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Johansson DG, Marchetti PH, Stecyk SD, Flanagan SP. A Biomechanical Comparison Between the Safety-Squat Bar and Traditional Barbell Back Squat. J Strength Cond Res 2024; 38:825-834. [PMID: 38595263 DOI: 10.1519/jsc.0000000000004719] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/11/2024]
Abstract
ABSTRACT Johansson, DG, Marchetti, PH, Stecyk, SD, and Flanagan, SP. A biomechanical comparison between the safety-squat bar and traditional barbell back squat. J Strength Cond Res 38(5): 825-834, 2024-The primary objectives for this investigation were to compare the kinematic and kinetic differences between performing a parallel back squat using a traditional barbell (TB) or a safety-squat bar (SSB). Fifteen healthy, recreationally trained male subjects (23 + 4 years of age) performed the back squat with a TB and an SSB at 85% of their respective 1 repetition maximum with each barbell while instrumented for biomechanical analysis. Standard inverse dynamics techniques were used to determine joint kinematic and kinetic measures. A 2 × 3 (exercise × joint) factorial analysis of variance with repeated measures was used to determine the kinetic and kinematic differences between the squats while using the different barbells. Fisher's least significant difference post hoc comparisons showed that the TB resulted in significantly greater maximum hip flexion angle (129.33 ± 11.8° vs. 122.11 ± 12.1°; p < 0.001; d = 1.80), peak hip net joint extensor torque (2.54 ± 0.4 Nm·kg -1 vs. 2.40 ± 0.4 Nm·kg -1 ; p = 0.001; d = 1.10), hip net extensor torque mechanical energy expenditure (MEE; 2.81 ± 0.5 Nm·kg -1 vs. 2.58 ± 0.6 Nm·kg -1 ; p = 0.002; d = 0.97), and ankle net joint plantar flexor torque MEE (0.32 ± 0.09 J·kg -1 vs. 0.28 ± 0.06 J·kg -1 ; p = 0.029; d = 0.63), while also lifting significantly (123.17 ± 20.8 kg vs. 117.17 ± 20.8 kg; p = 0.005; d = 0.858) more weight than the SSB. The SSB resulted in significantly higher maximum knee flexion angles (116.82 ± 5.8° vs. 115.65 ± 5.6°; p = 0.011; d = 0.75) than the TB, with no significant difference in kinetics at the knee. The TB may be preferred to the SSB for developing the hip extensors and lifting higher maximum loads. The SSB may be advantageous in situations where a more upright posture or a lower load is preferred while creating a similar demand for the knee joint.
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Affiliation(s)
- David G Johansson
- Department of Kinesiology, California State University, Northridge, Northridge, California
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Goodman W, Flores V, Cotter JA, Graham D, Becker J. Support moment distribution during the back squat at different depths and loads in recreationally trained females. J Sci Med Sport 2024; 27:119-124. [PMID: 38036316 DOI: 10.1016/j.jsams.2023.11.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Revised: 09/20/2023] [Accepted: 11/01/2023] [Indexed: 12/02/2023]
Abstract
OBJECTIVES The squat is used in athletic and clinical settings. However, the coordination of the lower extremity during the lift is not well understood. The purpose was to compare the peak moments of the lower extremity joints at three squat depths (above parallel, parallel and full) and three squat loads (unloaded, 50 % 1 repetition maximum, and 85 % of depth specific 1 repetition maximum) and find their contribution to support (Ms). DESIGN Nineteen females performed squats in a randomized order. METHODS Inverse dynamics and Winter's Ms equation were used to calculate peak moments of the hip, knee and ankle and calculate their contribution to Ms (α < 0.05). RESULTS Peak hip and ankle extensor moments varied with load but not depth and were greatest when using 85 % 1 repetition maximum. Peak knee extensor moments demonstrated a depth by load interaction. Within each depth as load increased so too did peak knee extensor moments and were highest squatting below parallel when loaded. The hip and knee contribution to Ms demonstrated a depth by load interaction while the ankle was only influenced by load. Within each depth as load increased hip contribution increased whereas the knee decreased contribution. When squatting with load the contribution of the hip decreased at below parallel while the knee increased. CONCLUSIONS To maximize peak hip moments squat with high load and to maximize peak knee moments squat deep with high load; however, depth and load dosages should be taken into consideration based on the status and goals of the individual.
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Affiliation(s)
- William Goodman
- Department of Food Systems, Nutrition, & Kinesiology, Montana State University, USA.
| | - Victoria Flores
- Department of Kinesiology and Nutrition, University of Illinois Chicago, USA
| | - Joshua A Cotter
- Department of Kinesiology, California State University, Long Beach, USA
| | - David Graham
- School of Health Sciences and Social Work, Griffith University Gold Coast, AU
| | - James Becker
- Department of Food Systems, Nutrition, & Kinesiology, Montana State University, USA
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Dagnese F, Martins EDA, da Silva FS, Mota CB, Copetti F. Joint knee loads during squat with constant or variable resistance in males. A clinical trial. J Bodyw Mov Ther 2024; 37:392-398. [PMID: 38432835 DOI: 10.1016/j.jbmt.2023.11.044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Revised: 10/30/2023] [Accepted: 11/24/2023] [Indexed: 03/05/2024]
Abstract
BACKGROUND In the squat movement, the use of constant resistance (CR) generates greater compression and shear forces close to 90° of knee flexion, increasing joint overload. However, when used variable resistance (VR) there is no consensus about the effect of knee joint load. The aim of this study was to compare knee torques using constant or variable resistance during the squat exercise. METHODS Twenty-one healthy male subjects (mean age, 24 [SD, 3] years; height, 1.76 [SD, 0.04] m), who practice squats during strength training routine. Were simultaneously record data from the platform force and tridimensional kinematic to obtain torques around knee. 15 repetitions were performed up to maximum knee flexion with the use of variable (RV) or constant (CR) resistance in a single session. RESULTS Significant differences regarding the angles only in the sagittal plane at the end of the ascending phase of the squat, with less knee extension in the VR condition. In the sagittal and frontal planes, lower values of extensor and abductor torque were found in the VR condition at the angles of greater knee flexion. CONCLUSION The use of variable resistance compared to constant resistance seems to be an alternative to be considered when the objective is to minimize the internal loads on the knee joint in exercises such as the squat in amplitudes of greater flexion. This study indicated that VR helps subjects who are learning the squat movement, enabling the application of this knowledge in physical therapy or physical training clinics.
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Affiliation(s)
- Frederico Dagnese
- Biomechanics Laboratory, Sports Centre, Federal University of Santa Catarina, Santa Catarina, Brazil; Biomechanics Laboratory, Physical Education and Sports Centre, Federal University of Santa Maria, Santa Maria, Brazil; Stúdio I - Pilates and Body Therapies, Santa Maria, Brazil.
| | - Elisandro de Assis Martins
- Biomechanics Laboratory, Physical Education and Sports Centre, Federal University of Santa Maria, Santa Maria, Brazil; Stúdio I - Pilates and Body Therapies, Santa Maria, Brazil.
| | - Fabrício Santana da Silva
- Biomechanics Laboratory, Physical Education and Sports Centre, Federal University of Santa Maria, Santa Maria, Brazil.
| | - Carlos Bolli Mota
- Biomechanics Laboratory, Physical Education and Sports Centre, Federal University of Santa Maria, Santa Maria, Brazil.
| | - Fernando Copetti
- Biomechanics Laboratory, Physical Education and Sports Centre, Federal University of Santa Maria, Santa Maria, Brazil.
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Goodman WW, Helms E, Graham DF. Individual Muscle Contributions to the Acceleration of the Center of Mass During the Barbell Back Squat in Trained Female Subjects. J Strength Cond Res 2023; 37:1947-1954. [PMID: 37556813 DOI: 10.1519/jsc.0000000000004506] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/11/2023]
Abstract
ABSTRACT Goodman, WW, Helms, E, and Graham, DF. Individual muscle contributions to the acceleration of the center of mass during the barbell back squat in trained female subjects. J Strength Cond Res 37(10): 1947-1954, 2023-The squat is used to enhance performance and rehabilitate the lower body. However, muscle forces and how muscles accelerate the center of mass (CoM) are not well understood. The purpose was to determine how lower extremity muscles contribute to the vertical acceleration of the CoM when squatting to parallel using 85% one-repetition maximum. Thirteen female subjects performed squats in a randomized fashion. Musculoskeletal modeling was used to obtain muscle forces and muscle-induced accelerations. The vasti, soleus, and gluteus maximus generated the largest upward accelerations of the CoM, whereas the muscles that produced the largest downward acceleration about the CoM were the hamstrings, iliopsoas, adductors, and tibialis anterior. Our findings indicate that a muscle's function is task and posture specific. That is, muscle function depends on both joint position and how an individual is interacting with the environment.
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Affiliation(s)
- William W Goodman
- Montana State University, College of Education, Health and Human Development, Bozeman, Montana; and
| | - Eric Helms
- Sport Performance Research Institute New Zealand (SPRINZ), Auckland University of Technology, Auckland, New Zealand
| | - David F Graham
- Montana State University, College of Education, Health and Human Development, Bozeman, Montana; and
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Illmeier G, Rechberger JS. The Limitations of Anterior Knee Displacement during Different Barbell Squat Techniques: A Comprehensive Review. J Clin Med 2023; 12:jcm12082955. [PMID: 37109294 PMCID: PMC10143703 DOI: 10.3390/jcm12082955] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2023] [Revised: 04/14/2023] [Accepted: 04/17/2023] [Indexed: 04/29/2023] Open
Abstract
Based on seminal research from the 1970s and 1980s, the myth that the knees should only move as far anterior during the barbell squat until they vertically align with the tips of the feet in the sagittal plane still exists today. However, the role of both the hip joint and the lumbar spine, which are exposed to high peak torques during this deliberate restriction in range of motion, has remained largely unnoticed in the traditional literature. More recent anthropometric and biomechanical studies have found disparate results regarding anterior knee displacement during barbell squatting. For a large number of athletes, it may be favorable or even necessary to allow a certain degree of anterior knee displacement in order to achieve optimal training outcomes and minimize the biomechanical stress imparted on the lumbar spine and hip. Overall, restricting this natural movement is likely not an effective strategy for healthy trained individuals. With the exception of knee rehabilitation patients, the contemporary literature suggests it should not be practiced on a general basis.
