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Zehr JD, Davidson JM, Callaghan JP. Implementing an accelerometer-based pelvis segment for low back kinetic analyses during dynamic movement tasks. J Biomech 2024; 166:112060. [PMID: 38537369 DOI: 10.1016/j.jbiomech.2024.112060] [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: 11/03/2023] [Revised: 03/17/2024] [Accepted: 03/21/2024] [Indexed: 04/13/2024]
Abstract
An accelerometer-based pelvis has been employed to study segment and joint kinematics during scenarios involving close human-object interface and/or line-of-sight obstructions. However, its accuracy for examining low back kinetic outcomes is unknown. This study compared reaction moments and contact forces of the L5S1 joint calculated with an accelerometer-based and optically tracked pelvis segment. An approach to correct the global pelvis position as a function of thigh angle was developed. One participant performed four dynamic tasks: forward bend, squat, sit-to-stand-to-sit, and forward lunge. A standard bottom-up inverse dynamics approach was used and the root mean square error (RMSE) and coefficient of determination (R2) were calculated to examine kinetic differences between the optical and accelerometer approaches. The RMSE observed for L5S1 reaction flexion-extension moments ranged from 1.32 Nm to 2.20 Nm (R2 ≥ 0.98). The RMSE for net shear and compression reaction forces ranged from 2.13 to 10.45 N and 0.63 - 4.96 N, respectively. Similarly, the RMSE for L5S1 joint contact shear and compression ranged from 13.45 N to 19.51 N (R2 ≥ 0.85) and 31.18 N - 55.97 N (R2 ≥ 0.97), respectively. In conclusion, the accelerometer-based pelvis together with the approach to correct the global pelvis position is a feasible approach for computing low back kinetics with a single equivalent muscle model. The observed error in joint contact forces represents less than 5 % of the NIOSH recommended action limits and is unlikely to alter the interpretation of low back injury risk.
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Affiliation(s)
- Jackie D Zehr
- Human Performance Lab, University of Calgary, Calgary, Alberta, Canada
| | - Jessa M Davidson
- Department of Kinesiology & Health Sciences, University of Waterloo, Waterloo, Ontario, Canada
| | - Jack P Callaghan
- Department of Kinesiology & Health Sciences, University of Waterloo, Waterloo, Ontario, Canada.
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2
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Armstrong DP, Beach TAC, Fischer SL. Quantifying how functional and structural personal factors influence biomechanical exposures in paramedic lifting tasks. ERGONOMICS 2023:1-16. [PMID: 37830870 DOI: 10.1080/00140139.2023.2270728] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Accepted: 09/12/2023] [Indexed: 10/14/2023]
Abstract
It is unknown how structural (sex, stature, body mass) and functional (strength, flexibility) personal factors influence lifting strategy in paramedic work. We explored whether variance in peak low back forces and kinematic coordination patterns could be explained by structural and functional personal factors in paramedic lifting tasks. Seventy-two participants performed backboard and stretcher lifts. Peak low back forces normalised to body mass, as well as kinematic coordination patterns, were calculated as dependent variables. Being female, stronger, shorter, having higher body mass, and/or having greater lower body range of motion (ROM) were all independently associated with lower normalised low back forces across backboard and stretcher lifting. Females and stronger individuals seemed to define a movement objective to consistently minimise compressive forces, while individuals with greater hip ROM consistently minimised anteroposterior shear forces. The efficacy of improving strength and hip ROM to reduce low back forces in paramedic lifting should be investigated.Practitioner summary: Females, stronger individuals, and individuals with greater hip range of motion consistently exhibited lower normalised low back forces in paramedic lifting. Improving strength and hip range of motion via training is a potential proactive ergonomics approach to reduce peak low back forces in paramedic lifting tasks.
