Journal of biomechanics最新文献_第7页

Three-dimensional hip and knee loading during the Copenhagen adductor exercise 哥本哈根内收肌运动中的三维髋关节和膝关节负荷。

IF 2.4 3区医学 Q3 BIOPHYSICS

Journal of biomechanics

Pub Date : 2025-12-08 DOI: 10.1016/j.jbiomech.2025.113116

Torstein E. Dæhlin , Daryna Dmytriieva , Emma Rutherford , Loren Z.F. Chiu

The Copenhagen adductor exercise (CAE) is used for groin muscle strengthening. While these muscles primarily act in the frontal plane, the hip adductor muscles may also act in the sagittal and transverse planes. Therefore, the CAE likely imposes three-dimensional (3D) muscular demands at both the hip and knee. This study aimed to quantify the 3D hip and knee joint loading during variations of the CAE. Eleven men and 13 women performed the exercise with the support stand at the knee, ankle, and midway between the knee and ankle. Ground reaction forces under the stand and reflective markers trajectories were recorded to calculate hip and knee net joint moments (NJM). Hip adductor NJM was largest for the ankle support (1.54 ± 0.23 Nm·kg⁻¹) and smallest for the knee support (0.93 ± 0.16 Nm·kg⁻¹; P < 0.001). Most participants had a hip extensor NJM, that was also greater for more distal support locations (Δ_ankle-mid = −0.10 ± 0.21 Nm·kg⁻¹; Δ_ankle-knee = −0.20 ± 0.27 Nm·kg⁻¹; P < 0.001). Support locations distal to the knee had knee adductor and flexor NJM. The hip and knee sagittal plane NJMs were strongly correlated with transverse plane thigh (r = 0.97–0.98, P < 0.017) and shank (r = 0.89–0.93, P < 0.017) orientations, respectively. Medial thigh rotation was associated with a hip flexor NJM while lateral thigh rotation was associated with a hip extensor NJM. CAE requires frontal and sagittal plane muscle efforts at the hip and knee, which are greater for more distal support locations.

哥本哈根内收肌运动（CAE）用于腹股沟肌肉的强化。虽然这些肌肉主要作用于额平面，但髋内收肌也可能作用于矢状面和横平面。因此，CAE可能会对髋关节和膝关节施加三维（3D）肌肉需求。本研究旨在量化CAE变化期间髋关节和膝关节的三维负荷。11名男性和13名女性在膝盖、脚踝以及膝盖和脚踝之间的中间位置放置支撑架。记录支架下的地面反作用力和反射标记物轨迹，计算髋关节和膝关节关节力矩（NJM）。髋关节内收肌NJM对踝关节支撑作用最大（1.54±0.23 Nm·kg-1），对膝关节支撑作用最小（0.93±0.16 Nm·kg-1, P < 0.001）。大多数参与者都有髋关节伸肌NJM，在更远的支持位置也更大（Δankle-mid = -0.10±0.21 Nm·kg-1； Δankle-knee = -0.20±0.27 Nm·kg-1; P < 0.001）。膝关节远端支撑部位有膝内收肌和屈肌NJM。髋、膝矢状面NJMs分别与横切面大腿方向（r = 0.97-0.98, P < 0.017）和小腿方向（r = 0.89-0.93, P < 0.017）密切相关。大腿内侧旋转与髋关节屈肌NJM有关，而大腿外侧旋转与髋关节伸肌NJM有关。CAE需要髋关节和膝关节的额位和矢状面肌肉力量，对于更远的支持位置，这是更大的。

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引用次数: 0

An artificial neural network to estimate detailed active–passive spinal loads during static lifting activities for a standardized anthropometry 一个人工神经网络，以估计详细的主动被动脊柱负荷在静态举重活动的标准化人体测量

