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Bengtsson V, Berglund L, Öhberg F, Aasa U. Thoracolumbar and Lumbopelvic Spinal Alignment During the Barbell Back Squat: A Comparison Between Men and Women. Int J Sports Phys Ther 2023; 18:820-830. [PMID: 37547841 PMCID: PMC10399085 DOI: 10.26603/001c.83942] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Accepted: 06/16/2023] [Indexed: 08/08/2023] Open
Abstract
Background Maintaining neutral spinal alignment is considered important when performing the barbell back squat exercise. Since male and female lifters may differ in injury location it is important to examine whether they differ in spinal alignment during the back squat. Objectives The study aimed to quantify the spinal alignment in the upper and lower lumbar spine during the barbell back squat exercise in male and female lifters. Secondary aims were to compare alignment during the back squat to standing habitual lumbar spine alignment and determine whether male and female lifters differ in these aspects. Study Design Observational, Cross-sectional. Methods Competitive power- and weightlifters were recruited and performed three repetitions of the barbell back squat exercise using a load equivalent to 70% of their one-repetition maximum. Spinal alignment and range of motion were measured using inertial measurement units placed on the thoracic, lumbar and sacral spine. Data was presented descriptively and comparisons between men and women as well as spinal alignment in four different positions were done with a factorial repeated measures analysis of variance. Results Twenty-three (14 males, 9 females) were included. During execution of the squat, spinal alignment adjustments in the lumbar spine were made in all three planes of movement, compared to the start position, in both male and female lifters. Compared to their standing habitual posture, all lifters adjusted their upper lumbar spine to a less lordotic position when in the start position of the back squat (standing upright with the barbell on their back). Only male lifters assumed a less lordotic alignment in their lower lumbar spine in the start position compared their habitual posture. Conclusions Adjustments of spinal alignment, predominantly in the sagittal plane, are made during execution of the back squat in both male and female lifters. Further, lifters adopt a less lordotic alignment with a heavy barbell on their upper back, more so in male than female lifters. In conclusion, it seems that spinal alignment changes noticeably during the barbell back squat. Level of Evidence 3©The Author(s).
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Affiliation(s)
| | - Lars Berglund
- Community medicine and rehabilitation Umeå university
| | | | - Ulrika Aasa
- Community medicine and rehabilitation Umeå university
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Bengtsson V, Aasa U, Öhberg F, Berglund L. Thoracolumbar And Lumbopelvic Spinal Alignment During The Deadlift Exercise: A Comparison Between Men And Women. Int J Sports Phys Ther 2022; 17:1063-1074. [PMID: 36237649 PMCID: PMC9528690 DOI: 10.26603/001c.37859] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Accepted: 05/20/2022] [Indexed: 11/18/2022] Open
Abstract
Background A neutral spinal alignment is considered important during the execution of the deadlift exercise to decrease the risk of injury. Since male and female powerlifters experience pain in different parts of their backs, it is important to examine whether men and women differ in spinal alignment during the deadlift. Objectives The purpose of this study was to quantify the spinal alignment in the upper (thoracolumbar, T11-L2) and lower (lumbopelvic, L2-S2) lumbar spine during the deadlift exercise in male and female lifters. Secondary aims were to compare lumbar spine alignment during the deadlift to standing habitual posture, and determine whether male and female lifters differ in these aspects. Study Design Observational, Cross-sectional. Methods Twenty-four (14 men, 10 women) lifters performed three repetitions of the deadlift exercise using 70% of their respective one-repetition maximum. Spinal alignment and spinal range of motion were measured using three inertial measurement units placed on the thoracic, lumbar and sacral spine. Data from three different positions were analyzed; habitual posture in standing, and start and stop positions of the deadlift, i.e. bottom and finish position respectively. Results During the deadlift, spinal adjustments were evident in all three planes of movement. From standing habitual posture to the start position the lumbar lordosis decreased 13° in the upper and 20° in the lower lumbar spine. From start position to stop position the total range of motion in the sagittal plane was 11° in the upper and 22° in the lower lumbar spine. The decreased lumbar lordosis from standing habitual posture to the start position was significantly greater among men. Conclusions Men and women adjust their spinal alignment in all three planes of movement when performing a deadlift and men seem to make greater adjustments from their standing habitual posture to start position in the sagittal plane. Level of Evidence 3.