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Affiliation(s)
- Daniel P Armstrong
- Department of Kinesiology, Faculty of Health Sciences, University of Waterloo, Waterloo, Canada
| | - Tyson A C Beach
- Department of Kinesiology, Faculty of Health Sciences, University of Waterloo, Waterloo, Canada
| | - Steven L Fischer
- Department of Kinesiology, Faculty of Health Sciences, University of Waterloo, Waterloo, Canada
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3
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Dehaghani MR, Nourani A, Arjmand N. Effects of auxetic shoe on lumbar spine kinematics and kinetics during gait and drop vertical jump by a combined in vivo and modeling investigation. Sci Rep 2022; 12:18326. [PMID: 36316350 PMCID: PMC9622817 DOI: 10.1038/s41598-022-21540-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Accepted: 09/28/2022] [Indexed: 11/06/2022] Open
Abstract
The present study examined the effects of auxetic shoes on the biomechanics of the spine, as compared to barefoot and conventional shoe conditions, during gait and drop vertical jump (DVJ) activities using a combined in vivo and musculoskeletal modeling approach. Motion and force-plate data as well as electromyographic (EMG) activities of select trunk muscles of 11 individuals were collected during foregoing activities. In DVJ activity, two main phases of first landing (FL) and second landing (SL) were studied. In the FL phase of DVJ noticeable alternations were observed when auxetic shoes were used. That is, compared to the conventional footwear condition, smaller EMG activities in extensor muscles (by ~ 16-29%, p < 0.001), smaller anterior-posterior (AP) distance between the center of pressure of ground reaction force and heel (by ~ 19%, p = 0.002), generally larger maximal hip, knee, and ankle flexion angles (p < 0.005) and finally smaller maximal L5-S1 compression force and maximal external moment (by ~ 12 and 8%, respectively, p < 0.001) were obtained by wearing auxetic shoes. Our results, therefore, indicate that using auxetic shoes can reduce load on the lumbar spine during high-demanding activities such as vertical jump and thus may decrease the musculoskeletal risk of injuries during these activities.
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Affiliation(s)
- M. Rahmani Dehaghani
- grid.412553.40000 0001 0740 9747Department of Mechanical Engineering, Sharif University of Technology, Tehran, 11155-9567 Iran
| | - Amir Nourani
- grid.412553.40000 0001 0740 9747Department of Mechanical Engineering, Sharif University of Technology, Tehran, 11155-9567 Iran
| | - N. Arjmand
- grid.412553.40000 0001 0740 9747Department of Mechanical Engineering, Sharif University of Technology, Tehran, 11155-9567 Iran
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Effect of Heel Lift Insoles on Lower Extremity Muscle Activation and Joint Work during Barbell Squats. Bioengineering (Basel) 2022; 9:bioengineering9070301. [PMID: 35877352 PMCID: PMC9312299 DOI: 10.3390/bioengineering9070301] [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: 05/31/2022] [Revised: 07/05/2022] [Accepted: 07/05/2022] [Indexed: 11/17/2022] Open
Abstract
The effect of heel elevation on the barbell squat remains controversial, and further exploration of muscle activity might help find additional evidence. Therefore, 20 healthy adult participants (10 males and 10 females) were recruited for this study to analyze the effects of heel height on lower extremity kinematics, kinetics, and muscle activity using the OpenSim individualized musculoskeletal model. One-way repeated measures ANOVA was used for statistical analysis. The results showed that when the heel was raised, the participant’s ankle dorsiflexion angle significantly decreased, and the percentage of ankle work was increased (p < 0.05). In addition, there was a significant increase in activation of the vastus lateralis, biceps femoris, and gastrocnemius muscles and a decrease in muscle activation of the anterior tibialis muscle (p < 0.05). An increase in knee moments and work done and a reduction in hip work were observed in male subjects (p < 0.05). In conclusion, heel raises affect lower extremity kinematics and kinetics during the barbell squat and alter the distribution of muscle activation and biomechanical loading of the joints in the lower extremity of participants to some extent, and there were gender differences in the results.