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Affiliation(s)
- Gabriel Illmeier
- Department of Strength & Conditioning, Nachwuchsleistungssportzentrum Steiermark, 8010 Graz, Austria
| | - Julian S Rechberger
- Mayo Clinic Graduate School of Biomedical Sciences, Mayo Clinic, Rochester, MN 55905, USA
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN 55905, USA
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Svensson F, Aasa U, Strong A. Textile electromyography electrodes reveal differences in lower limb muscle activation during loaded squats when comparing fixed and free barbell movement paths. Front Sports Act Living 2022; 4:1021323. [PMID: 36524056 PMCID: PMC9745169 DOI: 10.3389/fspor.2022.1021323] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2022] [Accepted: 11/09/2022] [Indexed: 08/13/2023] Open
Abstract
INTRODUCTION Traditional recordings of muscle activation often involve time-consuming application of surface electrodes affixed to the skin in laboratory environments. The development of textile electromyography (EMG) electrodes now allows fast and unobtrusive assessment of muscle activation in ecologically valid environments. In this study, textile EMG shorts were used to assess whether performing squats with the barbell resting freely on the shoulders or using a Smith machine for a fixed barbell movement path is preferable for maximizing lower limb muscle activation. METHODS Sixteen athletes performed free and fixed barbell squats in a gym with external loads equivalent to their body mass. Quadriceps, hamstrings and gluteus maximus activation was measured bilaterally with textile EMG electrodes embedded in shorts. RESULTS Mean quadriceps activation was greater for the free compared with the fixed movement path for the right (mean difference [MD] 14μV, p = 0.04, ηp 2 = 0.28) and left leg (MD 15μV, p = 0.01, ηp 2 = 0.39) over the entire squat and specifically during the first half of the eccentric phase for the left leg (MD 7μV, p = 0.04, d = 0.56), second half of the eccentric phase for both legs (right leg MD 21μV, p = 0.05, d = 0.54; left leg MD 23μV, p = 0.04, d = 0.52) and the first half of the concentric phase for both legs (right leg MD 24μV, p = 0.04, d = 0.56; left leg MD 15μV, p = 0.01, d = 0.72). Greater hamstrings activation for the free path was seen for the second half of the eccentric phase (left leg MD 4μV, p = 0.03, d = 0.58) and first half of the concentric phase (right leg MD 5μV, p = 0.02, d = 0.72). No significant differences were found for gluteus maximus. DISCUSSION Textile EMG electrodes embedded in shorts revealed that to maximize thigh muscle activity during loaded squats, a free barbell movement path is preferable to a fixed barbell movement path.
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Affiliation(s)
| | | | - Andrew Strong
- Department of Community Medicine and Rehabilitation, Physiotherapy, Umeå University, Umeå, Sweden
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Park JH, Lee SJ, Shin HJ, Cho HY. Influence of Loads and Loading Position on the Muscle Activity of the Trunk and Lower Extremity during Squat Exercise. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:ijerph192013480. [PMID: 36294056 PMCID: PMC9602963 DOI: 10.3390/ijerph192013480] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Revised: 10/13/2022] [Accepted: 10/15/2022] [Indexed: 05/13/2023]
Abstract
This study aimed to investigate the effect of the load and bar position on trunk and lower extremity muscle activity during squat exercise. High bar back squats (HBBS) and low bar back squats (LBBS) were performed in random order at 50%, 60%, and 70% loads of one repetition maximum by 28 experienced healthy adult men who had been performing squats for at least one year. Before the experiment, the maximal voluntary contraction of the vastus medialis, vastus lateralis, rectus femoris, biceps femoris, rectus abdominis, transverse abdominis, external oblique, and erector spinae muscles was measured by means of surface electromyography. In addition, eccentric and concentric exercises were performed for 3 s each to measure the muscle activity. There was a significant difference in muscle activity according to the load for all muscles in the eccentric and concentric phases (p < 0.05), indicating that muscle activity increased as the load increased. In addition, in the comparison between HBBS and LBBS, significant differences were shown in all lower extremity muscles and all trunk muscles except for the external oblique in the concentric phase according to the bar position (p < 0.05). HBBS showed a higher muscle activity of the lower extremity in the eccentric and concentric phases than in LBBS, while LBBS showed a higher muscle activity of the trunk muscle in the eccentric and concentric phases than in HBBS (p < 0.05). HBBS requires more force in the lower extremity than LBBS and is particularly advantageous in strengthening the muscular strength of the quadriceps. In contrast, LBBS requires more muscle activity in the trunk than HBBS and is more effective in carrying heavier loads because of the advantage of body stability. This study suggests that rehabilitation experts apply the bar position and load as important variables affecting the intensity and method of training for target muscle strengthening of the lower extremities and trunk.
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Affiliation(s)
- Ju-Hyung Park
- Department of Health Science, Gachon University Graduate School, Incheon 21936, Korea
| | - Seung-Jea Lee
- Department of Medical Sciences, Soonchunhyang University, Asan-si 31538, Korea
| | - Ho-Jin Shin
- Department of Health Science, Gachon University Graduate School, Incheon 21936, Korea
- Correspondence: (H.-J.S.); (H.-Y.C.); Tel.: +82-32-820-4420 (H.-J.S.); +82-32-820-4560 (H.-Y.C.)
| | - Hwi-Young Cho
- Department of Health Science, Gachon University Graduate School, Incheon 21936, Korea
- Department of Physical Therapy, Gachon University, Incheon 21936, Korea
- Correspondence: (H.-J.S.); (H.-Y.C.); Tel.: +82-32-820-4420 (H.-J.S.); +82-32-820-4560 (H.-Y.C.)
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Coratella G. Appropriate Reporting of Exercise Variables in Resistance Training Protocols: Much more than Load and Number of Repetitions. SPORTS MEDICINE - OPEN 2022; 8:99. [PMID: 35907047 PMCID: PMC9339067 DOI: 10.1186/s40798-022-00492-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Accepted: 07/21/2022] [Indexed: 12/03/2022]
Abstract
Manipulating resistance training variables is crucial to plan the induced stimuli correctly. When reporting the exercise variables in resistance training protocols, sports scientists and practitioners often refer to the load lifted and the total number of repetitions. The present conceptual review explores all within-exercise variables that may influence the strength and hypertrophic gains, and the changes in muscle architecture. Together with the (1) load and (2) the number of repetitions, (3) performing repetitions to failure or not to failure, (4) the displacement of the load or the range of movement (full or partial), (5) the portion of the partial movement to identify the muscle length at which the exercise is performed, (6) the total time under tension, the duration of each phase and the position of the two isometric phases, (7) whether the concentric, eccentric or concentric-eccentric phase is performed, (8) the use of internal or external focus and (9) the inter-set rest may all have repercussions on the adaptations induced by each resistance exercise. Manipulating one or more variable allows to increase, equalize or decrease the stimuli related to each exercise. Sports scientists and practitioners are invited to list all aforementioned variables for each exercise when reporting resistance training protocols.
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Affiliation(s)
- Giuseppe Coratella
- Department of Biomedical Sciences for Health, Università degli Studi di Milano, Via Giuseppe Colombo 71, 20133, Milan, Italy.
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Kennedy D, Casebolt JB, Farren GL, Fiaud V, Bartlett M, Strong L. Electromyographic differences of the gluteus maximus, gluteus medius, biceps femoris, and vastus lateralis between the barbell hip thrust and barbell glute bridge. Sports Biomech 2022:1-15. [PMID: 35586943 DOI: 10.1080/14763141.2022.2074875] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Accepted: 05/03/2022] [Indexed: 10/18/2022]
Abstract
Hip extensor muscles are critical to sport performance as events requiring sprinting and forceful landings are highly dependent on these muscles. Despite biomechanical differences between the barbell hip thrust (BHT) and the barbell glute bridge (BGB), both are biomechanically efficient ways to load this musculature for training purposes. Research investigating the differences in muscular activity between the BHT and BGB has yet been conducted. The aim of this study was to investigate, through surface electromyography, if one exercise is more optimal than the other in producing greater muscle activation for specific hip extensor muscles. Ten male participants completed a two-part study protocol. Results revealed the BHT elicited significantly greater muscle activity within the vastus lateralis for peak and mean outcomes; however, the BGB elicited significantly greater muscle activity in the upper and lower gluteus maximus for peak and mean outcomes and mean outcome in the gluteus medius. Current findings suggest, the BGB is, at minimum, a superior substitute for the BHT for eliciting a larger magnitude of activity in the gluteus maximus. Future studies between the two exercises are warranted to discern which produces greater hypertrophy and whether adaption of the BHT or BGB transfers more optimally to sport performance.
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Affiliation(s)
- D Kennedy
- Department of Sports and Exercise Sciences, West Texas A&M University, Canyon, TX, USA
| | | | - G L Farren
- Department of Sports and Exercise Sciences, West Texas A&M University, Canyon, TX, USA
| | - V Fiaud
- Department of Sports and Exercise Sciences, West Texas A&M University, Canyon, TX, USA
| | - M Bartlett
- Department of Sports and Exercise Sciences, West Texas A&M University, Canyon, TX, USA
| | - L Strong
- Department of Sports and Exercise Sciences, West Texas A&M University, Canyon, TX, USA
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Lincoln MA, Wheeler SG, Knous JL. Safety Squat Bar Squat Technique and Biomechanics-Driven Programming. Strength Cond J 2022. [DOI: 10.1519/ssc.0000000000000717] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Pelvic Floor Muscle Strength in the First Trimester of Primipara: A Cross-Sectional Study. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:ijerph19063568. [PMID: 35329251 PMCID: PMC8954683 DOI: 10.3390/ijerph19063568] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/22/2022] [Revised: 03/09/2022] [Accepted: 03/14/2022] [Indexed: 01/20/2023]
Abstract
Background: Pelvic floor muscle (PFM) weakness is associated with stress urinary incontinence. Pregnancy is an important risk factor for PFM weakness. Studies evaluating PFM strength in the first trimester of pregnancy are still lacking. Our study aimed to describe pelvic floor function of the primipara in the first trimester of gestation and investigate the risk factors for PFM weakness. Methods: Primiparas aged 20~40 years with a singleton pregnancy less than 14 weeks of gestation were recruited, and data were collected via questionnaires on items that were suggested as associated with PFM weakness, followed by Modified Oxford Scale (MOS) on genital hiatus and perineal body and pelvic floor ultrasound evaluation for the thickness of the left and right levator ani muscles (LAM), right−left diameter of the levator hiatus (LH), and LH area. Participants were divided into three groups by MOS >3, =3, and <3 for data analysis. Results: A total of 380 participants completed the questionnaires and examinational analysis, of whom, 228, 98, and 54 were divided into Group 1, Group 2, and Group 3, respectively. The three groups were significantly different in the number of gestations and abortions, toilet types, and the right−left diameter of the LH (p < 0.05). Logistic regressive analysis showed that squatting toilet dominant (OR = 3.025; 95% CI: 1.623~5.638; p < 0.001) and a larger right−left diameter of the LH (OR = 1.065; 95% CI: 1.026~1.105; p = 0.001) were significantly associated with PFM weakness. Conclusions: Squatting toilet dominancy and longer right−left diameter of the LH are significantly associated with PFM weakness in primiparas in the first trimester. Sitting toilets should be recommended to women, especially pregnant women. Trial registration: The trial has been registered at Chinese Clinical Trial Registry (registration number: ChiCTR2000029618).