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Affiliation(s)
| | - Ulrika Aasa
- Community medicine and rehabilitation, Umeå university
| | | | - Lars Berglund
- Community medicine and rehabilitation, Umeå university
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Ramirez VJ, Bazrgari B, Gao F, Samaan M. Low Back Biomechanics during Repetitive Deadlifts: A Narrative Review. IISE Trans Occup Ergon Hum Factors 2022. [PMID: 34875981 DOI: 10.1080/24725838.2021.2015642] [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] [Indexed: 10/18/2022]
Abstract
OCCUPATIONAL APPLICATIONSHeavy deadlifting is used as a screening tool or training protocol for recruitment and retention in physically-demanding occupations, especially in the military. Spinal loads experienced during heavy deadlifts, particularly shearing forces, are well above recommended thresholds for lumbar spine injury in occupational settings. Although members of the noted occupation likely have stronger musculoskeletal systems compared to the general population, experiencing shearing forces that are 2 to 4 times larger than the threshold of injury, particularly under repetitive deadlift, may transform a screening tool or training protocol to an occupationally-harmful physical activity.
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Affiliation(s)
| | - Babak Bazrgari
- Biomedical Engineering, University of Kentucky, Lexington, KY, USA
| | - Fan Gao
- Biomedical Engineering, University of Kentucky, Lexington, KY, USA
| | - Michael Samaan
- Biomedical Engineering, University of Kentucky, Lexington, KY, USA
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Footwear Affects Conventional and Sumo Deadlift Performance. Sports (Basel) 2021; 9:sports9020027. [PMID: 33670253 PMCID: PMC7918349 DOI: 10.3390/sports9020027] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Revised: 01/27/2021] [Accepted: 02/08/2021] [Indexed: 11/16/2022] Open
Abstract
Barefoot weightlifting has become a popular training modality in recent years due to anecdotal suggestions of improved performance. However, research to support these anecdotal claims is limited. Therefore, the purpose of this study was to assess the differences between the conventional deadlift (CD) and the sumo deadlift (SD) in barefoot and shod conditions. On day one, one-repetition maximums (1 RM) were assessed for thirty subjects in both the CD and SD styles. At least 72 h later, subjects returned to perform five repetitions in four different conditions (barefoot and shod for both CD and SD) at 70% 1 RM. A 2 × 2 (footwear × lifting style) MANOVA was used to assess differences between peak vertical ground reaction force (VGRF), total mechanical work (WORK), barbell vertical displacement (DISP), peak vertical velocity (PV) and lift time (TIME) during the concentric phase. The CD displayed significant increases in VGRF, DISP, WORK, and TIME over the SD. The shod condition displayed increased WORK, DISP, and TIME compared to the barefoot condition. This study suggests that lifting barefoot does not improve performance as no differences in VGRF or PV were evident. The presence of a shoe does appear to increase the DISP and WORK required to complete the lift, suggesting an increased work load is present while wearing shoes.