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5
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Chan CK, Azah HN, Yeow CH, Goh SK, Ting HN, Salmah K. Effects of Squatting Speed and Depth on Lower Extremity Kinematics, Kinetics and Energetics. J MECH MED BIOL 2022. [DOI: 10.1142/s0219519422500324] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Squatting has received considerable attention in sports and is commonly utilized in daily activities. Knowledge of the squatting biomechanics in terms of its speed and depth may enhance exercise selection when targeting for sport-specific performance improvement and injury avoidance. Nonetheless, these perspectives have not been consistently reported. Hence, this preliminary study intends to quantify the kinematics, kinetics, and energetics in squat with different depths and speeds among healthy young adults with different physical activity levels; i.e., between active and sedentary groups. Twenty participants were administered to squat at varying depths (deep, normal, and half) and speeds (fast, normal, and slow). Motion-capture system and force plates were employed to acquire motion trajectories and ground reaction force. Joint moment was obtained via inverse dynamics, while power was derived as a product of moment and angular velocity. Higher speeds and deeper squats greatly influence higher joint moments and powers at the hip ([Formula: see text]) and knee ([Formula: see text]) than ankle, signifying these joints as the prime movers with knee as the predominant contributor. These preliminary findings show that the knee-strategy and hip-strategy were employed in compensating speed and depth manipulations during squatting. In certain contexts, appreciating these findings may provide clinically relevant implications, from the performance and injury avoidance viewpoint, which will ameliorate the physical activity level of practitioners.
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Affiliation(s)
- Chow-Khuen Chan
- Department of Biomedical Engineering, Universiti Malaya, Kuala Lumpur, Malaysia
- Department of Biomedical Engineering, National University of Singapore, Singapore
| | - Hamzaid Nur Azah
- Department of Biomedical Engineering, Universiti Malaya, Kuala Lumpur, Malaysia
| | - Chen-Hua Yeow
- Department of Biomedical Engineering, National University of Singapore, Singapore
| | - Sim-Kuan Goh
- Department of Mechanical Engineering, Nanyang Technological University, Singapore
| | - Hua-Nong Ting
- Department of Biomedical Engineering, Universiti Malaya, Kuala Lumpur, Malaysia
| | - Karman Salmah
- Department of Biomedical Engineering, Universiti Malaya, Kuala Lumpur, Malaysia
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Rolli F, Vitale JA, Pugliese L, Boccia G, LA Torre A, Pollitt L. The impact of foot angle on lower limb muscles activity during the back squat and counter movement jump. J Sports Med Phys Fitness 2021; 62:890-897. [PMID: 34498821 DOI: 10.23736/s0022-4707.21.12588-5] [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
BACKGROUND Squatting is a core exercise for many purposes. However, there is still controversy surrounding the practice of targeting specific muscle groups when performing the back squat with different stance widths or foot positions. Therefore, this study aimed to assess lower limb muscle activation during different form of back squat when adopting three different foot angles. METHODS Eight male active participants (age 24.0±0.8 years, height 1.80±0.63m and mass 85.8±8.7kg) performed maximal isometric squat, back squat with an overalod of 80% of 1 repetition maximum, and countermovement jump (CMJ) when adopting three foot rotation angles: parallel (0°); +10° outward (external rotation); +20° outward (external rotation). We calculated the root mean square of the electromyographic signals recorded from eight participant's dominant leg muscles. RESULTS During the descending phase of the back squat, the 20° external foot rotation elicited greater activation of the biceps femoris (+35%; p = 0.027) and gastrocnemius medialis (+70%; p = 0.040) compared to parallel foot. There were no significant differences among the other muscles and exercise conditions. CONCLUSIONS The +20° foot position increased BF and GasM muscle activity only during the downward phase of the back squat. Strength coaches should consider the present findings when selecting specific resistance exercises aiming to improve athletes' strength and physical fitness.