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Lower extremities joint angles during squats - underexplored parameter of standard rehabilitation and sports exercise. CENTRAL EUROPEAN JOURNAL OF SPORT SCIENCES AND MEDICINE 2022. [DOI: 10.18276/cej.2022.4-02] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/08/2023] Open
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Aniceto RR, Pirauá ALT, da Silva Leandro L, da Silva HCF, Silva DM, de Araújo LC, Costa PB, dos Santos HH. Lunges activate the gluteus maximus muscles more than back squats when both exercises are standardized. ISOKINET EXERC SCI 2021. [DOI: 10.3233/ies-210125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND: Squats are considered one of the main exercises for the lower limbs and are used in resistance training under different contexts, including rehabilitation and sports performance. OBJECTIVE: To compare the EMG activity of different muscles in back squat and lunge exercises in trained women. METHODS: Ten healthy women experienced in resistance training performed back squat and lunge exercises on a Smith machine (total work: 70% of 1RM, 1 set, 10 repetitions and 2-s/2-s of execution speed) with an interval of 20-min between exercises. Both exercises were standardized in relation to the trunk inclination and were performed with an erect trunk parallel to the cursor of the guided bar. RESULTS: The EMG activity of the vastus medialis (VM), vastus lateralis (VL), biceps femoris (BF), and gluteus maximus (GM) were analyzed. There were no significant differences in the EMG activity of the VM, VL, and BF muscles between the back squat and lunge exercises (P> 0.05); however, GM activation was greater during the lunge exercise (effect size = 1.15; P= 0.001). CONCLUSIONS: Lunges were more effective in recruiting the GM when compared to back squats. However, both exercises can be recommended when the goal is knee extensor and flexor muscle activity.
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Affiliation(s)
- Rodrigo Ramalho Aniceto
- Study and Research Group in Biomechanics and Psychophysiology of Exercise, Department of Physical Education and Sport, Federal Institute of Education, Science and Technology of Rio Grande do Norte, Currais Novos, RN, Brazil
- Laboratory of Kinesiology and Biomechanics, Department of Physical Education, Integrated Colleges of Patos, Patos, PB, Brazil
| | - André Luiz Torres Pirauá
- Study and Research Group in Biomechanics and Psychophysiology of Exercise, Department of Physical Education and Sport, Federal Institute of Education, Science and Technology of Rio Grande do Norte, Currais Novos, RN, Brazil
- Department of Physical Education, Rural Federal University of Pernambuco, Recife, PE, Brazil
| | - Leonardo da Silva Leandro
- Study and Research Group in Biomechanics and Psychophysiology of Exercise, Department of Physical Education and Sport, Federal Institute of Education, Science and Technology of Rio Grande do Norte, Currais Novos, RN, Brazil
- Associate Graduate Program in Physical Education UPE/UFPB, Department of Physical Education, Federal University of Paraiba, João Pessoa, PB, Brazil
- Laboratory of Kinesiology and Biomechanics, Department of Physical Education, Integrated Colleges of Patos, Patos, PB, Brazil
| | | | - Diego Mesquita Silva
- Study and Research Group in Biomechanics and Psychophysiology of Exercise, Department of Physical Education and Sport, Federal Institute of Education, Science and Technology of Rio Grande do Norte, Currais Novos, RN, Brazil
- Laboratory of Kinesiology and Biomechanics, Department of Physical Education, Integrated Colleges of Patos, Patos, PB, Brazil
| | - Leandro Cândido de Araújo
- Study and Research Group in Biomechanics and Psychophysiology of Exercise, Department of Physical Education and Sport, Federal Institute of Education, Science and Technology of Rio Grande do Norte, Currais Novos, RN, Brazil
- Laboratory of Kinesiology and Biomechanics, Department of Physical Education, Integrated Colleges of Patos, Patos, PB, Brazil
| | - Pablo Brando Costa
- Exercise Physiology Laboratory, Department of Kinesiology, California State University, Fullerton, USA
| | - Heleodório Honorato dos Santos
- Study and Research Group in Biomechanics and Psychophysiology of Exercise, Department of Physical Education and Sport, Federal Institute of Education, Science and Technology of Rio Grande do Norte, Currais Novos, RN, Brazil
- Associate Graduate Program in Physical Education UPE/UFPB, Department of Physical Education, Federal University of Paraiba, João Pessoa, PB, Brazil
- Physiotherapy Department, Federal University of Paraiba, João Pessoa, PB, Brazil
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Larsen S, Kristiansen E, Helms E, van den Tillaar R. Effects of Stance Width and Barbell Placement on Kinematics, Kinetics, and Myoelectric Activity in Back Squats. Front Sports Act Living 2021; 3:719013. [PMID: 34541522 PMCID: PMC8440835 DOI: 10.3389/fspor.2021.719013] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Accepted: 08/02/2021] [Indexed: 11/25/2022] Open
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.
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Affiliation(s)
- Stian Larsen
- Department of Sports Sciences and Physical Education, Nord University, Levanger, Norway
| | - Eirik Kristiansen
- Department of Sports Sciences and Physical Education, Nord University, Levanger, Norway
| | - Eric Helms
- Sports Performance Research Institute New Zealand, Auckland University of Technology, Auckland, New Zealand
| | - Roland van den Tillaar
- Department of Sports Sciences and Physical Education, Nord University, Levanger, Norway.,Sports Performance Research Institute New Zealand, Auckland University of Technology, Auckland, New Zealand
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Kalmus OE, Viru M, Alvar B, Naclerio F. Impact of Low Volume Velocity-Controlled vs. Repetition to Failure Resistance Training Session on Measures of Explosive Performance in a Team of Adolescents Basketball Players. Sports (Basel) 2021; 9:sports9080115. [PMID: 34437376 PMCID: PMC8402485 DOI: 10.3390/sports9080115] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Revised: 08/02/2021] [Accepted: 08/20/2021] [Indexed: 11/16/2022] Open
Abstract
This study examined the short-term effects (post 6 h and 24 h) of two equated (70% of 1 repetition maximum (1-RM)) low volume resistance exercise protocols: (i) velocity-controlled (VC) and (ii) repetition to failure (RTF) on upper and lower body performance in competitive adolescent male basketball players. Following a randomized, counterbalanced design, ten participants (age: 16 ± 0.5 years) completed either VC or RTF separated by 72 h. VC consisted of 4 sets of 5 explosive repetitions (≥90% of the maximum velocity). RTF involved 2 sets of 10-RM (with no velocity control). Measurements of 20-m sprint, countermovement jump (CMJ) and medicine ball toss (MBT) were collected before (baseline), post 6 h and 24 h after either VC or RTF. Increases of CMJ post 6 h (VC, +6.7%; RTF, +2.4%) and MBT post 24 h (VC, +4.6%; RTF, +4.2%) were observed after both VC and RTF. Only VC potentiated CMJ after 24 h (+2.0 ± 2.3%). No other changes or differences between protocols were observed. Performing a low volume exercise protocol, either VC or RTF, induced similar potentiation effects on the vertical jump (post 6 h) and medicine ball toss (post 24 h) in adolescent basketball players. Only the VC protocol was still effective to potentiate CMJ performance after 24 h.
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Affiliation(s)
- Ott-Erik Kalmus
- Centre for Exercise Activity and Rehabilitation, Institute for Lifecourse Development, School of Human Sciences, University of Greenwich, London SE10 9LS, UK;
- Correspondence: ; Tel.: +372-56-678-426
| | - Mehis Viru
- Institute of Sports Sciences and Physiotherapy, Faculty of Medicine, University of Tartu, 51008 Tartu, Estonia;
| | - Brent Alvar
- Department of Kinesiology, Point Loma Nazarene University, San Diego, CA 92106, USA;
| | - Fernando Naclerio
- Centre for Exercise Activity and Rehabilitation, Institute for Lifecourse Development, School of Human Sciences, University of Greenwich, London SE10 9LS, UK;
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A Biomechanical Comparison of the Safety-Bar, High-Bar and Low-Bar Squat around the Sticking Region among Recreationally Resistance-Trained Men and Women. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph18168351. [PMID: 34444101 PMCID: PMC8392107 DOI: 10.3390/ijerph18168351] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Revised: 07/28/2021] [Accepted: 08/02/2021] [Indexed: 11/24/2022]
Abstract
Barbell placement can affect squat performance around the sticking region. This study compared kinematics, kinetics, and myoelectric activity of the safety-bar squat with the high-bar, and low-bar squat around the sticking region. Six recreationally resistance-trained men (26.3 ± 3.1 years, body mass: 81 ± 7.7 kg) and eight women (22.1 ± 2.2 years, body mass: 65.7 ± 10.5 kg) performed three repetition maximums in all three squat conditions. The participants lifted the least load with the safety bar followed by the high-bar and then the low-bar squat. Greater myoelectric activity of the gluteus maximus was observed during safety-bar squats than high-bar squats. Also, larger knee extension moments were observed for the safety bar compared with low-bar squat. Men had higher myoelectric activity in the safety-bar condition for the gluteus maximus during all regions in comparison with women, and greater knee valgus at the second occurrence of peak barbell velocity. Our findings suggest that the more upright torso inclination during the safety-bar could allow greater gluteus maximus contribution to the hip extensor moment. Moreover, low-bar squats allowed the greatest loads to be lifted, followed by the high-bar and safety-bar squats, possibly due to the larger hip moments and similar knee moments compared to the other squat conditions. Therefore, when the goal is to lift the greatest load possible among recreationally trained men and women, they should first attempt squatting with a low-bar technique, and if the goal is to increase myoelectric activity in the gluteus maximus, a safety-bar squat may be the more effective than the high- bar squat.