IF 2.4 3区医学 Q3 BIOPHYSICS

Journal of biomechanics

Pub Date : 2025-12-08 DOI: 10.1016/j.jbiomech.2025.113115

Hassan Mohammadi, Navid Arjmand

Numerous musculoskeletal models have been developed to estimate spine loads for use in occupational risk assessment programs. These models typically oversimplify the complex intervertebral joints by representing them as pivots, thereby failing to estimate load sharing among the intervertebral discs, facet joints, ligaments and disc annulus/nucleus. Our coupled musculoskeletal-finite-element model integrates both the musculature and detailed geometry of the passive spine to yield comprehensive predictions for a standardized anthropometry. However, this model is time/skill-intensive. We aimed to train an artificial neural network (ANN) to replicate the outputs of this model during sagittally-symmetric static lifting tasks. A training dataset was generated by simulating 500 tasks using the model with different hand-loads (up to 20 kg) and positions (up to 30 cm horizontal distance from the shoulders), trunk flexions (up to 80°), and lumbopelvic ratios (3 levels for each flexion angle). The outputs included T12-S1 intradiscal pressure, maximum annulus principal stress, disc compressive/shear loads, resultant facet joint forces, resultant force of all posterior ligaments, and force in trunk muscles. The ANN successfully mapped the model inputs to its 83 outputs with satisfactory predictive accuracy; normalized-root-mean-squared-errors < 3 % and R² > 0.98. Bland-Altman analyses indicated no consistent bias between the ANN and model predictions, with a narrow 95 % limits of agreement across all outputs, e.g., 0.1 MPa for L4-L5 intradiscal pressure. This ANN is a fast practical tool for risk assessment applications. It can also be used to provide realistic trunk muscle-driven loading scenarios for passive finite element spine models in biomechanical evaluations.

许多肌肉骨骼模型已经开发估计脊柱负荷用于职业风险评估程序。这些模型通常通过将复杂的椎间关节表示为枢轴来过度简化它们，从而无法估计椎间盘、小关节、韧带和椎间盘环/核之间的负荷分担。我们的耦合肌肉-骨骼-有限元模型集成了被动脊柱的肌肉组织和详细几何形状，从而为标准化的人体测量学提供全面的预测。然而，这种模式是时间/技能密集型的。我们的目标是训练一个人工神经网络（ANN）来复制该模型在矢状对称静态提升任务中的输出。通过使用该模型模拟500个任务，生成训练数据集，这些任务具有不同的手负荷（高达20公斤）和位置（距离肩部高达30厘米的水平距离），躯干屈曲（高达80°）和腰骨盆比例（每个屈曲角度有3个级别）。输出包括T12-S1椎间盘内压力、最大环主应力、椎间盘压缩/剪切载荷、关节突关节合力、所有后韧带合力和躯干肌肉力。人工神经网络成功地将模型输入映射到它的83个输出，并具有令人满意的预测精度；标准化均方根误差<； 3%, R2 > 0.98。Bland-Altman分析表明，人工神经网络和模型预测之间没有一致的偏差，所有输出的一致性限制为95%，例如L4-L5椎间盘内压力为0.1 MPa。该人工神经网络是一种快速实用的风险评估工具。它也可以用于提供真实的躯干肌肉驱动的加载场景被动有限元脊柱模型在生物力学评估。

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引用次数: 0

Assessing sensitivity of predictive shoulder simulations to uncertain soft tissue properties 评估预测肩部模拟对不确定软组织特性的敏感性

IF 2.4 3区医学 Q3 BIOPHYSICS

Journal of biomechanics

Pub Date : 2025-12-08 DOI: 10.1016/j.jbiomech.2025.113114

Morgan J. Dalman, Katherine R. Saul

Accurate modeling of glenohumeral joint mechanics requires reliable representations of passive structures such as ligaments and articular cartilage, yet these tissue properties are un-available in vivo on a subject-specific basis. This study evaluated how variability in ligament and cartilage properties propagates to joint-level outcomes. Using a validated musculoskeletal shoulder model and two Monte Carlo simulation frameworks, we independently varied glenohumeral ligament (stiffness and slack length) and cartilage (elastic modulus and thickness) parameters to predict secondary kinematics and joint contact mechanics during scaption. Regression analysis revealed that ligament slack length, particularly for the anterior and middle glenohumeral ligaments (A-IGHL and MGHL), had the most significant influence across outcomes. Articular cartilage properties also contributed significantly to contact mechanics, reinforcing their role as key contributors to load distribution. These findings are especially relevant for modeling pathological conditions such as osteoarthritis and surgical intervention such as joint replacement and ligament reconstructions, where cartilage and ligament structure and properties are altered. This work underscores the importance of accounting for soft tissue variability in subject-specific shoulder simulations and highlights targets for advancing in vivo characterization methods.