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Affiliation(s)
- Francesco Rolli
- Carnegie School of Sport, Leeds Beckett University, Leeds, UK.,Department of Biomedical Sciences for Health, Università degli Studi di Milano, Milano, Italy
| | - Jacopo A Vitale
- Laboratory of Movement and Sport Science, IRCCS Istituto Ortopedico Galeazzi, LaMSS, Milano, Italy -
| | - Lorenzo Pugliese
- Department of Biomedical Sciences for Health, Università degli Studi di Milano, Milano, Italy
| | - Gennaro Boccia
- Department of Clinical and Biological Sciences, University of Turin, Turin, Italy
| | - Antonio LA Torre
- Department of Biomedical Sciences for Health, Università degli Studi di Milano, Milano, Italy.,Laboratory of Movement and Sport Science, IRCCS Istituto Ortopedico Galeazzi, LaMSS, Milano, Italy
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7
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Pangan AM, Leineweber M. Footwear and Elevated Heel Influence on Barbell Back Squat: A Review. J Biomech Eng 2021; 143:1107012. [PMID: 33844006 DOI: 10.1115/1.4050820] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Indexed: 11/08/2022]
Abstract
The back squat is one of the most effective exercises in strengthening the muscles of the lower extremity. Understanding the impact of footwear has on the biomechanics is imperative for maximizing the exercise training potential, preventing injury, and rehabilitating from injury. This review focuses on how different types of footwear affect the full-body kinematics, joint loads, muscle activity, and ground reaction forces in athletes of varying experience performing the weighted back squat. The literature search was conducted using three databases, and fourteen full-text articles were ultimately included in the review. The majority of these studies demonstrated that the choice of footwear directly impacts kinematics and kinetics. Weightlifting shoes were shown to decrease trunk lean and generate more plantarflexion relative to running shoes and barefoot lifting. Elevating the heel through the use of external squat wedges is popular method during rehabilitation and was shown to provide similar effects to weightlifting shoes. Additional research with a broader array of populations, particularly novice and female weightlifters, should be conducted to generalize the research results to nonathlete populations. Further work is also needed to characterize the specific effects of sole stiffness and heel elevation height on squatting mechanics.
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Affiliation(s)
- Aaron Michael Pangan
- Biomedical Engineering Department, San José State University, One Washington Square, San Jose, CA 95192-0278
| | - Matthew Leineweber
- Biomedical Engineering Department, San José State University, One Washington Square, San Jose, CA 95192-0278
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8
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Kanwar KD, Cannon J, Nichols DL, Salem GJ, Mann MD. Injury risk-factor differences between two golf swing styles: a biomechanical analysis of the lumbar spine, hip and knee. Sports Biomech 2021:1-22. [PMID: 34280079 DOI: 10.1080/14763141.2021.1945672] [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: 10/28/2020] [Accepted: 06/14/2021] [Indexed: 10/20/2022]
Abstract
The golf swing has been associated with mechanical injury risk factors at many joints. One swing, the Minimalist Golf Swing, was hypothesised to reduce lumbar spine, lead hip, and lead knee ranges of motion and peak net joint moments, while affecting swing performance, compared to golfers' existing swings. Existing and MGS swings of 15 golfers with handicaps ranging from +2 to -20 were compared. During MGS downswing, golfers had 18.3% less lumbar spine transverse plane ROM, 40.7 and 41.8% less lead hip sagittal and frontal plane ROM, and 39.2% less lead knee sagittal plane ROM. MGS reduced lead hip extensor, abductor, and internal rotator moments by 17.8, 19.7 and 43%, while lead knee extensor, abductor, adductor and external rotator moments were reduced by 24.1, 26.6, 37 and 68.8% respectively. With MGS, club approach was 2° shallower, path 4° more in-to-out and speed 2 m/s slower. MGS reduced certain joint ROM and moments that are linked to injury risk factors, while influencing club impact factors with varying effect. Most golf injuries are from overuse, so reduced loads per cycle with MGS may extend the healthy life of joints, and permit golfers to play injury-free for more years.