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Arsenis S, Gioftsidou A, Smilios I, Malliou P, Chatzinikolaou A, Ispyrlidis I, Beneka A. Flywheel or free weight training for improvement of lower limbs strength? J Back Musculoskelet Rehabil 2021; 34:477-483. [PMID: 33492277 DOI: 10.3233/bmr-200151] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
BACKROUND New training methods are constantly used to improve the ability of skeletal muscles to develop strength. OBJECTIVE The aim of the present study was to investigate the effect of half-squat training with free weights and flywheel device on isokinetic knee muscle strength for well-trained amateur soccer players. METHODS Forty eight players were randomly divided into three groups (n= 16 each): Desmotech Training group (DT), Free Weight Training group (WT) and one Control Group (CON). DT and WT performed an eight-week half-squat training program, with two sessions per week. The DT group performed training with a flywheel device. Isokinetic concentric-eccentric strength assessments of the knee extensors-flexors muscle groups were performed at different angular velocities (60, 180 and 240∘/s). RESULTS The eight-week training program improved all the isokinetic joint moment indicators examined in the DT and WT groups (p< 0.01). The DT group achieved higher performances at all the isokinetic parameters examined, however, without statistically significant differences to the WT group. CONCLUSIONS Flywheel-based exercise is an effective training method and is suggested to be used to strengthen the lower limbs of soccer players.
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Larsen S, Kristiansen E, van den Tillaar R. New Insights About the Sticking Region in Back Squats: An Analysis of Kinematics, Kinetics, and Myoelectric Activity. Front Sports Act Living 2021; 3:691459. [PMID: 34169277 PMCID: PMC8217455 DOI: 10.3389/fspor.2021.691459] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Accepted: 05/06/2021] [Indexed: 01/25/2023] Open
Abstract
The aim of this study was to investigate barbell, joint kinematics, joint kinetics of hip, knee, and ankle in tandem with myoelectric activity around the sticking region in three-repetition maximum (3-RM) back squats among recreationally trained lifters. Unlike previous literature, this study also investigated the event of first-peak deacceleration, which was expected to be the event with the lowest force output. Twenty-five recreationally trained lifters (body mass: 70.8 ± 10.5, age: 24.6 ± 3.4, height: 172 ± 8.5) were tested in 3-RM back squats. A repeated one-way analysis of variance showed that ground reaction force output decreased at first peak deacceleration compared with the other events. Moreover, torso forward lean, hip moment arm, and hip contribution to total moment increased, whereas the knee moment arms and moment contribution to total moment decreased in the sticking region. Also, stable moment arms and moment contributions to total moment were observed for the ankle in the sticking region. Furthermore, the knee extensors together with the soleus muscle decreased myoelectric activity in the post-sticking region, while the gluteus maximus and biceps femoris increased myoelectric activity in the post-sticking region. Our findings suggest that the large hip moment arms and hip contributions to total moment together with a lower myoelectric activity for the hip extensors contribute to a poor biomechanical region for force output and, thereby, to the sticking region among recreationally trained lifters in 3-RM back squats.
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Affiliation(s)
- Stian Larsen
- Department of Sports Sciences and Physical Education, Nord University, Levanger, Norway
| | - Eirik Kristiansen
- Department of Sports Sciences and Physical Education, Nord University, Levanger, Norway
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Androulakis-Korakakis P, Gentil P, Fisher JP, Steele J. Comparison of Isolated Lumbar Extension Strength in Competitive and Noncompetitive Powerlifters, and Recreationally Trained Men. J Strength Cond Res 2021; 35:652-658. [PMID: 29979273 DOI: 10.1519/jsc.0000000000002722] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
ABSTRACT Androulakis-Korakakis, P, Gentil, P, Fisher, JP, and Steele, J. Comparison of isolated lumbar extension strength in competitive and noncompetitive powerlifters, and recreationally trained men. J Strength Cond Res 35(3): 652-658, 2021-Low-back strength has been shown to significantly impact performance in a plethora of sports. Aside from its effect on sport performance, low-back strength is strongly associated with low-back pain. A sport that heavily involves the lower-back musculature is powerlifting. This study looked to compare isolated lumbar extension (ILEX) strength in competitive and noncompetitive powerlifters, and recreationally trained men. Thirteen competitive powerlifters (CPL group; 31.9 ± 7.6 years; 173.4 ± 5.5 cm; 91.75 ± 18.7 kg), 10 noncompetitive powerlifters (NCPL group; 24 ± 3.5 years; 179 ± 4.8 cm; 92.39 ± 15.73 kg), and 36 recreationally trained men (RECT group; 24.9 ± 6.5 years; 178.5 ± 5.2 cm; 81.6 ± 10.0 kg) were tested for ILEX. Isolated lumbar extension strength was measured at every 12° throughout subject's full range of motion (ROM) and expressed as the following: "strength index (SI)" calculated as the area under a torque curve from multiple angle testing, average torque produced across each joint angle (AVG), and maximum torque produced at a single angle (MAX). Deadlift and squat strength were measured using 1 repetition maximum for the competitive and noncompetitive powerlifters. The following powerlifting characteristics were recorded for the competitive and noncompetitive powerlifters: primary deadlift stance, primary squat bar position, use of belt, use of performance-enhancing drugs, and use of exercises to target the lower-back musculature. Significant between-group effects were found for subject characteristics (age, stature, body mass, and ROM). However, analysis of covariance with subject characteristics as covariates found no significant between-group effects for SI (p = 0.824), AVG (p = 0.757), or MAX (p = 0.572). In conclusion, this study suggests that powerlifting training likely has little impact on conditioning of the lumbar extensors.
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Affiliation(s)
| | - Paulo Gentil
- Faculty of Physical Education, Federal University of Goiás, Goiânia, Brazil
| | - James P Fisher
- School of Sport, Health, and Social Science, Southampton Solent University, Southampton, United Kingdom; and
| | - James Steele
- School of Sport, Health, and Social Science, Southampton Solent University, Southampton, United Kingdom; and
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Chapman M, Larumbe-Zabala E, Triplett NT, Naclerio F. Velocity Change Estimation by Subjective Measures Over a Wide-Load Spectrum in Squat and Bench Press. J Strength Cond Res 2021; 35:S51-S56. [PMID: 33666592 DOI: 10.1519/jsc.0000000000003969] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
ABSTRACT Chapman, M, Larumbe-Zabala, E, Triplett, NT, and Naclerio, F. Velocity change estimation by subjective measures over a wide-load spectrum in squat and bench press. J Strength Cond Res 35(2S): S51-S56, 2021-This study compared whether the perception of effort measured on a repetition-by-repetition basis during continuous sets to failure is different between squat (SQ) and bench press (BP). After determining the one repetition maximum (1RM) value in both SQ and BP, 18 subjects (28.2 ± 5 years, 50% women) performed 7 sets to failure per exercise, separated by 24-48 hours, alternating SQ and BP, using the following relative load ranges: 30 < 40%, 40 < 50%, 50 < 60%, 60% < 70%, 70 < 80%, 80 < 90%, and >90%. The mean accelerative velocity (MAV) and rating of perceived exertion (RPE) using the OMNI-RES (0-10) scale were measured for every repetition of each set. The ability of the OMNI-RES (0-10) scale to identify velocity changes during continuous sets to volitional failure and to distinguish loading zones divided into 10% slots, from 30 to 100% of 1RM was confirmed for both SQ and BP. The RPE values measured at (a) the first repetition; (b) the repetition where MAV peaks; (c) the repetition where MAV drops by ≤10% compared the maximum and (d) the last repetition, showed no differences (p > 0.05, d < 0.2) between exercises. In conclusion, the same RPE scores can be applied to both exercises, for either estimating the relative load or monitoring changes in MAV during continuous sets to failure.
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Affiliation(s)
- Mark Chapman
- Institute for Lifecourse Development, School of Human Sciences, Center for Exercise Activity and Rehabilitation, University of Greenwich, London, United Kingdom
| | - Eneko Larumbe-Zabala
- School of Doctorate and Research, European University of Madrid, Madrid, Spain; and
| | - N Travis Triplett
- Department of Health and Exercise Science, Appalachian State University, Boone, North Carolina
| | - Fernando Naclerio
- Institute for Lifecourse Development, School of Human Sciences, Center for Exercise Activity and Rehabilitation, University of Greenwich, London, United Kingdom
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21
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Coratella G, Tornatore G, Caccavale F, Longo S, Esposito F, Cè E. The Activation of Gluteal, Thigh, and Lower Back Muscles in Different Squat Variations Performed by Competitive Bodybuilders: Implications for Resistance Training. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph18020772. [PMID: 33477561 PMCID: PMC7831128 DOI: 10.3390/ijerph18020772] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Revised: 01/12/2021] [Accepted: 01/14/2021] [Indexed: 01/12/2023]
Abstract
The present study investigated the activation of gluteal, thigh, and lower back muscles in different squat variations. Ten male competitive bodybuilders perform back-squat at full (full-BS) or parallel (parallel-BS) depth, using large feet-stance (sumo-BS), and enhancing the feet external rotation (external-rotated-sumo-BS) and front-squat (FS) at 80% 1-RM. The normalized surface electromyographic root-mean-square (sEMG RMS) amplitude of gluteus maximus, gluteus medius, rectus femoris, vastus lateralis, vastus medialis, adductor longus, longissimus, and iliocostalis was recorded during both the ascending and descending phase of each exercise. During the descending phase, greater sEMG RMS amplitude of gluteus maximus and gluteus medius was found in FS vs. all other exercises (p < 0.05). Additionally, FS elicited iliocostalis more than all other exercises. During the ascending phase, both sumo-BS and external-rotated-sumo-BS showed greater vastus lateralis and adductor longus activation compared to all other exercises (p < 0.05). Moreover, rectus femoris activation was greater in FS compared to full-BS (p < 0.05). No between-exercise difference was found in vastus medialis and longissimus showed no between-exercise difference. FS needs more backward stabilization during the descending phase. Larger feet-stance increases thigh muscles activity, possibly because of their longer length. These findings show how bodybuilders uniquely recruit muscles when performing different squat variations.
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Affiliation(s)
- Giuseppe Coratella
- Department of Biomedical Sciences for Health, Università degli Studi di Milano, via Giuseppe Colombo 71, 20133 Milano, Italy; (G.T.); (F.C.); (S.L.); (F.E.); (E.C.)
- Correspondence:
| | - Gianpaolo Tornatore
- Department of Biomedical Sciences for Health, Università degli Studi di Milano, via Giuseppe Colombo 71, 20133 Milano, Italy; (G.T.); (F.C.); (S.L.); (F.E.); (E.C.)
| | - Francesca Caccavale
- Department of Biomedical Sciences for Health, Università degli Studi di Milano, via Giuseppe Colombo 71, 20133 Milano, Italy; (G.T.); (F.C.); (S.L.); (F.E.); (E.C.)
| | - Stefano Longo
- Department of Biomedical Sciences for Health, Università degli Studi di Milano, via Giuseppe Colombo 71, 20133 Milano, Italy; (G.T.); (F.C.); (S.L.); (F.E.); (E.C.)
| | - Fabio Esposito
- Department of Biomedical Sciences for Health, Università degli Studi di Milano, via Giuseppe Colombo 71, 20133 Milano, Italy; (G.T.); (F.C.); (S.L.); (F.E.); (E.C.)