盂肱关节力学的精确建模需要可靠的被动结构表征，如韧带和关节软骨，然而这些组织特性在个体体内是不可用的。本研究评估了韧带和软骨特性的可变性如何传播到关节水平的结果。使用一个经过验证的肌肉骨骼肩部模型和两个蒙特卡罗模拟框架，我们独立地改变肩关节韧带（刚度和松弛长度）和软骨（弹性模量和厚度）参数，以预测截肢过程中的二次运动学和关节接触力学。回归分析显示，韧带松弛长度，特别是前和中盂肱韧带（A-IGHL和MGHL），对所有结果的影响最为显著。关节软骨的特性也对接触力学有重要影响，加强了它们作为载荷分配的关键贡献者的作用。这些发现对于骨关节炎和手术干预（如关节置换术和韧带重建）等病理条件的建模尤其相关，其中软骨和韧带的结构和特性被改变。这项工作强调了在特定受试者肩部模拟中考虑软组织变异性的重要性，并强调了推进体内表征方法的目标。

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引用次数: 0

The effect of component offset on acromion and scapular spine strains following reverse total shoulder arthroplasty: An ex-vivo shoulder motion study 反向全肩关节置换术后构件偏移对肩峰和肩胛骨拉伤的影响：一项离体肩关节运动研究。

IF 2.4 3区医学 Q3 BIOPHYSICS

Journal of biomechanics

Pub Date : 2025-12-06 DOI: 10.1016/j.jbiomech.2025.113112

David T. Axford , Robert Potra , Richard Appleyard , Janos Tomka , Antonio Arenas-Miquelez , Desmond J. Bokor , Louis M. Ferreira , Sumit Raniga

The effects of component offset in reverse total shoulder arthroplasty (rTSA) on acromion and scapular spine strains are not well understood, and no comparison of strain patterns between the native and implanted shoulder exists. This study investigated the effects of humerus distalization, humerus lateralization, glenosphere lateralization, and humerus-to-glenosphere lateralization ratio in rTSA on acromion and scapular spine strains during simulated unconstrained shoulder motion and compared the observed strain patterns to the native condition. Seven cadaveric specimens were tested on a shoulder simulator which performed scapular plane abduction and internal-external rotation. Maximum principal strain was measured in four clinically relevant regions according to the Levy classification system using strain gauge rosettes. Overall, rTSA conditions had higher strains than the native condition at low elevation (p < 0.05) but not at high elevation. During scapular plane abduction, strain peaked at low elevation for all reverse conditions, but at high elevation angles in the native condition. Strain increased significantly with humerus distalization in Levy 3A (p = 0.038), while strain decreased significantly in all regions with humerus lateralization (p ≤ 0.049). Isolated glenosphere lateralization had no effect on scapula strains (p ≥ 0.162) while humerus-sided lateralization resulted in significantly less strain than combined humerus and glenosphere lateralization (p ≤ 0.015). RTSA alters the strain patterns on the acromion and scapular spine from those observed in the native shoulder. In addition, component offset had significant effects on scapula strains demonstrating that implant configuration likely has an influence on the occurrence of acromion and scapular spine fractures.

逆行全肩关节置换术（rTSA）中构件偏移对肩峰和肩胛骨应变的影响尚不清楚，也没有对原生肩关节和植入肩关节的应变模式进行比较。本研究研究了rTSA中肱骨远端化、肱骨侧化、关节盂侧化和肱骨-关节盂侧化比例对模拟无约束肩部运动中肩峰和肩胛骨应变的影响，并将观察到的应变模式与自然状态进行了比较。7具尸体标本在肩胛骨平面外展和内外旋转的肩部模拟器上进行了测试。最大主应变测量在四个临床相关区域根据列维分类系统使用应变计玫瑰花。总体而言，低海拔rTSA条件下的菌株数量高于自然条件(p

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引用次数: 0

Effects of vibration frequency, amplitude, and direction on human gait metrics 振动频率、振幅和方向对人体步态测量的影响

IF 2.4 3区医学 Q3 BIOPHYSICS

Journal of biomechanics

Pub Date : 2025-12-06 DOI: 10.1016/j.jbiomech.2025.113100

Flavia Marrone , Filippo Motta , Stefano Marelli , Manuela Galli , Marco Tarabini , Pierre Lemerle