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Affiliation(s)
- Kiran D Kanwar
- Department of Kinesiology, Texas Woman's University, Denton, TX, USA
- Golf Department, Stanton University, Garden Grove, CA, USA
| | - Jordan Cannon
- Musculoskeletal Biomechanics Research Laboratory, Division of Biokinesiology and Physical Therapy, University of Southern California, Los Angeles, CA, USA
| | - David L Nichols
- Department of Kinesiology, Texas Woman's University, Denton, TX, USA
| | - George J Salem
- Musculoskeletal Biomechanics Research Laboratory, Division of Biokinesiology and Physical Therapy, University of Southern California, Los Angeles, CA, USA
| | - Mark D Mann
- Department of Kinesiology, Texas Woman's University, Denton, TX, USA
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9
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Brice SM, Doma K, Spratford W. Effect of Footwear on the Biomechanics of Loaded Back Squats to Volitional Exhaustion in Skilled Lifters. J Strength Cond Res 2021; 36:2676-2684. [PMID: 33927116 DOI: 10.1519/jsc.0000000000003986] [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 Brice, SM, Doma, K, and Spratford, W. Effect of footwear on the biomechanics of loaded back squats to volitional exhaustion in skilled lifters. J Strength Cond Res XX(X): 000-000, 2021-This study examined whether footwear influences the movement dynamics of barbell back squats to volitional exhaustion in experienced lifters. Eleven men (1 repetition maximum [1RM] = 138 ± 19 kg; 1RM % body mass = 168 ± 18%) performed 3 sets (5-12 ± 4 repetitions per set) of loaded barbell back squats to volitional exhaustion using raised-heel and flat-heel footwear. Barbell motion as well as moments, angles, angular velocity, and power in the sagittal plane at the ankle, knee, hip, and lumbopelvis were examined during the second repetition of the first set (Tsecond) and the final repetition of the third set (Tfinal). There were significant reductions (p < 0.05) in lower-limb concentric angular velocity and power output for both footwear conditions. For the raised-heel condition at Tfinal, hip and knee concentric angular velocities were significantly slower (p < 0.05), and knee concentric power output was significantly less (p < 0.05) compared with the flat-heel condition. A reduction in barbell velocity was not observed for the raised-heel condition despite there being reduction in hip and knee angular velocities. Furthermore, no differences were identified in lower-limb joint moments or any of the biomechanical characteristics of the lumbopelvis between the footwear conditions. The findings of this study suggest that neither type of footwear reduced joint loading or improved joint range-of-motion.
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Affiliation(s)
- Sara M Brice
- Physical Sciences, College of Science and Engineering, James Cook University, Townsville, Australia; Sport and Exercise Science, College of Healthcare Sciences, James Cook University, Townsville, Australia; and Unversity of Canberra Research Institute of Sport and Exercise Science (UCRISE), University of Canberra, Canberra, Australia
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10
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Brazil A, Needham L, Palmer JL, Bezodis IN. A comprehensive biomechanical analysis of the barbell hip thrust. PLoS One 2021; 16:e0249307. [PMID: 33780488 PMCID: PMC8006986 DOI: 10.1371/journal.pone.0249307] [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] [Received: 09/02/2020] [Accepted: 03/16/2021] [Indexed: 11/18/2022] Open
Abstract
Barbell hip thrust exercises have risen in popularity within the biomechanics and strength and conditioning literature over recent years, as a method of developing the hip extensor musculature. Biomechanical analysis of the hip thrust beyond electromyography is yet to be conducted. The aim of this study was therefore to perform the first comprehensive biomechanical analysis the barbell hip thrust. Nineteen resistance trained males performed three repetitions of the barbell hip thrust at 70% one-repetition maximum. Kinematic (250 Hz) and kinetic (1000 Hz) data were used to calculate angle, angular velocity, moment and power data at the ankle, knee, hip and pelvic-trunk joint during the lifting phase. Results highlighted that the hip thrust elicits significantly (p < 0.05) greater bilateral extensor demand at the hip joint in comparison with the knee and pelvic-trunk joints, whilst ankle joint kinetics were found to be negligible. Against contemporary belief, hip extensor moments were not found to be consistent throughout the repetition and instead diminished throughout the lifting phase. The current study provides unique insight to joint kinematics and kinetics of the barbell hip thrust, based on a novel approach, that offers a robust evidence base for practitioners to guide exercise selection.