- IRCCS Galeazzi Orthopaedic Institute, 20122 Milano, Italy
| | - Emiliano Cè
- Department of Biomedical Sciences for Health, Università degli Studi di Milano, via Giuseppe Colombo 71, 20133 Milano, Italy; (G.T.); (F.C.); (S.L.); (F.E.); (E.C.)
- IRCCS Galeazzi Orthopaedic Institute, 20122 Milano, Italy
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22
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Comparison of Muscle Activation and Kinematics in 6-RM Squatting with Low and High Barbell Placement. J Hum Kinet 2020; 74:131-142. [PMID: 33312282 PMCID: PMC7706642 DOI: 10.2478/hukin-2020-0021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The aim of this study was to compare 6-RM muscle activation and kinematics in back squats with low and high barbell placements. Twelve resistance-trained males (23.5 ± 2.6 years, 86.8 ± 21.3 kg, 1.81 ± 0.08 m) with a minimum of 2 years of squatting experience performed a 6-RM using high and low barbell placements while muscle activation of eight muscles and joint kinematics were measured. During high barbell placement squats, lifting time was longer, with lower average velocity than low barbell placement. This was accompanied by a lesser knee flexion angle at the lowest point of the squat, and larger hip flexion angles during high, compared to low barbell squats. Furthermore, peak angular ankle, knee and hip velocities in the descending phase developed differently between conditions. No significant differences in muscle activation were found between conditions. Thus, our data suggests gross muscular adaptations between barbell placements may be similar over time, and therefore, from a muscular development standpoint, both squat styles are valid. Furthermore, unlike the low barbell placement, fatigue may manifest earlier itself in the high barbell squats during 6-RMs as sets progress toward a lifter’s maximal capacity, altering kinematics, especially in the last repetition.
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van den Tillaar R, Knutli TR, Larsen S. The Effects of Barbell Placement on Kinematics and Muscle Activation Around the Sticking Region in Squats. Front Sports Act Living 2020; 2:604177. [PMID: 33345183 PMCID: PMC7739732 DOI: 10.3389/fspor.2020.604177] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Accepted: 10/14/2020] [Indexed: 11/15/2022] Open
Abstract
The current study investigated the effects of barbell placement on kinematics and muscle activity during the sticking region of back squats. Ten healthy medium- to well-trained male powerlifters [age 26.1 ± 11.2 years, body mass 90.2 ± 18.3 kg, height 1.83 ± 0.09 m, five repetition maximum (5RM) 158 ± 29 kg] with at least 3 years of resistance-training experience were recruited. In a single session, participants performed 5RM movements using high bar and low bar squats, where absolute load, descent depth, and stance width were matched between squat conditions. The final repetition was analyzed using 3D kinematics and electromyography (EMG) around the sticking region. No differences in barbell and joint kinematics were observed in any phase, between both barbell modalities. Increased muscle activity in the rectus femoris, vastus medialis, and lower part of the erector spinae with the high bar, when compared with low bar conditions, was recorded. Furthermore, the gluteus maximus and medius had increased muscle activity over the three regions (pre-sticking > sticking > post-sticking), while the erector spinae, soleus, vastus lateralis, and rectus femoris experienced decreased muscle activity during the ascending phase. When depth and stance width were matched, the low bar technique was associated with lower erector spinae and quadriceps activity than the high bar technique. Thus, when the goal is to maximally activate knee extensors and the external load is matched, high bar placement would appear preferable.
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Affiliation(s)
| | - Tom Roar Knutli
- Department of Sports Sciences and Physical Education, Nord University, Bodø, Norway
| | - Stian Larsen
- Department of Sports Sciences and Physical Education, Nord University, Bodø, Norway
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Abstract
The aim of this study was to compare the effects of two resistance training programs including either a deadlift or a parallel squat on lower body maximal strength and power in resistance trained males. Twenty-five resistance trained men were randomly assigned to a deadlift group (DE; n = 14; age = 24.3 ± 4.1 y; body mass = 84.8 ± 14.2 kg; body height = 180.3 ± 6.8 cm) or to a squat group (SQ; n = 11; age = 22.3 ± 1.6 y; body mass = 83.0 ± 13.6 kg; body height 179.9 ± 6.1 cm). Both groups trained 3 times per week for 6 weeks. The deadlift and the squat were the only lower body maximal strength exercises performed by DE and SQ groups, respectively, while both training programs included jumps. A significantly (p = 0.017) greater increase in deadlift 1RM was observed in the DE compared to the SQ group, while the SQ group obtained a significantly (p = 0.049) greater increase in squat 1RM. A significant increase in jump performance (p = 0.010), without significant interactions between groups (p = 0.552), was observed in both groups. Three participants of the DE group developed lower back pain and were excluded from the study. Results indicate that both the squat and the deadlift can result in similar improvement in lower body maximal strength and jump performance and can be successfully included in strength training programs. The incidence of back pain in the DE group may suggest a marked stress of this exercise on the lower back. Proper technique should be used to minimize the risk of injury, especially when the deadlift is performed.
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Flores V, Becker J, Burkhardt E, Cotter J. Knee Kinetics During Squats of Varying Loads and Depths in Recreationally Trained Women. J Strength Cond Res 2020. [DOI: 10.1519/jsc.0000000000002509] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Murawa M, Fryzowicz A, Kabacinski J, Jurga J, Gorwa J, Galli M, Zago M. Muscle activation varies between high-bar and low-bar back squat. PeerJ 2020; 8:e9256. [PMID: 32551198 PMCID: PMC7289144 DOI: 10.7717/peerj.9256] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Accepted: 05/08/2020] [Indexed: 11/20/2022] Open
Abstract
Background Differences in the muscular activity between the high-bar back squat (HBBS) and the low-bar back squat (LBBS) on the same representative group of experienced powerlifters are still scarcely investigated. The main purpose of the study was to compare the normalized bioelectrical activity and maximal angles within single homogeneous group between the HBBS and LBBS for 60% one repetition maximum (1RM), 65% 1RM and 70% 1RM. Methods Twelve healthy men (age 24.3 ± 2.8 years, height 178.8 ± 5.6 cm, body mass 88.3 ± 11.5 kg), experienced in powerlifting performed HBBS and LBBS with comparable external loads equal 60% 1RM, 65% 1RM, and 70% 1RM. Electromyography (EMG) signals of muscle groups were synchronously recorded alongside kinematic data (joints angle) by means of a motion capture system. Results EMG activity during eccentric phase of squat motion were significantly higher during LBBS than in HBBS for all selected muscles (60% 1RM and 65% 1RM) (p < 0.05). All examined muscles were more activated during concentric phase of the squat cycle (p < 0.05). In the concentric phase, significant differences between the loads were generally not observed between just 5% 1RM change in load level for LBBS. Conclusions Our results confirmed significant differences in muscles activation between both squat techniques. Muscle activity during eccentric phase of squat motion were significantly higher during LBBS than HBBS. The differences are crucial for posterior muscle chain during eccentric phase of squat cycle.
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Affiliation(s)
- Michal Murawa
- Department of Biomechanics, Poznan University of Physical Education, Poznan, Poland
| | - Anna Fryzowicz
- Department of Biomechanics, Poznan University of Physical Education, Poznan, Poland
| | - Jaroslaw Kabacinski
- Department of Biomechanics, Poznan University of Physical Education, Poznan, Poland
| | - Jakub Jurga
- Department of Biomechanics, Poznan University of Physical Education, Poznan, Poland
| | - Joanna Gorwa
- Department of Biomechanics, Poznan University of Physical Education, Poznan, Poland
| | - Manuela Galli
- Dipartimento di Elettronica, Informazione e Bioignegneria, Politecnico di Milano, Milano, Italy
| | - Matteo Zago
- Dipartimento di Elettronica, Informazione e Bioignegneria, Politecnico di Milano, Milano, Italy
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Trindade T, de Medeiros J, Dantas P, de Oliveira Neto L, Schwade D, de Brito Vieira W, Oliveira-Dantas FF. A comparison of muscle electromyographic activity during different angles of the back and front squat. ISOKINET EXERC SCI 2020. [DOI: 10.3233/ies-193142] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Affiliation(s)
- Thiago Barbosa Trindade
- Department of Physical Education, Catholic University of Brasilia, Brasilia, Brazil
- Department of Physical Education, University Center of Rio Grande do Norte, Natal, Brazil
| | | | | | | | - Daniel Schwade
- Department of Physical Education, Federal University of Rio Grande do Norte, Natal, Brazil
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Pham RD, Machek SB, Lorenz KA. Technical Aspects and Applications of the Low-Bar Back Squat. Strength Cond J 2019. [DOI: 10.1519/ssc.0000000000000521] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Aasa U, Bengtsson V, Berglund L, Öhberg F. Variability of lumbar spinal alignment among power- and weightlifters during the deadlift and barbell back squat. Sports Biomech 2019; 21:701-717. [PMID: 31718474 DOI: 10.1080/14763141.2019.1675751] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
The aims of the study were to evaluate the relative and absolute variability of upper (T11-L2) and lower (L2-S2) lumbar spinal alignment in power- and weightlifters during the deadlift and back squat exercises, and to compare this alignment between the two lifting groups. Twenty-four competitive powerlifters (n = 14) and weightlifters (n = 10) performed three repetitions of the deadlift and the back squat exercises using a load equivalent to 70% of their respective one-repetition maximum. The main outcome measures were the three-dimensional lumbar spinal alignment for start position, minimum and maximum angle of their spinal alignment, and range of motion measured using inertial measurement units. Relative intra-trial reliability was calculated using the two-way random model intraclass correlation coefficient (ICC) and absolute reliability with minimal detectable change (MDC). The ICC ranged between 0.69 and 0.99 and the MDC between 1°-8° for the deadlift. Corresponding figures for the squat were 0.78-0.99 and 1°-6°. In all participants during both exercises, spinal adjustments were made in both thoracolumbar and lumbopelvic areas in all three dimensions. In conclusion, when performing three repetitions of the deadlift and the squat, lumbar spinal alignment of the lifters did not change much between repetitions and did not differ significantly between power- and weightlifters.