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Snarr RL, Adams K, Cook J. Exercise Technique: Hexagonal Bar Romanian Deadlift. Strength Cond J 2021. [DOI: 10.1519/ssc.0000000000000571] [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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6
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Holmes CJ. UNDERSTANDING THE DEADLIFT AND ITS VARIATIONS. ACSM'S HEALTH & FITNESS JOURNAL 2020. [DOI: 10.1249/fit.0000000000000570] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Wilson MT, Ryan AMF, Vallance SR, Dias-Dougan A, Dugdale JH, Hunter AM, Hamilton DL, Macgregor LJ. Tensiomyography Derived Parameters Reflect Skeletal Muscle Architectural Adaptations Following 6-Weeks of Lower Body Resistance Training. Front Physiol 2019; 10:1493. [PMID: 31920699 PMCID: PMC6914863 DOI: 10.3389/fphys.2019.01493] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Accepted: 11/21/2019] [Indexed: 01/01/2023] Open
Abstract
Measurement of muscle specific contractile properties in response to resistance training (RT) can provide practitioners valuable information regarding physiological status of individuals. Field based measurements of such contractile properties within specific muscle groups, could be beneficial when monitoring efficacy of training or rehabilitation interventions. Tensiomyography (TMG) quantifies contractile properties of individual muscles via an electrically stimulated twitch contraction and may serve as a viable option in the aforementioned applications. Thus, aims of this study were; (i) to investigate the potential use of TMG to quantify training adaptations and differences, in response to exercise specific lower limb RT; and (ii) investigate any associations between TMG parameters and accompanying muscle architectural measures. Non-resistance trained male participants (n = 33) were randomly assigned to 1 of 3 single-exercise intervention groups (n = 11 per group); back squat (BS), deadlift (DL), or hip thrust (HT). Participants completed a 6-week linearized training program (2× per week), where the assigned exercise was the sole method of lower body training. Pre- and post-intervention testing of maximal dynamic strength was assessed by one repetition maximum (1RM) of BS, DL, and HT. Radial muscle belly displacement (Dm) and contraction time (Tc) were obtained via TMG from the rectus femoris (RF) and vastus lateralis (VL) pre- and post-intervention, alongside muscle architectural measures (pennation angle and muscle thickness). All three groups displayed significant increases all 1RM strength tests (p < 0.001; pη2 = 0.677-0.753). Strength increases were accompanied by significant overall increases in RF muscle thickness (p < 0.001, pη2 = 0.969), and pennation angle (p = 0.007, pη2 = 0.220). Additionally, an overall reduction in RF Dm (p < 0.001, pη2 = 0.427) was observed. Significant negative relationships were observed between RF Dm and pennation angle (p = 0.003, r = -0.36), and with RF Dm and muscle thickness (p < 0.001, r = -0.50). These findings indicate that TMG is able to detect improved contractile properties, alongside improvements in muscle function within an untrained population. Furthermore, the observed associations between Dm and muscle architecture suggest that TMG contractile property assessments could be used to obtain information on muscle geometry.
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Affiliation(s)
- Matthew T. Wilson
- Physical Exercise and Nutrition Research Group, Faculty of Health Sciences and Sport, University of Stirling, Stirling, United Kingdom
| | - Andrew M. F. Ryan
- Physical Exercise and Nutrition Research Group, Faculty of Health Sciences and Sport, University of Stirling, Stirling, United Kingdom
| | - Scott R. Vallance
- Physical Exercise and Nutrition Research Group, Faculty of Health Sciences and Sport, University of Stirling, Stirling, United Kingdom
| | - Alastair Dias-Dougan
- Physical Exercise and Nutrition Research Group, Faculty of Health Sciences and Sport, University of Stirling, Stirling, United Kingdom
| | - James H. Dugdale
- Physical Exercise and Nutrition Research Group, Faculty of Health Sciences and Sport, University of Stirling, Stirling, United Kingdom
| | - Angus M. Hunter
- Physical Exercise and Nutrition Research Group, Faculty of Health Sciences and Sport, University of Stirling, Stirling, United Kingdom
| | - D. Lee Hamilton
- School of Exercise and Nutrition Sciences, Institute for Physical Activity and Nutrition, Deakin University, Geelong, VIC, Australia
| | - Lewis J. Macgregor
- Physical Exercise and Nutrition Research Group, Faculty of Health Sciences and Sport, University of Stirling, Stirling, United Kingdom
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Whelan D, Delahunt E, O'Reilly M, Hernandez B, Caulfield B. Determining Interrater and Intrarater Levels of Agreement in Students and Clinicians When Visually Evaluating Movement Proficiency During Screening Assessments. Phys Ther 2019; 99:478-486. [PMID: 30657981 DOI: 10.1093/ptj/pzz004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/12/2017] [Accepted: 08/31/2018] [Indexed: 11/13/2022]