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Affiliation(s)
- Adam Brazil
- Department for Health, University of Bath, Bath, United Kingdom
| | - Laurie Needham
- Department for Health, University of Bath, Bath, United Kingdom
| | - Jac L Palmer
- Cardiff School of Sport and Health Sciences, Cardiff Metropolitan University, Cardiff, United Kingdom
| | - Ian N Bezodis
- Cardiff School of Sport and Health Sciences, Cardiff Metropolitan University, Cardiff, United Kingdom
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11
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Shiotani M, Hiyama T, Sato Y, Ozawa J, Kobayashi Y. Estimation model for lower extremity strength using gait movement measured with inertial sensor considering differences of sex and environment. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2020; 2020:3921-3926. [PMID: 33018858 DOI: 10.1109/embc44109.2020.9176384] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
In this study, we propose a method for estimating lower extremity strength from daily gait movement. Gait movement is affected by sex and gait environment. Therefore, we examined correlation coefficient between lower extremity strength and gait movement based on sex and environment and created models for estimating lower extremity strength. As a result, when only male or female data were used for model constructing, the correlation coefficient between estimates and actual measurements of lower extremity strength were approximately 0.7 and the precision had a mean absolute error of approximately 0.1 N/kg. The accuracy of the estimates was higher than that when sex was considered.
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12
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Sayers MGL, Hosseini Nasab SH, Bachem C, Taylor WR, List R, Lorenzetti S. The effect of increasing heel height on lower limb symmetry during the back squat in trained and novice lifters. BMC Sports Sci Med Rehabil 2020; 12:42. [PMID: 32728445 PMCID: PMC7382835 DOI: 10.1186/s13102-020-00191-y] [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: 12/10/2019] [Accepted: 07/20/2020] [Indexed: 11/10/2022]
Abstract
Background Symmetry during lifting is considered critical for allowing balanced power production and avoidance of injury. This investigation assessed the influence of elevating the heels on bilateral lower limb symmetry during loaded (50% of body weight) high-bar back squats. Methods Ten novice (mass 67.6 ± 12.4 kg, height 1.73 ± 0.10 m) and ten regular weight trainers (mass 66.0 ± 10.7 kg, height 1.71 ± 0.09 m) were assessed while standing on both the flat level floor and on an inclined board. Data collection used infra-red motion capture procedures and two force platforms to record bilateral vertical ground reaction force (GRFvert) and ankle, knee and hip joint kinematic and kinetic data. Paired t-tests and statistical parametric mapping (SPM1D) procedures were used to assess differences in discrete and continuous bilateral symmetry data across conditions. Results Although discrete joint kinematic and joint moment symmetry data were largely unaffected by raising the heels, the regular weight trainers presented greater bilateral asymmetry in these data than the novices. The one significant finding in these discrete data showed that raising the heels significantly reduced maximum knee extension moment asymmetry (P = 0.02), but in the novice group only. Time-series analyses indicated significant bilateral asymmetries in both GRFvert and knee extension moments mid-way though the eccentric phase for the novice group, with the latter unaffected by heel lift condition. There were no significant bilateral asymmetries in time series data within the regular weight training group. Conclusions This investigation highlights that although a degree of bilateral lower limb asymmetry is common in individuals performing back squats, the degree of this symmetry is largely unaffected by raising the heels. Differences in results for discrete and time-series symmetry analyses also highlight a key issue associated with relying solely on discrete data techniques to assess bilateral symmetry during tasks such as the back squat.