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Affiliation(s)
- Ulrika Aasa
- Department of Community Medicine and Rehabilitation, Physiotherapy, Umeå University, Umeå, Sweden
| | - Victor Bengtsson
- Department of Community Medicine and Rehabilitation, Physiotherapy, Umeå University, Umeå, Sweden
| | - Lars Berglund
- Department of Community Medicine and Rehabilitation, Sports Medicine, Umeå University, Umeå, Sweden
| | - Fredrik Öhberg
- Department of Radiation Sciences, Umeå University, Umeå, Sweden
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Glassbrook DJ, Brown SR, Helms ER, Duncan S, Storey AG. The High-Bar and Low-Bar Back-Squats: A Biomechanical Analysis. J Strength Cond Res 2019; 33 Suppl 1:S1-S18. [PMID: 28195975 DOI: 10.1519/jsc.0000000000001836] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Glassbrook, DJ, Brown, SR, Helms, ER, Duncan, S, and Storey, AG. The high-bar and low-bar back-squats: a biomechanical analysis. J Strength Cond Res 33(7S): S1-S18, 2019-No previous study has compared the joint angle and ground reaction force (vertical force [Fv]) differences between the high-bar back-squat (HBBS) and low-bar back-squat (LBBS) above 90% 1 repetition maximum (1RM). Six male powerlifters (POW) (height: 179.2 ± 7.8 cm; mass: 87.1 ± 8.0 kg; age: 21-33 years) of international level, 6 male Olympic weightlifters (OLY) (height: 176.7 ± 7.7 cm; mass: 83.1 ± 13 kg; age: 22-30 years) of national level, and 6 recreationally trained male athletes (height: 181.9 ± 8.7 cm; mass: 87.9 ± 15.3 kg; age: 23-33 years) performed the LBBS, HBBS, and both LBBS and HBBS (respectively) up to and including 100% 1RM. Small to moderate (d = 0.2-0.5) effect size differences were observed between the POW and OLY in joint angles and Fv, although none were statistically significant. However, significant joint angle results were observed between the experienced POW/OLY and the recreationally trained group. Our findings suggest that practitioners seeking to place emphasis on the stronger hip musculature should consider the LBBS. Also, when the goal is to lift the greatest load possible, the LBBS may be preferable. Conversely, the HBBS is more suited to replicate movements that exhibit a more upright torso position, such as the snatch and clean, or to place more emphasis on the associated musculature of the knee joint.
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Affiliation(s)
- Daniel J Glassbrook
- Sports Performance Research Institute New Zealand (SPRINZ), Auckland University of Technology, Auckland, New Zealand
| | - Scott R Brown
- Sports Performance Research Institute New Zealand (SPRINZ), Auckland University of Technology, Auckland, New Zealand
| | - Eric R Helms
- Sports Performance Research Institute New Zealand (SPRINZ), Auckland University of Technology, Auckland, New Zealand
| | - Scott Duncan
- Sports Performance Research Institute New Zealand (SPRINZ), Auckland University of Technology, Auckland, New Zealand
| | - Adam G Storey
- Sports Performance Research Institute New Zealand (SPRINZ), Auckland University of Technology, Auckland, New Zealand.,High Performance Sport New Zealand (HPSNZ), Auckland, New Zealand
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Comparison of Peak Ground Reaction Force, Joint Kinetics and Kinematics, and Muscle Activity Between a Flexible and Steel Barbell During the Back Squat Exercise. J Hum Kinet 2019; 68:99-108. [PMID: 31531136 PMCID: PMC6724600 DOI: 10.2478/hukin-2019-0059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The flexible barbell is purported to improve training gains compared with an Olympic steel barbell (SB) during the back squat exercise with Division I collegiate American football programs. The two bars loaded at 30% 1-repetition maximum were compared with ten trained Division I American football players (n = 10; age = 19.5 years; body mass = 89.4 kg; body height = 182.0 cm) completing 10 repetitions of the back squat exercise. Analysis included integrated-peak values of electromyography of the rectus femoris, biceps femoris, rectus abdominis, erector spinae, external oblique, vastus lateralis, ground reaction forces, and joint kinematics and kinetics of the hip, knee, and ankle. The flexible bar elicited significant increases in peak joint kinetics (Hip Moment: 229 ± 54 Nm vs. 209 ± 52 Nm; Hip Power: 494 ± 151 W vs. 382 ± 134 W; Knee Power: 305 ± 108 W vs. 241 ± 63 W), peak vertical ground reaction forces (1195 ± 209 N vs. 1120 ± 203 N), and muscle activity (Vastus Lateralis: 75.7 vs. 66.5%, Rectus Abdominis: 190 vs. 115%, Rectus Femoris: 69.8 vs. 59.9%, External Oblique: 115 vs. 69.0%). Greater vertical ground reaction forces, hip moment, hip power, knee power, and muscle activity of the vastus lateralis, rectus abdominis, rectus femoris, and external oblique suggest the FB provides biomechanical and physiological mechanisms for training gains over the SB for 30% of 1-repetition maximum loads.
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Vigotsky AD, Bryanton MA, Nuckols G, Beardsley C, Contreras B, Evans J, Schoenfeld BJ. Biomechanical, Anthropometric, and Psychological Determinants of Barbell Back Squat Strength. J Strength Cond Res 2019; 33 Suppl 1:S26-S35. [DOI: 10.1519/jsc.0000000000002535] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Pallarés JG, Cava AM, Courel-Ibáñez J, González-Badillo JJ, Morán-Navarro R. Full squat produces greater neuromuscular and functional adaptations and lower pain than partial squats after prolonged resistance training. Eur J Sport Sci 2019; 20:115-124. [PMID: 31092132 DOI: 10.1080/17461391.2019.1612952] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The choice of the optimal squatting depth for resistance training (RT) has been a matter of debate for decades and is still controversial. In this study, fifty-three resistance-trained men were randomly assigned to one of four training groups: full squat (F-SQ), parallel squat (P-SQ), half squat (H-SQ), and Control (training cessation). Experimental groups completed a 10-week velocity-based RT programme using the same relative load (linear periodization from 60% to 80% 1RM), only differing in the depth of the squat trained. The individual range of motion and spinal curvatures for each squat variation were determined in the familiarization and subsequently replicated in every lift during the training and testing sessions. Neuromuscular adaptations were evaluated by one-repetition maximum strength (1RM) and mean propulsive velocity (MPV) at each squatting depth. Functional performance was assessed by countermovement jump, 20-m sprint and Wingate tests. Physical functional disability included pain and stiffness records. F-SQ was the only group that increased 1RM and MPV in the three squat variations (ES = 0.77-2.36), and achieved the highest functional performance (ES = 0.35-0.85). P-SQ group obtained the second best results (ES = 0.15-0.56). H-SQ produced no increments in neuromuscular and functional performance (ES = -0.11-0.28) and was the only group reporting significant increases in pain, stiffness and physical functional disability (ES = 1.21-0.87). Controls declined on all tests (ES = 0.02-1.32). We recommend using F-SQ or P-SQ exercises to improve strength and functional performance in well-trained athletes. In turn, the use of H-SQ is inadvisable due to the limited performance improvements and the increments in pain and discomfort after continued training.
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Affiliation(s)
- Jesús G Pallarés
- Faculty of Sport Sciences, Human Performance and Sports Science Laboratory, University of Murcia, Murcia, Spain
| | - Alejandro M Cava
- Faculty of Sport Sciences, Human Performance and Sports Science Laboratory, University of Murcia, Murcia, Spain
| | - Javier Courel-Ibáñez
- Faculty of Sport Sciences, Human Performance and Sports Science Laboratory, University of Murcia, Murcia, Spain
| | | | - Ricardo Morán-Navarro
- Faculty of Sport Sciences, Human Performance and Sports Science Laboratory, University of Murcia, Murcia, Spain
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Reichel T, Mitnacht M, Fenwick A, Meffert R, Hoos O, Fehske K. Incidence and characteristics of acute and overuse injuries in elite powerlifters. COGENT MEDICINE 2019. [DOI: 10.1080/2331205x.2019.1588192] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
Affiliation(s)
- Thomas Reichel
- Department of Orthopaedic Trauma, Hand, Plastic and Reconstructive Surgery, University Hospital Wuerzburg, Oberduerrbacher Str. 6, 97080 Wuerzburg, Germany
| | - Martin Mitnacht
- Department of Orthopaedic Trauma, Hand, Plastic and Reconstructive Surgery, University Hospital Wuerzburg, Oberduerrbacher Str. 6, 97080 Wuerzburg, Germany
| | - Annabel Fenwick
- Department of Orthopaedic Trauma, Hand, Plastic and Reconstructive Surgery, University Hospital Wuerzburg, Oberduerrbacher Str. 6, 97080 Wuerzburg, Germany
| | - Rainer Meffert
- Department of Orthopaedic Trauma, Hand, Plastic and Reconstructive Surgery, University Hospital Wuerzburg, Oberduerrbacher Str. 6, 97080 Wuerzburg, Germany
| | - Olaf Hoos
- Center for Sports and Physical Education, University of Wuerzburg, Wuerzburg, Germany
| | - Kai Fehske
- Department of Orthopaedic Trauma, Hand, Plastic and Reconstructive Surgery, University Hospital Wuerzburg, Oberduerrbacher Str. 6, 97080 Wuerzburg, Germany
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35
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Layer JS, Grenz C, Hinshaw TJ, Smith DT, Barrett SF, Dai B. Kinetic Analysis of Isometric Back Squats and Isometric Belt Squats. J Strength Cond Res 2019; 32:3301-3309. [PMID: 30273281 DOI: 10.1519/jsc.0000000000002854] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Layer, JS, Grenz, C, Hinshaw, TJ, Smith, DT, Barrett, SF, and Dai, B. Kinetic analysis of isometric back squats and isometric belt squats. J Strength Cond Res 32(12): 3301-3309, 2018-Belt squats seem to provide an alternative to back squats. However, it is not clear how musculoskeletal loading differs between the two. This study compared lower extremity and low-back kinetics during isometric back squats and isometric belt squats. Sixteen men (age: 22.6 ± 3.4 years; height: 1.74 ± 0.11 m; mass: 82.0 ± 5.6 kg) and 10 women (age: 21.5 ± 2.5 years; height: 1.64 ± 0.10 m; mass: 68.9 ± 7.1 kg) performed isometric back squats and belt squats at 4 squat depths. Joint resultant moments were calculated from kinematic and ground reaction force data. Linear interpolation was used to estimate peak vertical forces and joint moments at a 45° thigh segment angle. Subjects increased peak forces, ankle moments, and knee moments but decreased low-back moments from back to belt squats (p ≤ 0.023). Hip moments did not significantly change between 2 squats. Subjects demonstrating smaller ankle and knee moments during back squats showed greater increases in these moments from back to belt squats (p ≤ 0.012, R ≤ 0.24). Subjects whose back squats were characterized by greater low-back moments displayed greater decreases in low-back moments from back to belt squats (p < 0.001, R = 0.98). Compared with isometric back squats, isometric belt squats may provide a similar or greater external loading for the musculoskeletal system of the lower extremities while reducing external spinal loading. Belt squats may be considered by individuals with upper-body or spinal injuries and those displaying excessive external back moments.