Abstract
BACKGROUND Biomechanical screening assessments are used to provide useful information about an athlete's movement proficiency. Clinically, movement proficiency is typically evaluated visually. This can result in low levels of agreement, leading to difficulties in ensuring consistent athlete assessment. OBJECTIVE The objective was to determine levels of agreement within and between physical therapists and physical therapist students when visually evaluating athletes' movement proficiency during biomechanical screening assessments. DESIGN This was an observational study. METHODS Twenty-seven physical therapists and 20 physical therapist students assessed 100 video recordings of athletes performing 4 lower-extremity biomechanical screening assessments: squat, lunge, single leg squat, and deadlift. Analysis was completed on conditioned and unconditioned data. In the conditioned data, technique deviations were induced purposefully by the athletes. In the unconditioned data, deviations occurred naturally due to increased weight or movement complexity. In order to determine levels of agreement in the assessments, participants were required to classify the athletes' movement as acceptable or aberrant. Each participant assessed the same video recordings on 2 separate occasions at least 30 days apart. Agreement levels were determined using Cohen κ and Fleiss κ. RESULTS Kappa scores at an interrater level ranged from 0.18 to 0.53, and intrarater agreement ranged from 0.38 to 0.62. Levels of agreement were higher in the conditioned data compared with the unconditioned data. Overall, the lunge and squat produced higher levels of agreement than the deadlift and single-leg squat. Students and physical therapists demonstrated similar levels of agreement. LIMITATIONS Screening assessments were evaluated through the use of video analysis. CONCLUSIONS Greater efforts are needed to ensure standardization of movement analysis.
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Affiliation(s)
- Darragh Whelan
- Insight Centre for Data Analytics, University College Dublin; and School of Public Health, Physiotherapy and Sports Science, University College Dublin, Science Centre East, Belfield, Dublin, Ireland
| | - Eamonn Delahunt
- School of Public Health, Physiotherapy and Sports Science, University College Dublin
| | - Martin O'Reilly
- Insight Centre for Data Analytics; and School of Public Health, Physiotherapy and Sports Science, University College Dublin
| | | | - Brian Caulfield
- Insight Centre for Data Analytics; and School of Public Health, Physiotherapy and Sports Science, University College Dublin
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Lockie RG, Moreno MR, Orjalo AJ, Lazar A, Liu TM, Stage AA, Birmingham-Babauta SA, Stokes JJ, Giuliano DV, Risso FG, Davis DL, Callaghan SJ. Relationships Between Height, Arm Length, and Leg Length on the Mechanics of the Conventional and High-Handle Hexagonal Bar Deadlift. J Strength Cond Res 2019; 32:3011-3019. [PMID: 29045317 DOI: 10.1519/jsc.0000000000002256] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Lockie, RG, Moreno, MR, Orjalo, AJ, Lazar, A, Liu, TM, Stage, AA, Birmingham-Babauta, SA, Stokes, JJ, Giuliano, DV, Risso, FG, Davis, DL, and Callaghan, SJ. Relationships between height, arm length, and leg length on the mechanics of the conventional and high-handle hexagonal bar deadlift. J Strength Cond Res 32(11): 3011-3019, 2018-The study investigated relationships between arm length (AL) and leg length (LL) and conventional deadlift (CD) and high-handle hexagonal bar deadlift (HHBD) mechanics. Twenty-three resistance-trained subjects (14 men and 9 women) completed a 1 repetition maximum CD and HHBD. A linear position transducer was used to measure lift distance and duration; peak and mean power, velocity, and force; time to peak power and velocity; and work. Right AL and LL were measured, and AL-to-LL ratio (AL:LL) was also calculated. Spearman's correlations (ρ; p ≤ 0.05) computed relationships between anthropometry and deadlift mechanics separately for men and women. For the HHBD, greater height and LL related to greater lift distance and work (ρ = 0.54-0.68); a higher AL:LL related to time to peak power and velocity occurring sooner (ρ = -0.67 to 0.78). For the HHBD, greater height and LL related to greater lift distance and work; a higher AL:LL related to time to peak power and velocity occurring sooner in the lift (ρ = 0.54-0.77). In women, greater height, AL, and LL related to a longer CD lift distance (ρ = 0.67-0.92). For the HHBD, greater height, AL, and LL related to a longer lift distance and greater mean velocity (ρ = 0.69-0.96). There was a negative relationship between AL and lift time (ρ = -0.83), which meant longer arms resulted in a lower HHBD lift time. Arm length may have influenced women more because of the fixed dimensions of the hexagonal bar. Coaches should be cognizant of potential differences in CD and HHBD work when performed by individuals of different body sizes.