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Affiliation(s)
- Mark G L Sayers
- School of Health and Sport Sciences, University of the Sunshine Coast, Queensland, Australia
| | | | | | | | - Renate List
- Institute for Biomechanics, ETH Zürich, Zürich, Switzerland.,Human Performance Lab, Schulthess Clinic, Zürich, Switzerland
| | - Silvio Lorenzetti
- Institute for Biomechanics, ETH Zürich, Zürich, Switzerland.,Swiss Federal Institute of Sport, Magglingen, Switzerland
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13
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Sjöberg M, Berg HE, Norrbrand L, Andersen MS, Gutierrez-Farewik EM, Sundblad P, Eiken O. Influence of gravity on biomechanics in flywheel squat and leg press. Sports Biomech 2020; 22:767-783. [PMID: 32500840 DOI: 10.1080/14763141.2020.1761993] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Resistance exercise on Earth commonly involves both body weight and external load. When developing exercise routines and devices for use in space, the absence of body weight is not always adequately considered. This study compared musculoskeletal load distribution during two flywheel resistance knee-extension exercises, performed in the direction of (vertical squat; S) or perpendicular to (horizontal leg press; LP) the gravity vector. Eleven participants performed these two exercises at a given submaximal load. Motion analysis and musculoskeletal modelling were used to compute joint loads and to simulate a weightless situation. The flywheel load was more than twice as high in LP as in S (p < 0.001). Joint moments and forces were greater during LP than during S in the ankle, hip and lower back (p < 0.01) but were similar in the knee. In the simulated weightless situation, hip and lower-back loadings in S were higher than corresponding values at Earth gravity (p ≤ 0.01), whereas LP joint loads did not increase. The results suggest that LP is a better terrestrial analogue than S for knee-extension exercise in weightlessness and that the magnitude and direction of gravity during resistance exercise should be considered when designing and evaluating countermeasure exercise routines and devices for space.
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Affiliation(s)
- Maria Sjöberg
- Division of Environmental Physiology, Swedish Aerospace Physiology Centre, School of Engineering Sciences in Chemistry, Biotechnology, and Health (CBH), KTH Royal Institute of Technology, Solna, Sweden
| | - Hans E. Berg
- Department of Orthopaedic Surgery, Division for Orthopedics and Biotechnology, CLINTEC, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden
| | - Lena Norrbrand
- Division of Environmental Physiology, Swedish Aerospace Physiology Centre, School of Engineering Sciences in Chemistry, Biotechnology, and Health (CBH), KTH Royal Institute of Technology, Solna, Sweden
| | - Michael S. Andersen
- Department of Materials and Production, Aalborg University, Aalborg, Denmark
| | | | - Patrik Sundblad
- Division of Clinical Physiology, Department of Laboratory Medicine, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden
| | - Ola Eiken
- Division of Environmental Physiology, Swedish Aerospace Physiology Centre, School of Engineering Sciences in Chemistry, Biotechnology, and Health (CBH), KTH Royal Institute of Technology, Solna, Sweden
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14
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Sayers MGL, Bachem C, Schütz P, Taylor WR, List R, Lorenzetti S, Nasab SHH. The effect of elevating the heels on spinal kinematics and kinetics during the back squat in trained and novice weight trainers. J Sports Sci 2020; 38:1000-1008. [PMID: 32183616 DOI: 10.1080/02640414.2020.1738675] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
This research assessed the influence of various heel elevation conditions on spinal kinematic and kinetic data during loaded (25% and 50% of body weight) high-bar back squats. Ten novice (mass 67.6 ± 12.4 kg, height 1.73 ± 0.10 m) and ten regular weight trainers (mass 66.0 ± 10.7 kg, height 1.71 ± 0.09 m) completed eight repetitions at each load wearing conventional training shoes standing on the flat level floor (LF) and on an inclined board (EH). The regular weight training group performed an additional eight repetitions wearing weightlifting shoes (WS). Statistical parametric mapping (SPM1D) and repeated measures analysis of variance were used to assess differences in spinal curvature and kinetics across the shoe/floor conditions and loads. SPM1D analyses indicated that during the LF condition the novice weight trainers had greater moments around L4/L5 than the regular weight trainers during the last 20% of the lift (P < 0.05), with this difference becoming non-significant during the EH condition. This study indicates that from a perspective of spinal safety, it appears advantageous for novice weight trainers to perform back squats with their heels slightly elevated, while regular weight trainers appear to realize only limited benefits performing back squats with either EH or WS.