The effect of vibrations on gait is a topic that has not been sufficiently analyzed. Thirty-one volunteers underwent 50 walking trials on a modified treadmill with three degrees of freedom including normal walking and walking in the presence of sinusoidal roll, pitch, and vertical vibration. A full factorial design of experiments was adopted, using two vibration amplitudes (4 or 8 cm for linear displacements, 4° or 8° for angular oscillations), four frequencies (0.25, 0.5, 0.7, and 1 Hz), and two walking speeds (0.7 or 1 m/s). A significant alteration of all the gait metrics was found in the presence of vibration, but the step width and cadence resulted in the most affected. A combined effect of all factors was found, with the major impact on gait in the case of rotational vibration, mainly in the case of roll, at higher amplitude and frequencies. Understanding the most detrimental vibration conditions contributes to updating the ISO standard for whole-body vibration considering exposed walking workers.

振动对步态的影响是一个尚未得到充分分析的话题。31名志愿者在改良的跑步机上进行了50次步行试验，试验有三个自由度，包括正常行走和在正弦滚动、俯仰和垂直振动的情况下行走。实验采用全因子设计，采用两种振动幅度（线性位移为4或8 cm，角振荡为4°或8°），四种频率（0.25、0.5、0.7和1 Hz）和两种行走速度（0.7或1 m/s）。在振动存在的情况下，所有步态指标都有显著的变化，但步宽和节奏受到的影响最大。发现了所有因素的综合影响，在旋转振动的情况下，主要是在滚动的情况下，在较高的振幅和频率下，对步态的影响最大。了解最有害的振动条件有助于更新考虑到暴露的步行工人的全身振动的ISO标准。

引用次数: 0

A distal-to-proximal shift is not a requisite mechanism for greater metabolic cost of walking in older adults 远端到近端移位并不是老年人行走代谢成本增加的必要机制

IF 2.4 3区医学 Q3 BIOPHYSICS

Journal of biomechanics

Pub Date : 2025-12-06 DOI: 10.1016/j.jbiomech.2025.113109

Jacob M. Thomas, Zoe H. Smith, Jane A. Kent, Katherine A. Boyer

A greater metabolic cost of walking (CoW) is well-documented in older compared with young adults and is likely a catalyst for age-related mobility loss. Proximal redistribution of joint work during gait has been suggested as a contributor to greater CoW in aging. However, evidence to support this link is limited. We collected overground gait kinematics and kinetics as well as metabolic data during a 7-minute treadmill walk (7MTW) in 15 young (30–40 years, 8F) and 40 older (70–80 years) adults. We then separated the older adults into two groups based on whether they did (O_R, n = 15 (5F)), or did not (O_NR, n = 25 (17F)), proximally redistribute joint work using a redistribution ratio (RR), where O_R had an RR > 0.79 (Young mean RR + 1 SD) and O_NR had an RR ≤ 0.79. Contrary to our hypothesis, CoW was not different between O_R (0.105 ± 0.019 ml·kg⁻¹·min⁻¹) and O_NR (0.106 ± 0.016 ml·kg⁻¹·min⁻¹), while moderate-to-large effects for CoW were observed for both O_NR (P = 0.035, d = 0.83) and O_R (P = 0.106, d = 0.70) when compared to young (0.089 ± 0.013 ml·kg⁻¹·min⁻¹). These results suggest that the distal-to-proximal shift does not explain the greater CoW in older adults and further that restoring a “youthful” gait pattern may not address the problem of a greater CoW in older adults. Group characteristics such as age or preferred walking speed did not differ between the O_R and O_NR, but O_R was comprised predominantly of male participants suggesting sex specific factors for the gait shift should be queried.

与年轻人相比，老年人行走的代谢成本（CoW）更高，这可能是与年龄相关的行动能力丧失的催化剂。步态过程中关节工作的近端再分配被认为是衰老过程中更大的CoW的一个因素。然而，支持这种联系的证据有限。我们收集了15名年轻人（30-40岁，8F）和40名老年人（70-80岁）在7分钟跑步机步行（7MTW）期间的地上步态运动学和动力学以及代谢数据。然后，我们根据老年人是否有（OR, n = 15 (5F)）或没有（ONR, n = 25 (17F)）将他们分为两组，使用再分配比（RR）对关节工作进行近端重新分配，其中OR的RR为0.79 (Young mean RR + 1 SD)，而ONR的RR≤0.79。与我们的假设相反，CoW在OR（0.105±0.019 ml·kg - 1·min - 1）和ONR（0.106±0.016 ml·kg - 1·min - 1）之间没有差异，而与年轻（0.089±0.013 ml·kg - 1·min - 1）相比，ONR （P = 0.035, d = 0.83）和OR （P = 0.106, d = 0.70）对CoW都有中等到较大的影响。这些结果表明，远端到近端移位并不能解释老年人更大的CoW，进一步说，恢复“年轻”的步态模式可能不能解决老年人更大的CoW的问题。组特征，如年龄或首选步行速度在or和ONR之间没有差异，但or主要由男性参与者组成，这表明步态变化的性别特定因素应该被询问。