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Affiliation(s)
- Robert G Lockie
- Department of Kinesiology, California State University, Fullerton, Fullerton, CA
| | - Matthew R Moreno
- Department of Kinesiology, California State University, Fullerton, Fullerton, CA
| | - Ashley J Orjalo
- Department of Kinesiology, California State University, Fullerton, Fullerton, CA
| | - Adrina Lazar
- Department of Kinesiology, California State University, Northridge, Northridge, CA
| | - Tricia M Liu
- Department of Kinesiology, California State University, Northridge, Northridge, CA
| | - Alyssa A Stage
- Department of Kinesiology, California State University, Northridge, Northridge, CA
| | | | - John J Stokes
- Department of Kinesiology, California State University, Northridge, Northridge, CA
| | - Dominic V Giuliano
- Department of Kinesiology, California State University, Northridge, Northridge, CA
| | - Fabrice G Risso
- Department of Kinesiology, California State University, Fullerton, Fullerton, CA
| | - DeShaun L Davis
- Department of Kinesiology, California State University, Fullerton, Fullerton, CA
| | - Samuel J Callaghan
- Center for Exercise and Sport Science, School of Exercise and Health Sciences, Edith Cowan University, Joondalup, Australia
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Edington C, Greening C, Kmet N, Philipenko N, Purves L, Stevens J, Lanovaz J, Butcher S. The Effect of Set Up Position on EMG Amplitude, Lumbar Spine Kinetics, and Total Force Output During Maximal Isometric Conventional-Stance Deadlifts. Sports (Basel) 2018; 6:sports6030090. [PMID: 30200300 PMCID: PMC6162543 DOI: 10.3390/sports6030090] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2018] [Revised: 08/28/2018] [Accepted: 08/29/2018] [Indexed: 11/16/2022] Open
Abstract
The purpose of this study was to examine the biomechanical differences between two set up variations during the isometric initiation of conventional barbell deadlifts (DL): Close-bar DL (CBDL), where the bar is positioned above the navicular, and far-bar DL (FBDL), where the bar is placed above the 3rd metatarsophalangeal joint. A cross-sectional, randomized, within-participant pilot study was used. Experienced powerlifters and weightlifters (n = 10) performed three individual isometric pulls of the initiation of both conditions. The CBDL resulted in lower tibia and knee angles and greater pelvis and torso angles than the FBDL (p < 0.05), as well as greater electromyography (EMG) activity in the biceps femoris and upper lumbar erector spinae, but lower activity in the vastus lateralis, and a lower knee extensor moment (p < 0.05). There were no statistical differences for ground reaction force, joint reaction lumbar shear and compression forces between the two conditions. Despite the differences in pelvis and torso angles between lifting conditions, the internal joint net moment, internal shear forces, and internal compressive forces were not different between the two lifting styles. The CBDL set up also resulted in greater posterior chain (hamstrings and erector spine) EMG amplitude, whereas the FBDL set up resulted in more anterior chain (quadriceps) amplitude. Lifters and coaches may choose either deadlift style, according to preferences or training goals, without concern for differences in lumbar spinal loading.
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Affiliation(s)
- Corey Edington
- College of Kinesiology, University of Saskatchewan, Saskatoon, SK S7N 5B2, Canada.
| | - Cassandra Greening
- School of Rehabilitation Science, University of Saskatchewan, 104 Clinic Place, Saskatoon, SK S7N 0Z4, Canada.
| | - Nick Kmet
- School of Rehabilitation Science, University of Saskatchewan, 104 Clinic Place, Saskatoon, SK S7N 0Z4, Canada.
| | - Nadia Philipenko
- School of Rehabilitation Science, University of Saskatchewan, 104 Clinic Place, Saskatoon, SK S7N 0Z4, Canada.
