5 was substantially more than FROM10 (86 J, 59-113), PROM5 (142 J, 90-194), and PROM10 (211 J, 165-257). Therefore, either range of motion can have practical implications in designing resistance training programs depending on if the training goal is related to power and force development, maximizing work output or speed. Moderate-load PROM training, common among recreational weight trainers, is unlikely to provide higher movement kinetics.
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Background: Plogging, an environment friendly trash workout is a combination of jogging with litter collection. People who are involved in the plogging carry a baggage for collecting the litter. Walking with a weight on one side causes the opposite side of the body to engage for stability and are also exposed to repetitive bending during the activity. Objectives: The purpose of this study is to evaluate the postural and physiological aspects of plogging activity. Methods: Thirty six subjects performed the litter collection in stoop, semi-squat, full squat and lunge postures respectively. Postures were analyzed using Rapid Entire Body Assessment (REBA). Physiological aspects of plogging, as well as a comparison of physical activity assessment during jogging and plogging, were investigated using a Polar M430 optical heart rate monitor. Statistical analysis were performed using SPSS version 23. Results: Mean±SD of full squat (5.13±0.59) and lunge (6.64±1.15) posture was found to have lesser risk score in comparison with the other two postures such as stoop (10.31±0.88) and semi-squat (8.11±1.40). Analysis from the Kruskal-Wallis and post hoc test showed that there is no significant interaction between the postures (p < 0.05). Paired Sample t-test showed that the energy expenditure for plogging and jogging are found to be similar (p > 0.05), but the fat percentages of calories burned is more in plogging (p < 0.05). Howerver plogging can be considered as a strenous activity as the % Cardiovascular strain of the activity had a mean value of (99.261% ). Conclusions: Ergonomic interventions are needed to play a vital role in minimizing the musculoskeletal related injuries and the physical strain of the task.
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Collins, KS, Klawitter, LA, Waldera, RW, Mahoney, SJ, and Christensen, BK. Differences in muscle activity and kinetics between the goblet squat and landmine squat in men and women. J Strength Cond Res XX(X): 000-000, 2021-Squat exercise variations are widely used and extensively researched. However, little information exists on the goblet squat (GBS) and landmine squat (LMS) and differences between men and women. This study investigated the differences in muscle activity and kinetics between the GBS and the LMS in 16 men and 16 women. Five repetitions of each squat type were performed loaded at 30% of their body mass. Vertical and anteroposterior ground reaction forces for the eccentric and concentric phases and peak vertical force were recorded with a force plate. Electromyographic (EMG) signals were recorded for the vastus medialis (VM), vastus lateralis (VL), semitendinosus (ST), and biceps femoris (BF). Normalized mean EMG values and ground reaction forces were analyzed with repeated measures analysis of variance (p < 0.05). Significant main effects for squat condition and sex were found. The LMS reduced activity in the quadriceps (VM and VL) muscles and vertical forces, while increasing posterior horizontal forces. In the LMS, men showed decreased ST activity, whereas women had decreased BF activity. Women exhibited greater quadriceps activity in both the GBS and LMS and greater ST in the LMS. Women also produced greater eccentric vertical force in both the GBS and LMS and less posterior horizontal forces in the LMS. The LMS may be useful to balance hamstring to quadriceps activity, increase horizontal loading, and reduce vertical loading. Conversely, the GBS can better target quadriceps activity and increase vertical loading. Sex differences should be considered for training programs that include the GBS and LMS.
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Barbell back squats are a popular exercise for developing lower extremity strength and power. However, this exercise has potential injury risks, particularly to the lumbar spine, pelvis and hip joint. Previous literature suggests heel wedges as a means of favourably adjusting trunk and pelvis kinematics with the intention of reducing such injury risks. Yet no direct biomechanical research exists to support these recommendations. Therefore, the purpose of this study was to examine the effects of heel wedges compared to barefoot on minimally loaded barbell back squats. Fourteen trained male participants performed a barbell back squat in bare feet or with their feet raised bilaterally with a 2.5cm wooden block while 3D kinematics, kinetics and electromyograms were collected. The heel wedge condition elicited significantly less forward trunk flexion angles at peak knee flexion, and peak external hip joint moments (p<0.05) compared to barefoot conditions. However, no significant differences were observed between conditions for trunk and pelvis angle differences at peak knee flexion (p>0.05). Lastly, no peak or root mean square differences in muscle activity were elicited between conditions (p>0.05). Our results lend support for the suggestions provided in literature aimed at utilizing heel wedges as a means of reducing excessive forward trunk flexion. However, the maintenance of a neutral spine, another important safety factor, is not affected by the use of heel wedges. Therefore, heel wedges may be a viable modification for reduction of excessive forward trunk flexion, but not for reduction in relative trunk-pelvis flexion during barbell back squats.