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引用次数: 0

A novel pipeline using statistical parametric mapping for assessing differences in three- and four-dimensional computed tomography-derived arthrokinematics 一个新的管道使用统计参数映射来评估三维和四维计算机断层扫描衍生的关节运动学的差异

IF 2.4 3区医学 Q3 BIOPHYSICS

Journal of biomechanics

Pub Date : 2025-12-06 DOI: 10.1016/j.jbiomech.2025.113101

Taylor P. Trentadue , Andrew R. Thoreson , Thor E. Andreassen , Cesar Lopez , David R. Holmes III , Sanjeev Kakar , Shuai Leng , Kristin D. Zhao

Four-dimensional computed tomography (4DCT) can be used to quantify joint mechanics during dynamic tasks. Post-processing of 3D anatomical renderings permits calculation of joint surface arthrokinematics. Given the complexity and high dimensionality of arthrokinematic data, as well as variations in interparticipant morphology, sophisticated analytical techniques permitting comparisons between participants and throughout motion cycles are needed. Statistical parametric mapping (SPM) has been applied to biomechanical and imaging datasets to overcome this challenge; however, applications to 4DCT remain under-explored. The proposed pipeline is demonstrated at the distal radioulnar joint (DRUJ). This application explores relationships between wrist position (a continuous variable) and arthrokinematic interosseous proximities (a surface-based measure) in two contexts. Static-neutral CT data from 30 normative participants are used in the first application. Bilateral 4DCT pronosupination arcs from two participants with unilateral injury are included in the second application. A canonical joint was created using a multi-level, multi-object statistical shape model, on which the articular surface of interest was defined. Participant-specific joint surfaces were predicted from the canonical template via non-linear morphing. SPM regression and generalized linear models were used to explore relationships between wrist position, injury status, and interosseous proximities. The analysis captured position-related differences in interosseous proximities, demonstrating the application of this pipeline to 3DCT- and 4DCT-derived arthrokinematics. As hypothesized, increased pronation was associated with increased proximities at the sigmoid notch volar margin. The proposed pipeline can be applied to other joints, functional tasks, experimental conditions, or injury states to quantify how arthrokinematics are related to both continuous and categorical variables.

四维计算机断层扫描（4DCT）可用于量化动态任务中的关节力学。三维解剖效果图的后处理允许关节表面关节运动学的计算。考虑到关节运动学数据的复杂性和高维性，以及参与者之间形态的变化，需要复杂的分析技术来比较参与者之间和整个运动周期。统计参数映射（SPM）已应用于生物力学和成像数据集，以克服这一挑战；然而，4DCT的应用仍未得到充分探索。在远端尺桡关节（DRUJ）处展示了拟议的管道。本应用在两种情况下探讨了手腕位置（一个连续变量）和关节运动学骨间距离（一个基于表面的测量）之间的关系。在第一次应用中使用了来自30个规范参与者的静态中立CT数据。来自两名单侧损伤参与者的双侧4DCT旋前弧线包括在第二次应用中。利用多层次、多目标的统计形状模型创建典型关节，并在该模型上定义感兴趣的关节面。通过非线性变形从规范模板中预测参与者特定的关节面。SPM回归和广义线性模型用于探讨腕部位置、损伤状态和骨间距离之间的关系。该分析捕获了骨间邻近部位的位置相关差异，展示了该管道在3DCT和4dct衍生关节运动学中的应用。正如假设的那样，旋前增加与乙状突切迹掌侧缘近端增加有关。所提出的管道可以应用于其他关节、功能任务、实验条件或损伤状态，以量化关节运动学如何与连续变量和分类变量相关。