| | - Lindsay Purves
- School of Rehabilitation Science, University of Saskatchewan, 104 Clinic Place, Saskatoon, SK S7N 0Z4, Canada.
| | - Jared Stevens
- School of Rehabilitation Science, University of Saskatchewan, 104 Clinic Place, Saskatoon, SK S7N 0Z4, Canada.
| | - Joel Lanovaz
- College of Kinesiology, University of Saskatchewan, Saskatoon, SK S7N 5B2, Canada.
| | - Scotty Butcher
- School of Rehabilitation Science, University of Saskatchewan, 104 Clinic Place, Saskatoon, SK S7N 0Z4, Canada.
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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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Dorrell HF, Moore JM, Smith MF, Gee TI. Validity and reliability of a linear positional transducer across commonly practised resistance training exercises. J Sports Sci 2018; 37:67-73. [PMID: 29851551 DOI: 10.1080/02640414.2018.1482588] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
Abstract
This study investigated the validity and reliability of the GymAware PowerTool (GPT). Thirteen resistance trained participants completed three visits, consisting of three repetitions of free-weight back squat, bench press, deadlift (80% one repetition maximum), and countermovement jump. Bar displacement, peak and mean velocity, peak and mean force, and jump height were calculated using the GPT, a three-dimensional motion capture system (Motion Analysis Corporation; 150 Hz), and a force plate (Kistler; 1500 Hz). Least products regression were used to compare agreeability between devices. A within-trial one-way ANOVA, typical error (TE; %), and smallest worthwhile change (SWC) were used to assess reliability. Regression analysis resulted in R2 values of >0.85 for all variables excluding deadlift mean velocity (R2 = 0.54-0.69). Significant differences were observed between visits 3-2 for bench press bar displacement (0.395 ± 0.055 m; 0.383 ± 0.053 m), and deadlift bar displacement (0.557 ± 0.034 m; 0.568 ± 0.034 m). No other significant differences were found. Low to moderate TE (0.6-8.8%) were found for all variables, with SWC ranging 1.7-7.4%. The data provides evidence that the GPT can be used to measure kinetic and kinematic outputs, however, care should be taken when monitoring deadlift performance.
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Affiliation(s)
- Harry F Dorrell
- a Human Performance Centre, School of Sport and Exercise Science, College of Social Sciences , University of Lincoln , Lincoln , UK
| | - Joseph M Moore
- a Human Performance Centre, School of Sport and Exercise Science, College of Social Sciences , University of Lincoln , Lincoln , UK
| | - Mark F Smith
- a Human Performance Centre, School of Sport and Exercise Science, College of Social Sciences , University of Lincoln , Lincoln , UK
| | - Thomas I Gee
- a Human Performance Centre, School of Sport and Exercise Science, College of Social Sciences , University of Lincoln , Lincoln , UK
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Lockie RG, Moreno MR, Lazar A, Risso FG, Liu TM, Stage AA, Birmingham-Babauta SA, Torne IA, Stokes JJ, Giuliano DV, Davis DL, Orjalo AJ, Callaghan SJ. The 1 Repetition Maximum Mechanics of a High-Handle Hexagonal Bar Deadlift Compared With a Conventional Deadlift as Measured by a Linear Position Transducer. J Strength Cond Res 2018; 32:150-161. [DOI: 10.1519/jsc.0000000000001781] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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15
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Cushion E, Howe L, Read P, Spence A. A Process for Error Correction for Strength and Conditioning Coaches. Strength Cond J 2017. [DOI: 10.1519/ssc.0000000000000338] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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16