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Because a strong and stable knee is paramount to an athlete's or patient's success, an understanding of knee biomechanics while performing the squat is helpful to therapists, trainers, sports medicine physicians, researchers, coaches, and athletes who are interested in closed kinetic chain exercises, knee rehabilitation, and training for sport. The purpose of this review was to examine knee biomechanics during the dynamic squat exercise. Tibiofemoral shear and compressive forces, patellofemoral compressive force, knee muscle activity, and knee stability were reviewed and discussed relative to athletic performance, injury potential, and rehabilitation. Low to moderate posterior shear forces, restrained primarily by the posterior cruciate ligament (PCL), were generated throughout the squat for all knee flexion angles. Low anterior shear forces, restrained primarily by the anterior cruciate ligament (ACL), were generated between 0 and 60 degrees knee flexion. Patellofemoral compressive forces and tibiofemoral compressive and shear forces progressively increased as the knees flexed and decreased as the knees extended, reaching peak values near maximum knee flexion. Hence, training the squat in the functional range between 0 and 50 degrees knee flexion may be appropriate for many knee rehabilitation patients, because knee forces were minimum in the functional range. Quadriceps, hamstrings, and gastrocnemius activity generally increased as knee flexion increased, which supports athletes with healthy knees performing the parallel squat (thighs parallel to ground at maximum knee flexion) between 0 and 100 degrees knee flexion. Furthermore, it was demonstrated that the parallel squat was not injurious to the healthy knee. The squat was shown to be an effective exercise to employ during cruciate ligament or patellofemoral rehabilitation. For athletes with healthy knees, performing the parallel squat is recommended over the deep squat, because injury potential to the menisci and cruciate and collateral ligaments may increase with the deep squat. The squat does not compromise knee stability, and can enhance stability if performed correctly. Finally, the squat can be effective in developing hip, knee, and ankle musculature, because moderate to high quadriceps, hamstrings, and gastrocnemius activity were produced during the squat.
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Unlabelled: Some recommendations suggest keeping the shank as vertical as possible during the barbell squat, thus keeping the knees from moving past the toes. This study examined joint kinetics occurring when forward displacement of the knees is restricted vs. when such movement is not restricted. Seven weight-trained men (mean +/- SD; age = 27.9 +/- 5.2 years) were videotaped while performing 2 variations of parallel barbell squats (barbell load = body weight). Either the knees were permitted to move anteriorly past the toes (unrestricted) or a wooden barrier prevented the knees from moving anteriorly past the toes (restricted). Differences resulted between static knee and hip torques for both types of squat as well as when both squat variations were compared with each other (p < 0.05). For the unrestricted squat, knee torque (N.m; mean +/- SD) = 150.1 +/- 50.8 and hip torque = 28.2 +/- 65.0. For the restricted squat, knee torque = 117.3 +/- 34.2 and hip torque = 302.7 +/- 71.2. Restricted squats also produced more anterior lean of the trunk and shank and a greater internal angle at the knees and ankles. The squat technique used can affect the distribution of forces between the knees and hips and on the kinematic properties of the exercise. Practical applications: Although restricting forward movement of the knees may minimize stress on the knees, it is likely that forces are inappropriately transferred to the hips and low-back region. Thus, appropriate joint loading during this exercise may require the knees to move slightly past the toes.
Article
The purpose of this investigation was to determine if increases in external resistance during a squat movement would be controlled by proportionally scaling the net joint moment work or average net joint moment (NJM) at the hip, knee, and ankle. Eighteen experienced subjects performed 3 sets of 3 repetitions each of a squat movement using resistances of 25, 50, 75, and 100% of their 3-repetition maximum, while instrumented for biomechanical analyses. Standard inverse dynamics techniques and numerical integration were used to calculate the NJM work and average NJM of each joint. A combination of single-subject and group mean statistical analyses indicated that the neither the NJM work nor average NJM increased proportionately in response to increases in external loading. Results suggest a complex control strategy in which the hip was the dominant contributor, increased linearly with the external load, and had low variability. The knee and ankle contributions were neither as great nor as linear, and were highly variable, suggesting that they were influenced by more than just the external load. The disproportionate response of each joint to varying external resistances suggests that controlling the force output of multijoint chains requires further study and modifications to existing motor control theories.
Low Back Disorders: Evidence-Based Prevention and Rehabilitation
  • S Mcgill
McGill S. Low Back Disorders: Evidence-Based Prevention and Rehabilitation. Champaign, IL: Human Kinetics, 2002. pp. 118-124.