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引用次数: 0

Standing vs. side-lying and supine: a comparison of hip torque collection methodologies using the Biodex system 站立与侧卧和仰卧：使用Biodex系统的髋关节扭矩收集方法的比较

IF 2.4 3区医学 Q3 BIOPHYSICS

Journal of biomechanics

Pub Date : 2025-12-06 DOI: 10.1016/j.jbiomech.2025.113098

Mario E. Garcia , Quentin Shin , Emily McCain , Xiao Hu , Shawn Russell , Silvia S. Blemker

Maximum isometric joint torque can be used to evaluate muscle strength and tune computational models in biomechanics. However, variability in joint and body positioning complicates the interpretation of hip torque data. This study aimed to compare standing and side-lying/supine body positions during hip maximum voluntary isometric contractions across abduction, adduction, flexion, and extension. Subjects performed isometric hip torque trials using a Biodex dynamometer, with surface electromyography monitoring muscle activation in select hip muscles. Significant differences in normalized torque values were observed between standing and side-lying/supine positions, with standing producing higher torques in adduction and extension and side-lying favoring abduction. Muscle activation analyses revealed statistically significant biceps femoris activation during standing extension. Standardized protocols are essential for enhancing data consistency and advancing applications in biomechanics. The standing position’s functional relevance and consistent torque production for movements like extension suggest its suitability for clinical and research applications.

最大等距关节扭矩可用于评估肌肉力量和调整生物力学计算模型。然而，关节和身体位置的变化使髋部扭矩数据的解释复杂化。本研究旨在比较髋关节外展、内收、屈曲和伸展时最大自主等距收缩时的站立和侧卧/仰卧体位。受试者使用Biodex测力计进行等距髋关节扭矩试验，并使用表面肌电图监测选定髋关节肌肉的肌肉激活情况。在站立和侧卧/仰卧位之间观察到归一化扭矩值的显着差异，站立在内收和伸展时产生更高的扭矩，侧卧有利于外展。肌肉激活分析显示，在站立伸展期间，有统计学意义的股二头肌激活。标准化协议对于增强数据一致性和推进生物力学应用至关重要。站立姿势的功能相关性和一致的扭矩产生运动，如伸展，表明其适合临床和研究应用。

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引用次数: 0

Influence of carbon-plated running shoes and fatigue on lower limb biomechanics 镀碳跑鞋和疲劳对下肢生物力学的影响

IF 2.4 3区医学 Q3 BIOPHYSICS

Journal of biomechanics

Pub Date : 2025-12-05 DOI: 10.1016/j.jbiomech.2025.113102

Xiangdong Luo , Ruijiao Liu , Bo Li

This study aimed to investigate the effects of shoe longitudinal bending stiffness and fatigue state on lower limb joint biomechanics and impact loading characteristics during running. Sixteen participants were tested using a 3D motion capture system and force platforms to collect and analyze kinematic and kinetic data of the metatarsophalangeal, ankle, knee, and hip joints, as well as the average vertical loading rate (VALR) of ground reaction force, under two footwear conditions before and after induced running fatigue. Carbon-plated shoes significantly restricted metatarsophalangeal joint flexion, while hip transverse plane range of motion was notably affected by fatigue. Fatigue primarily reduced knee joint flexion–extension moment and stiffness, increased ankle pronation moment, and elevated VALR. A significant interaction effect between fatigue and shoe type was observed on VALR, with non-carbon shoes demonstrating superior shock attenuation under fatigue. Shoe structure and fatigue state significantly influence multi-joint coordination and control in the lower limbs. This study supports the “distal restriction–proximal compensation” mechanism, suggesting that while carbon-plated shoes enhance propulsion efficiency, the restricted distal mobility, especially under fatigue, increases compensatory loading and injury risk in proximal joints.