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Hammer ME, Meir RA, Whitting JW, Crowley-McHattan ZJ. Shod vs. Barefoot Effects on Force and Power Development During a Conventional Deadlift. J Strength Cond Res 2017; 32:1525-1530. [PMID: 29016477 DOI: 10.1519/jsc.0000000000002246] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Hammer, ME, Meir, RA, Whitting, JW, and Crowley-McHattan, ZJ. Shod vs. barefoot effects on force and power development during a conventional deadlift. J Strength Cond Res 32(6): 1525-1530, 2018-The kinetics of a conventional deadlift in shod (S) vs. unshod (US) footwear conditions in 10 male participants (mean ± SD, age = 27.0 ± 5.8 years; body mass = 78.7 ± 11.5 kg; height = 175.8 ± 8.2 cm; 1 repetition maximum [1RM] deadlift = 155.8 ± 25.8 kg) was assessed in 2 testing sessions. A counterbalanced, cross-over experimental design was used with different loads (60 and 80% 1RM). Four sets of 4 repetitions were prescribed per session with 2 sets per shoe and with each shoe condition involving 1 set per load. Peak vertical force (PF), rate of force development (RFD), time to peak force (TPF), anterior-posterior (COP-AP) and mediolateral (COP-ML) center of pressure excursion, and barbell peak power data were recorded during all repetitions. Except for RFD (F = 6.389; p = 0.045; ηp = 0.516) and ML-COP (F = 6.696; p = 0.041; ηp = 0.527), there were no other significant main effects of shoe. There were significant main effects of load for PF (p ≤ 0.05), COP-AP (p = 0.011), TPF (p = 0.018), and COP-AP (p = 0.011). There were no significant interactions found between session, shoe, and load (p range from 0.944 to 0.086). Although the US condition may have produced changes in RFD and ML-COP compared with the shod condition, there is only limited evidence in the current study to support this lifting technique for the conventional deadlift. Further investigation is required to clarify any possible implications of this result and its benefit to lifters.
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Affiliation(s)
- Mark E Hammer
- School of Health and Human Sciences, Southern Cross University, Lismore, New South Wales, Australia
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Lockie RG, Lazar A. Exercise Technique: Applying the Hexagonal Bar to Strength and Power Training. Strength Cond J 2017. [DOI: 10.1519/ssc.0000000000000327] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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O'Reilly MA, Whelan DF, Ward TE, Delahunt E, Caulfield BM. Classification of deadlift biomechanics with wearable inertial measurement units. J Biomech 2017; 58:155-161. [PMID: 28545824 DOI: 10.1016/j.jbiomech.2017.04.028] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2016] [Revised: 04/25/2017] [Accepted: 04/30/2017] [Indexed: 11/19/2022]
Abstract
The deadlift is a compound full-body exercise that is fundamental in resistance training, rehabilitation programs and powerlifting competitions. Accurate quantification of deadlift biomechanics is important to reduce the risk of injury and ensure training and rehabilitation goals are achieved. This study sought to develop and evaluate deadlift exercise technique classification systems utilising Inertial Measurement Units (IMUs), recording at 51.2Hz, worn on the lumbar spine, both thighs and both shanks. It also sought to compare classification quality when these IMUs are worn in combination and in isolation. Two datasets of IMU deadlift data were collected. Eighty participants first completed deadlifts with acceptable technique and 5 distinct, deliberately induced deviations from acceptable form. Fifty-five members of this group also completed a fatiguing protocol (3-Repition Maximum test) to enable the collection of natural deadlift deviations. For both datasets, universal and personalised random-forests classifiers were developed and evaluated. Personalised classifiers outperformed universal classifiers in accuracy, sensitivity and specificity in the binary classification of acceptable or aberrant technique and in the multi-label classification of specific deadlift deviations. Whilst recent research has favoured universal classifiers due to the reduced overhead in setting them up for new system users, this work demonstrates that such techniques may not be appropriate for classifying deadlift technique due to the poor accuracy achieved. However, personalised classifiers perform very well in assessing deadlift technique, even when using data derived from a single lumbar-worn IMU to detect specific naturally occurring technique mistakes.