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Affiliation(s)
- Jacob S Layer
- Division of Kinesiology and Health, University of Wyoming, Laramie, Wyoming
| | - Christylynne Grenz
- Division of Kinesiology and Health, University of Wyoming, Laramie, Wyoming
| | - Taylour J Hinshaw
- Division of Kinesiology and Health, University of Wyoming, Laramie, Wyoming
| | - Derek T Smith
- Division of Kinesiology and Health, University of Wyoming, Laramie, Wyoming
| | - Steven F Barrett
- Department of Electrical and Computer Engineering, University of Wyoming, Laramie, Wyoming
| | - Boyi Dai
- Division of Kinesiology and Health, University of Wyoming, Laramie, Wyoming
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36
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Chapman M, Larumbe-Zabala E, Gosss-Sampson M, Colpus M, Triplett NT, Naclerio F. Perceptual, Mechanical, and Electromyographic Responses to Different Relative Loads in the Parallel Squat. J Strength Cond Res 2019; 33:8-16. [DOI: 10.1519/jsc.0000000000001867] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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37
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Martínez-Cava A, Morán-Navarro R, Sánchez-Medina L, González-Badillo JJ, Pallarés JG. Velocity- and power-load relationships in the half, parallel and full back squat. J Sports Sci 2018; 37:1088-1096. [PMID: 30426840 DOI: 10.1080/02640414.2018.1544187] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
This study aimed to compare the load-velocity and load-power relationships of three common variations of the squat exercise. 52 strength-trained males performed a progressive loading test up to the one-repetition maximum (1RM) in the full (F-SQ), parallel (P-SQ) and half (H-SQ) squat, conducted in random order on separate days. Bar velocity and vertical force were measured by means of a linear velocity transducer time-synchronized with a force platform. The relative load that maximized power output (Pmax) was analyzed using three outcome measures: mean concentric (MP), mean propulsive (MPP) and peak power (PP), while also including or excluding body mass in force calculations. 1RM was significantly different between exercises. Load-velocity and load-power relationships were significantly different between the F-SQ, P-SQ and H-SQ variations. Close relationships (R2 = 0.92-0.96) between load (%1RM) and bar velocity were found and they were specific for each squat variation, with faster velocities the greater the squat depth. Unlike the F-SQ and P-SQ, no sticking region was observed for the H-SQ when lifting high loads. The Pmax corresponded to a broad load range and was greatly influenced by how force output is calculated (including or excluding body mass) as well as the exact outcome variable used (MP, MPP, PP).
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Affiliation(s)
- Alejandro Martínez-Cava
- a Human Performance and Sports Science Laboratory. Faculty of Sport Sciences , University of Murcia , Murcia , Spain
| | - Ricardo Morán-Navarro
- a Human Performance and Sports Science Laboratory. Faculty of Sport Sciences , University of Murcia , Murcia , Spain
| | - Luis Sánchez-Medina
- b Centre for Studies, Research & Sports Medicine , Government of Navarre , Pamplona , Spain
| | | | - Jesús G Pallarés
- a Human Performance and Sports Science Laboratory. Faculty of Sport Sciences , University of Murcia , Murcia , Spain
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38
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Laza-Cagigas R, Goss-Sampson M, Larumbe-Zabala E, Termkolli L, Naclerio F. Validity and reliability of a novel optoelectronic device to measure movement velocity, force and power during the back squat exercise. J Sports Sci 2018; 37:795-802. [DOI: 10.1080/02640414.2018.1527673] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Affiliation(s)
| | - Mark Goss-Sampson
- Department of Life and Sport Science, University of Greenwich, New Eltham, UK
| | | | - Leke Termkolli
- Department of Life and Sport Science, University of Greenwich, New Eltham, UK
| | - Fernando Naclerio
- Department of Life and Sport Science, University of Greenwich, New Eltham, UK
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39
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Lorenzetti S, Ostermann M, Zeidler F, Zimmer P, Jentsch L, List R, Taylor WR, Schellenberg F. How to squat? Effects of various stance widths, foot placement angles and level of experience on knee, hip and trunk motion and loading. BMC Sports Sci Med Rehabil 2018; 10:14. [PMID: 30026952 PMCID: PMC6050697 DOI: 10.1186/s13102-018-0103-7] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2017] [Accepted: 06/25/2018] [Indexed: 11/23/2022]
Abstract
Background Squatting is a core exercise for many purposes. The tissue loading during squatting is crucial for positive adaptation and to avoid injury. This study aimed to evaluate the effect of narrow, hip and wide stance widths, foot position angles (0°, 21°, and 42°), strength exercise experience, and barbell load (0 and 50% body weight, experts only) during squatting. Methods Novice (N = 21) and experienced (N = 21) squatters performed 9 different variations of squats (3 stance widths, 3 foot placement angles). A 3D motion capture system (100 Hz) and two force plates (2000 Hz) were used to record mediolateral knee displacement (ΔD*), range of motion (RoM) at the hip and knee joints, and joint moments at the hip, knee, and lower back. Results Both stance width and foot placement angles affected the moments at the hip and knee joints in the frontal and sagittal planes. ΔD* varied with stance width, foot placement angles and between the subjects’ level of experience with the squat exercise as follows: increasing foot angle led to an increased foot angle led to an increased ΔD*, while an increased stance width resulted in a decreased ΔD*; novice squatters showed a higher ΔD*, while additional weight triggered a decreased ΔD*. Conclusions Suitable stance width and foot placement angles should be chosen according to the targeted joint moments. In order to avoid injury, special care should be taken in extreme positions (narrow stand-42° and wide stance-0°) where large knee and hips joint moments were observed. Electronic supplementary material The online version of this article (10.1186/s13102-018-0103-7) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Silvio Lorenzetti
- 1Institute for Biomechanics, ETH Zurich, Leopold-Ruzicka-Weg 4, 8093 Zürich, Switzerland.,2Swiss Federal Institute of Sport Magglingen, SFISM, Hauptstrasse 247, 2532 Magglingen, Switzerland
| | - Mira Ostermann
- 1Institute for Biomechanics, ETH Zurich, Leopold-Ruzicka-Weg 4, 8093 Zürich, Switzerland.,3Department of Business, Health & Social Work, Bern University of Applied Science, Schwarztorstrasse 48, 3007 Bern, Switzerland
| | - Fabian Zeidler
- 1Institute for Biomechanics, ETH Zurich, Leopold-Ruzicka-Weg 4, 8093 Zürich, Switzerland.,4Department of Medicine, Sports & Healthcare, University of Applied Science Technikum Vienna, Höchstädtplatz 6, 1200 Wien, Austria
| | - Pia Zimmer
- 1Institute for Biomechanics, ETH Zurich, Leopold-Ruzicka-Weg 4, 8093 Zürich, Switzerland.,4Department of Medicine, Sports & Healthcare, University of Applied Science Technikum Vienna, Höchstädtplatz 6, 1200 Wien, Austria
| | - Lina Jentsch
- 1Institute for Biomechanics, ETH Zurich, Leopold-Ruzicka-Weg 4, 8093 Zürich, Switzerland
| | - Renate List
- 1Institute for Biomechanics, ETH Zurich, Leopold-Ruzicka-Weg 4, 8093 Zürich, Switzerland
| | - William R Taylor
- 1Institute for Biomechanics, ETH Zurich, Leopold-Ruzicka-Weg 4, 8093 Zürich, Switzerland
| | - Florian Schellenberg
- 1Institute for Biomechanics, ETH Zurich, Leopold-Ruzicka-Weg 4, 8093 Zürich, Switzerland
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40
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Bengtsson V, Berglund L, Aasa U. Narrative review of injuries in powerlifting with special reference to their association to the squat, bench press and deadlift. BMJ Open Sport Exerc Med 2018; 4:e000382. [PMID: 30057777 PMCID: PMC6059276 DOI: 10.1136/bmjsem-2018-000382] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/25/2018] [Indexed: 11/17/2022] Open
Abstract
Pain and injuries are considered a common problem among elite athletes and recreational lifters performing the squat, bench press and deadlift. Since all three lifts engage multiple joints and expose the lifters’ bodies to high physical demands often several times a week, it has been suggested that their injuries might be related to the excessively heavy loads, the large range of motion during the exercises, insufficient resting times between training sessions and/or faulty lifting technique. However, no previous article has summarised what is known about specific injuries and the injury aetiology associated with the three lifts. Thus, the aim of this narrative review was to summarise what is known about the relationships between the powerlifting exercises and the specific injuries or movement impairments that are common among lifters and recreationally active individuals.
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Affiliation(s)
- Victor Bengtsson
- Department of Community Medicine and Rehabilitation, Physiotherapy, Umeå University, Umeå, Sweden
| | - Lars Berglund
- Department of Community Medicine and Rehabilitation, Physiotherapy, Umeå University, Umeå, Sweden.,Umeå School of Sport Sciences, Umeå University, Umeå, Sweden
| | - Ulrika Aasa
- Department of Community Medicine and Rehabilitation, Physiotherapy, Umeå University, Umeå, Sweden.,Umeå School of Sport Sciences, Umeå University, Umeå, Sweden.,Medfit, Primary Care Rehabilitation and Fitness Centre, Stockholm, Sweden
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41
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Abstract
BACKGROUND Weight-training sports, including weightlifting, powerlifting, bodybuilding, strongman, Highland Games, and CrossFit, are weight-training sports that have separate divisions for males and females of a variety of ages, competitive standards, and bodyweight classes. These sports may be considered dangerous because of the heavy loads commonly used in training and competition. OBJECTIVES Our objective was to systematically review the injury epidemiology of these weight-training sports, and, where possible, gain some insight into whether this may be affected by age, sex, competitive standard, and bodyweight class. METHODS We performed an electronic search using PubMed, SPORTDiscus, CINAHL, and Embase for injury epidemiology studies involving competitive athletes in these weight-training sports. Eligible studies included peer-reviewed journal articles only, with no limit placed on date or language of publication. We assessed the risk of bias in all studies using an adaption of the musculoskeletal injury review method. RESULTS Only five of the 20 eligible studies had a risk of bias score ≥75 %, meaning the risk of bias in these five studies was considered low. While 14 of the studies had sample sizes >100 participants, only four studies utilized a prospective design. Bodybuilding had the lowest injury rates (0.12-0.7 injuries per lifter per year; 0.24-1 injury per 1000 h), with strongman (4.5-6.1 injuries per 1000 h) and Highland Games (7.5 injuries per 1000 h) reporting the highest rates. The shoulder, lower back, knee, elbow, and wrist/hand were generally the most commonly injured anatomical locations; strains, tendinitis, and sprains were the most common injury type. Very few significant differences in any of the injury outcomes were observed as a function of age, sex, competitive standard, or bodyweight class. CONCLUSION While the majority of the research we reviewed utilized retrospective designs, the weight-training sports appear to have relatively low rates of injury compared with common team sports. Future weight-training sport injury epidemiology research needs to be improved, particularly in terms of the use of prospective designs, diagnosis of injury, and changes in risk exposure.