本研究旨在探讨跑鞋纵向弯曲刚度和疲劳状态对跑步时下肢关节生物力学和冲击载荷特性的影响。使用3D运动捕捉系统和受力平台对16名参与者进行测试，收集和分析在诱导跑步疲劳前后两种鞋类条件下跖趾、踝关节、膝关节和髋关节的运动学和动力学数据，以及地面反作用力的平均垂直加载率（VALR）。碳板鞋明显限制跖指关节屈曲，而髋横平面运动范围明显受疲劳影响。疲劳主要降低膝关节屈伸力矩和刚度，增加踝关节旋前力矩，升高VALR。疲劳与鞋型之间存在显著的交互作用，非碳鞋在疲劳条件下表现出更好的冲击衰减。鞋的结构和疲劳状态对下肢多关节的协调和控制有显著影响。该研究支持“远端限制-近端补偿”机制，表明虽然碳涂层鞋提高了推进效率，但远端受限的活动能力，特别是在疲劳情况下，增加了近端关节的代偿负荷和损伤风险。

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引用次数: 0

Biomechanical and neuromuscular differences between the snatch and clean in elite weightlifters 优秀举重运动员抓举和挺举的生物力学和神经肌肉差异

IF 2.4 3区医学 Q3 BIOPHYSICS

Journal of biomechanics

Pub Date : 2025-12-05 DOI: 10.1016/j.jbiomech.2025.113106

Paul G. Arauz , Gabriela Garcia , Jose Llerena , Imin Kao

Despite fundamental biomechanical differences between the snatch and clean, few studies have systematically compared their mechanical and neuromuscular profiles in elite weightlifters, limiting evidence-based training and coaching strategies. This study examined full-body kinematics, vertical ground reaction forces, surface electromyography (EMG), and barbell kinematics in 10 elite athletes performing lifts at 80 % of their competition maximum. Consistent with our hypothesis, the clean exhibited a force-dominant profile, characterized by higher vertical ground reaction forces across most lift phases (e.g., 904.2 ± 99.72 N vs. 842.81 ± 109.32 N at the end of the first pull, p < 0.001), greater EMG activity in the biceps femoris, gastrocnemius, vastus lateralis, and gluteus during key phases (p < 0.05), and reduced vertical bar displacement (1.08 ± 0.06 m vs. 1.29 ± 0.06 m, p < 0.001), reflecting its emphasis on efficient load transfer and postural control during the catch. In contrast, the snatch demonstrated a velocity- and technique-dominant profile, with higher bar velocities (e.g., 2.06 ± 0.16 m/s vs. 1.58 ± 0.19 m/s at the end of the second pull, p < 0.001), greater hip and knee flexion and abduction, and pronounced external rotation of the hip and shoulder during early and terminal phases of the lift, respectively (p < 0.05). These findings emphasize the snatch’s reliance on rapid bar acceleration, technical precision, and precise intersegmental coordination. The snatch’s longer bar path and wider grip (1 ± 0.05 m vs. 0.58 ± 0.05 m, p < 0.001), further underscore its dependence on mobility, neuromuscular timing, and technical proficiency rather than maximal force output. These lift-specific biomechanical signatures provide a foundation for optimizing strength and power development, refining technical coaching cues, and informing injury-prevention strategies in high-performance weightlifting.

尽管抓举和挺举在生物力学上存在根本的差异，但很少有研究系统地比较了精英举重运动员的机械和神经肌肉特征，这限制了基于证据的训练和指导策略。这项研究检查了10名优秀运动员在80%的比赛最大值下进行举重的全身运动学、垂直地面反作用力、表面肌电图（EMG）和杠铃运动学。与我们的假设一致，清洁表现出力主导的轮廓，其特征是在大多数抬起阶段具有较高的垂直地面反作用力（例如，第一次牵拉结束时为904.2±99.72牛对842.81±109.32牛，p < 0.001），在关键阶段股二头肌、腓肠肌、股外侧肌和臀肌的肌电活动更大（p < 0.05），并且垂直杆位移减少（1.08±0.06米对1.29±0.06米，p < 0.001）。反映其重点在有效的负荷转移和姿态控制期间捕获。相比之下，抓举表现出速度和技术优势，杠铃速度更高（例如，第二次抓举结束时为2.06±0.16 m/s vs. 1.58±0.19 m/s, p < 0.001），髋关节和膝关节弯曲和外展更大，髋关节和肩部明显外旋，分别在抓举的早期和结束阶段（p < 0.05）。这些发现强调抓举依赖于快速的杆加速度、技术精度和精确的节间协调。抓举的更长的杆路和更宽的抓地力（1±0.05米vs 0.58±0.05米，p < 0.001）进一步强调了它对机动性、神经肌肉时机和技术熟练程度的依赖，而不是最大的力量输出。这些特定于举重的生物力学特征为优化力量和力量发展、完善技术指导线索和告知高性能举重的伤害预防策略提供了基础。

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