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Affiliation(s)
- Martin A O'Reilly
- Insight Centre for Data Analytics, University College Dublin, Ireland; School of Public Health, Physiotherapy and Sports Science, University College Dublin, Ireland.
| | - Darragh F Whelan
- Insight Centre for Data Analytics, University College Dublin, Ireland; School of Public Health, Physiotherapy and Sports Science, University College Dublin, Ireland
| | - Tomas E Ward
- Insight Centre for Data Analytics, Maynooth University, Ireland
| | - Eamonn Delahunt
- School of Public Health, Physiotherapy and Sports Science, University College Dublin, Ireland
| | - Brian M Caulfield
- Insight Centre for Data Analytics, University College Dublin, Ireland; School of Public Health, Physiotherapy and Sports Science, University College Dublin, Ireland
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Cochrane DJ, Barnes MJ. Muscle Activation and Onset Times of Hip Extensors during Various Loads of a Closed Kinetic Chain Exercise. Res Sports Med 2015; 23:179-89. [PMID: 25656945 DOI: 10.1080/15438627.2015.1005299] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
The aim of this study was to determine the muscle activity and onset time of hip extensors during a closed kinetic chain exercise (deadlift) at sub-maximal loads of 30%, 40%, 50%, and 75% of one repetition maximum (1RM). Twelve healthy males with at least three years of resistance training experience volunteered for the study. Biceps femoris (BF) and gluteus maximus (GM) muscle activity, onset time, peak and mean power were measured during the concentric phase of the deadlift. There was no main effect (p > 0.05) or no interaction effect for the onset time in BF and GM and for each load BF and GM had similar muscle activity. Increasing the external load during deadlift had no adverse effect on the relative onset time and it did not promote BF onset to occur before GM onset, thus both muscles were simultaneously activated, which should not compromise a delay in GM.
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Affiliation(s)
- Darryl J Cochrane
- a School of Sport and Exercise, Massey University , Palmerston North , New Zealand
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Nketiah G, Savio S, Dastidar P, Nikander R, Eskola H, Sievänen H. Detection of exercise load-associated differences in hip muscles by texture analysis. Scand J Med Sci Sports 2014; 25:428-34. [PMID: 24840507 DOI: 10.1111/sms.12247] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/09/2014] [Indexed: 12/15/2022]
Abstract
We examined whether specific physical exercise loading is associated with texture parameters from hip muscles scanned with magnetic resonance imaging (MRI). Ninety-one female athletes representing five distinct exercise-loading groups (high-impact, odd-impact, low-impact, nonimpact and high-magnitude) and 20 nonathletic female controls underwent MRI of the hip. Texture parameters were computed from the MRI images of four hip muscles (gluteus maximus, gluteus medius, iliopsoas and obturator internus). Differences in muscle texture between the athlete groups and the controls were evaluated using Mann-Whitney U-test. Significant (P < 0.05) textural differences were found between the high-impact (triple and high jumpers) and the control group in gluteus medius, iliopsoas and obturator internus muscles. Texture of the gluteus maximus, gluteus medius and obturator internus muscles differed significantly between the odd impact (soccer and squash players) and the control group. Textures of all studied muscles differed significantly between the low impact (endurance runners) and the controls. Only the gluteus medius muscle differed significantly between the nonimpact (swimmers) and the controls. No significant difference in muscle texture was found between the high-magnitude (powerlifters) and the control group. In conclusion, MRI texture analysis provides a quantitative method capable of detecting textural differences in hip muscles that are associated with specific types of long-term exercise loadings.
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Affiliation(s)
- G Nketiah
- Department of Electronics and Communications Engineering, Tampere University of Technology, Tampere, Finland
| | - S Savio
- Department of Electronics and Communications Engineering, Tampere University of Technology, Tampere, Finland.,Department of Radiology, Tampere University Hospital, Tampere, Finland
| | - P Dastidar
- Department of Radiology, Tampere University Hospital, Tampere, Finland
| | - R Nikander
- Department of Health Sciences, University of Jyväskylä, Jyväskylä, Finland.,GeroCenter Foundation for Aging Research and Development, Jyväskylä, Finland.,Jyväskylä Central Hospital, Jyväskylä, Finland
| | - H Eskola
- Department of Electronics and Communications Engineering, Tampere University of Technology, Tampere, Finland
| | - H Sievänen
- The UKK Institute for Health Promotion Research, Tampere, Finland
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Hales ME. Evaluating Common Weight Training Concepts Associated With Developing Muscular Strength: Truths or Myths? Strength Cond J 2011. [DOI: 10.1519/ssc.0b013e3181f453cc] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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