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Affiliation(s)
- Mark G L Sayers
- School of Health and Sport Sciences, University of the Sunshine Coast, Maroochydore DC, Australia
| | | | - Pascal Schütz
- ETH, Institute for Biomechanics, Zürich, Switzerland
| | | | - Renate List
- ETH, Institute for Biomechanics, Zürich, Switzerland.,Human Performance Lab, Schulthess Clinic, Zürich, Switzerland
| | - Silvio Lorenzetti
- ETH, Institute for Biomechanics, Zürich, Switzerland.,Swiss Federal Institute of Sport, Magglingen, Switzerland
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15
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Brice SM, Doma K, Harland L, Spratford W. Impact of performing heavy-loaded barbell back squats to volitional failure on lower limb and lumbo-pelvis mechanics in skilled lifters. J Sports Sci 2019; 38:100-105. [PMID: 31638481 DOI: 10.1080/02640414.2019.1683385] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
A common practice in resistance training is to perform sets of exercises at, or close to failure, which can alter movement dynamics. This study examined ankle, knee, hip, and lumbo-pelvis dynamics during the barbell back squat under a moderate-heavy load (80% of 1 repetition maximum (1RM)) when performed to failure. Eleven resistance trained males performed three sets to volitional failure. Sagittal plane movement dynamics at the ankle, knee, hip, and lumbo-pelvis were examined; specifically, joint moments, joint angles, joint angular velocity, and joint power. The second repetition of the first set and the final repetition of the third set were compared. Results showed that while the joint movements slowed (p < 0.05), the joint ranges of motion were not altered There were significant changes in most mean joint moments (p < 0.05), indicating altered joint loading. The knee moment decreased while the hip and lumbo-pelvis moments underwent compensatory increases. At the knee and hip, there were significant decreases (p < 0.05) in concentric power output (p < 0.05). Whilst performing multiple sets to failure altered some joint kinetics, the comparable findings in joint range ofmotion suggest that technique was not altered. Therefore, skilled individuals appear to maintain technique when performing to failure.
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Affiliation(s)
- Sara M Brice
- Physical Sciences, College of Science and Engineering, James Cook University, Townsville, Australia
| | - Kenji Doma
- Sport and Exercise Science, College of Healthcare Sciences, James Cook University, Townsville, Australia
| | - Liam Harland
- Sport and Exercise Science, College of Healthcare Sciences, James Cook University, Townsville, Australia
| | - Wayne Spratford
- Research Institute of Sport and Exercise Science, University of Canberra, Canberra, Australia
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16
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Zehr JD, Howarth SJ, Beach TA. Using relative phase analyses and vector coding to quantify Pelvis-Thorax coordination during lifting—A methodological investigation. J Electromyogr Kinesiol 2018; 39:104-113. [DOI: 10.1016/j.jelekin.2018.02.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2017] [Revised: 12/30/2017] [Accepted: 02/11/2018] [Indexed: 10/18/2022] Open
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17
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Zehr JD, Carnegie DR, Welsh TN, Beach TAC. A comparative analysis of lumbar spine mechanics during barbell- and crate-lifting: implications for occupational lifting task assessments. INTERNATIONAL JOURNAL OF OCCUPATIONAL SAFETY AND ERGONOMICS 2018; 26:1-8. [DOI: 10.1080/10803548.2018.1439872] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- Jackie D. Zehr
- Department of Kinesiology, University of Waterloo, Canada
| | | | - Timothy N. Welsh
- Faculty of Kinesiology and Physical Education, University of Toronto, Canada
| | - Tyson A. C. Beach
- Faculty of Kinesiology and Physical Education, University of Toronto, Canada
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