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Affiliation(s)
- Justin W L Keogh
- Faculty of Health Sciences and Medicine, Bond University, Gold Coast, QLD, Australia. .,Sports Performance Research Institute New Zealand (SPRINZ), AUT Millennium, AUT University, Auckland, New Zealand. .,Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, Sippy Downs, QLD, Australia.
| | - Paul W Winwood
- Sports Performance Research Institute New Zealand (SPRINZ), AUT Millennium, AUT University, Auckland, New Zealand.,Department of Sport and Recreation, School of Applied Science, Bay of Plenty Polytechnic, Tauranga, New Zealand
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42
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Fuglsang EI, Telling AS, Sørensen H. Effect of Ankle Mobility and Segment Ratios on Trunk Lean in the Barbell Back Squat. J Strength Cond Res 2018; 31:3024-3033. [PMID: 28301442 DOI: 10.1519/jsc.0000000000001872] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Fuglsang, EI, Telling, AS, and Sørensen, H. Effect of ankle mobility and segment ratios on trunk lean in the barbell back squat. J Strength Cond Res 31(11): 3024-3033, 2017-The barbell back squat is a popular exercise used for both performance enhancing and rehabilitation purposes. However, injuries are common, and people with a history of lower back pain are especially vulnerable. Past studies have shown that higher trunk angles (less forward lean) generate less stress on the lower back; thus, it seems appropriate to investigate the factors presumed to influence the trunk angle. Therefore, the aim of this study was to investigate how ankle mobility and the segment ratios between the thoracic spine, thighs, and shanks influence the trunk angle in the back squat. While recorded with motion capture, 11 male subjects performed 3 repetitions at approximately 75% of 1 repetition maximum in the squat to a parallel position (thighs horizontal) or lower. Furthermore, subjects performed a weight bearing lunge test to determine maximal range of motion (ROM) of the ankle joint. Segment angles of the shank, thigh, and trunk segments as well as ankle joint angles were calculated by 2-dimensional kinematic analysis. Simple linear and multiple regressions were used to test the correlation between the lower extremity angles, segment ratios, and the trunk angle. On average, subjects had an 11.4 ± 4.4° deficit in dorsiflexion ROM between maximal ROM and ROM in the parallel squat (PS) which was independent of maximal ROM. Ankle mobility showed to significantly negatively correlate with trunk angle, thereby showing that a subject with greater ankle ROM had a more upright torso in the PS position. This study was unable to find a significant correlation between the segment ratios and trunk angle. Furthermore, when combined, no significant relationship between ankle mobility, segment length ratios, and trunk angle were found, although it was noticed that this more complex model showed the greatest R value.
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Affiliation(s)
- Emil I Fuglsang
- Department of Sport Science, Aarhus University, Aarhus, Denmark
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43
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Effects of Knee Position on the Reliability and Production of Maximal and Rapid Strength Characteristics During an Isometric Squat Test. J Appl Biomech 2018; 34:111-117. [PMID: 29017410 DOI: 10.1123/jab.2017-0213] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
This study aimed to examine the effects of knee position on the reliability and production of peak force (PF) and rate of force development (RFD) characteristics during an isometric squat. Fourteen resistance-trained females performed isometric squats at 90, 120, and 150° knee angles (corresponding to parallel, half, and quarter squat positions, respectively) on 2 different occasions, from which PF, peak RFD, and early (RFD30, RFD50, RFD100) and late (RFD200) phase RFD variables were extracted. PF and RFD200 were highly consistent across trials for all 3 squat positions, with intraclass correlation coefficients (ICCs) ranging between 0.812-0.904 and coefficients of variation (CVs) between 6.6-19.4%. For peak and early RFD characteristics, higher ICCs and lower CV values were observed for the quarter squat (ICCs = 0.818-0.852, CVs = 17.3-19.4%) compared to the parallel (ICCs = 0.591-0.649, CVs = 30.1-55.9%) and half squats (ICCs = 0.547-0.598,CVs = 31.1-34.2%). In addition, isometric PF and RFD200 increased (P ≤ .001-0.04) with squat position (parallel < half < quarter); however, there were no differences for peak RFD (P ≥ .27), RFD30 (P ≥ .99), RFD50 (P ≥ .99), and RFD100 (P ≥ .09). These findings suggest that performing isometric squats at higher (150°) rather than lower knee joint angles (90-120°) may provide for an improved capacity to produce greater PF and RFD200 as well as a more reliable testing position for measuring peak and early RFD characteristics.
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Glassbrook DJ, Helms ER, Brown SR, Storey AG. A Review of the Biomechanical Differences Between the High-Bar and Low-Bar Back-Squat. J Strength Cond Res 2018; 31:2618-2634. [PMID: 28570490 DOI: 10.1519/jsc.0000000000002007] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Glassbrook, DJ, Helms, ER, Brown, SR, and Storey, AG. A review of the biomechanical differences between the high-bar and low-bar back-squat. J Strength Cond Res 31(9): 2618-2634, 2017-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 2 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 used 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 (a) joint angles, (b) vertical ground reaction forces, and (c) 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 a 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 use the LBBS. In comparison, those seeking to replicate movements with a more upright torso and contribution from the quadriceps may rather seek to use the HBBS in training.
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Affiliation(s)
- Daniel J Glassbrook
- 1Sports Performance Research Institute New Zealand (SPRINZ), Auckland University of Technology, Auckland, New Zealand; and 2High Performance Sport New Zealand (HPSNZ), Auckland, New Zealand
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Naclerio F, Larumbe-Zabala E. Relative Load Prediction by Velocity and the OMNI-RES 0-10 Scale in Parallel Squat. J Strength Cond Res 2017; 31:1585-1591. [PMID: 28538309 DOI: 10.1519/jsc.0000000000001601] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
This study analyzed the possibility of using movement velocity and the rate of perceived exertion as predictors of relative load in the parallel squat (PSQ) exercise. To determine the full load-velocity and load-rate of perceived exertion relationships, 290 young, resistance-trained athletes (209 males and 81 females) performed a progressive strength test up to the 1 repetition maximum. Longitudinal regression models were used to predict the relative load from the average velocity (AV) and the OMNI-RES 0-10 scale, considering sets as the time-related variable. Two adjusted predictive equations were developed from the association between the relative load and the AV or the rate of perceived exertion expressed after performing several sets of 1-3 repetitions during the progressive test. The resulting 2 models were capable of estimating the relative load with an accuracy of 79 and 86% for the AV (relative load [% 1 repetition maximum, RM] = 120.15-83.54 [AV]) and the exertion (relative load [% 1RM] = 5.07 + 9.63 [rate of perceived exertion]), respectively. The strong association between relative load with AV and the rate of perceived exertion supports the use of both predictive variables to estimate strength performance in PSQ.
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Affiliation(s)
- Fernando Naclerio
- 1Department of Life and Sports Science, University of Greenwich, Medway, Kent, United Kingdom; and 2Clinical Research Institute, Texas Tech University HSC, Lubbock, Texas
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Charlton JM, Hammond CA, Cochrane CK, Hatfield GL, Hunt MA. The Effects of a Heel Wedge on Hip, Pelvis and Trunk Biomechanics During Squatting in Resistance Trained Individuals. J Strength Cond Res 2017; 31:1678-1687. [DOI: 10.1519/jsc.0000000000001655] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Sánchez-Medina L, Pallarés JG, Pérez CE, Morán-Navarro R, González-Badillo JJ. Estimation of Relative Load From Bar Velocity in the Full Back Squat Exercise. Sports Med Int Open 2017; 1:E80-E88. [PMID: 30539090 PMCID: PMC6226068 DOI: 10.1055/s-0043-102933] [Citation(s) in RCA: 135] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Revised: 01/19/2017] [Accepted: 01/25/2017] [Indexed: 11/08/2022] Open
Abstract
The use of bar velocity to estimate relative load in the back squat exercise was examined. 80 strength-trained men performed a progressive loading test to determine their one-repetition maximum (1RM) and load-velocity relationship. Mean (MV), mean propulsive (MPV) and peak (PV) velocity measures of the concentric phase were analyzed. Both MV and MPV showed a very close relationship to %1RM (R
2
=0.96), whereas a weaker association (R
2
=0.79) and larger SEE (0.14 vs. 0.06 m·s
−1
) were found for PV. Prediction equations to estimate load from velocity were obtained. When dividing the sample into 3 groups of different relative strength (1RM/body mass), no differences were found between groups for the MPV attained against each %1RM. MV attained with the 1RM was 0.32±0.03 m·s
−1
. The propulsive phase accounted for ~82% of concentric duration at 40% 1RM, and progressively increased until reaching 100% at 1RM. Provided that repetitions are performed at maximal intended velocity, a good estimation of load (%1RM) can be obtained from mean velocity as soon as the first repetition is completed. This finding provides an alternative to the often demanding, time-consuming and interfering 1RM or nRM tests and allows implementing a velocity-based resistance training approach.
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Affiliation(s)
- Luis Sánchez-Medina
- Instituto Navarro de Deporte y Juventud (INDJ), Studies, Research and Sports Medicine Centre, Pamplona, Spain
| | - Jesús G Pallarés
- University of Murcia, Human Performance and Sports Science Laboratory, Murcia, Spain
| | - Carlos E Pérez
- University of Murcia, Sports Medicine Centre, Murcia, Spain
| | - Ricardo Morán-Navarro
- University of Murcia, Human Performance and Sports Science Laboratory, Murcia, Spain
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Todoroff M. Dynamic Deep Squat: Lower-Body Kinematics and Considerations Regarding Squat Technique, Load Position, and Heel Height. Strength Cond J 2017. [DOI: 10.1519/ssc.0000000000000278] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Muscle group specific changes in the electromechanical delay following short-term resistance training. J Sci Med Sport 2016; 19:761-5. [DOI: 10.1016/j.jsams.2015.11.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2015] [Revised: 10/12/2015] [Accepted: 11/05/2015] [Indexed: 11/24/2022]
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Chiu LZF, vonGaza GL, Jean LMY. Net joint moments and muscle activation in barbell squats without and with restricted anterior leg rotation. J Sports Sci 2016; 35:35-43. [DOI: 10.1080/02640414.2016.1154978] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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