Journal of Electromyography and Kinesiology最新文献_第2页

Gait pathomechanics in early-stage knee osteoarthritis: do non-traumatic and post-traumatic patients walk differently? 早期膝关节骨关节炎的步态病理力学：非创伤和创伤后患者行走方式不同吗？

IF 2.3 4区医学 Q3 NEUROSCIENCES

Journal of Electromyography and Kinesiology

Pub Date : 2026-01-28 DOI: 10.1016/j.jelekin.2026.103113

Anna Vanmechelen , Miel Willems , Bryce A. Killen , Pieter Berger , Hilde Vandenneucker , Kurt De Vlam , Ilse Jonkers , Annemie Smeets , Jos Vanrenterghem , Sabine Verschueren

Altered knee joint loading in early-stage osteoarthritis may accelerate cartilage degeneration and symptom progression. This cross-sectional observational study investigates differences in knee joint pathomechanics between 22 patients with early-stage post-traumatic knee osteoarthritis (PTOA), 26 patients with early-stage non-traumatic knee osteoarthritis (NTOA) and 20 age-/gender-matched healthy controls. Participants walked barefoot at self-selected speeds while marker data (100 Hz), ground reaction forces (1000 Hz), and surface electromyography (1000 Hz) were recorded. electromyography-informed musculoskeletal simulations estimated knee contact forces (KCF) and joint mechanics. Group differences in these outcomes and measured muscle activations were assessed via Statistical Parametric Mapping t-tests. Analysis of Covariance investigated the influence of covariates (age, gender, gait speed, alignment, strength). Early-stage NTOA and PTOA patients exhibit similar KCF and joint mechanics. Both patient groups exhibited significantly reduced second KCF peaks compared to controls (p = 0.019, Δmean NTOA – controls = 1.07 BW, Δmean PTOA – controls = 0.98 BW), suggesting knee underloading, in contrast to the joint overload typically seen in established OA. Additionally, gait speed significantly influenced KCF peaks. These findings suggest that early OA may be characterized by cartilage underloading. Longitudinal studies and more demanding tasks may reveal phenotype-specific biomechanical distinctions and also confirm continuous cartilage underloading in disease progression.

早期骨关节炎的膝关节负荷改变可能加速软骨退变和症状进展。本横断面观察性研究调查了22例早期创伤后膝骨关节炎（PTOA）患者、26例早期非创伤性膝骨关节炎（NTOA）患者和20例年龄/性别匹配的健康对照者膝关节病理力学的差异。参与者以自己选择的速度赤脚行走，同时记录标记数据（100赫兹）、地面反作用力（1000赫兹）和表面肌电图（1000赫兹）。肌电图信息的肌肉骨骼模拟估计膝关节接触力（KCF）和关节力学。通过统计参数映射t检验评估这些结果和测量肌肉激活的组间差异。协方差分析调查了协变量（年龄、性别、步态速度、对齐、力量）的影响。早期NTOA和PTOA患者表现出相似的KCF和关节力学。与对照组相比，两组患者的第二次KCF峰值均显著降低（p = 0.019， Δmean NTOA -对照组= 1.07 BW， Δmean PTOA -对照组= 0.98 BW），提示膝关节负荷不足，而不是关节炎患者通常出现的关节过载。此外，步态速度显著影响KCF峰值。这些发现提示早期骨关节炎可能以软骨负荷过低为特征。纵向研究和更苛刻的任务可能揭示表型特异性的生物力学差异，也证实了疾病进展中持续的软骨负荷不足。

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引用次数: 0

Investigating text neck syndrome and duration of mobile phone use, muscle activity, hand grip strength, posture, and disability 调查短信颈综合征与手机使用时间、肌肉活动、手握力、姿势和残疾的关系

IF 2.3 4区医学 Q3 NEUROSCIENCES

Journal of Electromyography and Kinesiology

Pub Date : 2026-01-26 DOI: 10.1016/j.jelekin.2026.103110

Zeynal Yasaci , Emrah Zirek , Rustem Mustafaoglu , Arzu Razak Ozdincler

Neck and shoulder musculoskeletal symptoms related to smartphone use are becoming increasingly prevalent, yet the underlying mechanisms including smartphone usage duration, muscle activity, hand grip strength, posture, and disability remain incompletely understood. This study examined the interaction between text-neck syndrome and factors such as smartphone usage duration, muscle activity, hand grip strength, posture, and disability. Forty participants (Text Neck group: n = 18; 14 females or Control group: n = 22; 15 females) underwent neuromuscular assessment. Surface electromyography measured bilateral muscle activity in the upper trapezius (UT) and abductor pollicis brevis (APB) muscles during smartphone use. Secondary outcomes included the Visual Analogue Scale (VAS) to assess pain intensity, hand grip strength, New York Posture Rating Scale (NYPRS), Neck Disability Index (NDI), and Disabilities of the Arm, Shoulder, and Hand (DASH) questionnaire. The Text Neck group demonstrated significantly higher smartphone use (p < 0.001), higher texting time (p = 0.006), and lower muscle activation at activity in the dominant APB (p = 0.011), dominant UT (p < 0.001), and non-dominant UT (p = 0.008). These findings provide novel insights into how excessive smartphone use alters muscle function and postural alignment in individuals with text-neck syndrome. Understanding these mechanisms may inform targeted prevention and rehabilitation strategies to mitigate musculoskeletal risk associated with modern technology use.

与智能手机使用相关的颈部和肩部肌肉骨骼症状正变得越来越普遍，但包括智能手机使用时间、肌肉活动、手握力、姿势和残疾在内的潜在机制仍未完全了解。这项研究调查了短信脖综合征与智能手机使用时间、肌肉活动、手握力、姿势和残疾等因素之间的相互作用。40名参与者（短信脖组：n = 18； 14名女性或对照组：n = 22； 15名女性）接受了神经肌肉评估。使用智能手机时，表面肌电图测量了双侧斜方肌上部（UT）和拇短外展肌（APB）的肌肉活动。次要结果包括评估疼痛强度的视觉模拟量表（VAS）、手部握力、纽约姿势评定量表（NYPRS）、颈部残疾指数（NDI）和手臂、肩部和手部残疾（DASH）问卷。文本颈组表现出更高的智能手机使用率（p < 0.001），更长的发短信时间（p = 0.006），以及在优势APB (p = 0.011)，优势UT （p < 0.001）和非优势UT （p = 0.008）活动时更低的肌肉激活。这些发现为过度使用智能手机如何改变短信脖综合征患者的肌肉功能和姿势提供了新的见解。了解这些机制可以为有针对性的预防和康复策略提供信息，以减轻与现代技术使用相关的肌肉骨骼风险。

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引用次数: 0

Instruction during lifting: How analogy and explicit instruction influence performance and motor control 举重过程中的指导：类比和显性指导如何影响运动性能和运动控制。

IF 2.3 4区医学 Q3 NEUROSCIENCES

Journal of Electromyography and Kinesiology

Pub Date : 2026-01-13 DOI: 10.1016/j.jelekin.2026.103106

Angel Carnero-Diaz , Matt Greig , David Wing , Javier Pecci

Purpose

This study aimed to examine the effects of analogy (ANA) and explicit (EXP) verbal instruction on motor performance and muscle activation during a weightlifting task. Traditional coaching strategies often rely on explicit cues; however, recent research suggests that analogy-based instructions may offer a more efficient route to motor learning by promoting implicit control.

Scope

Twenty novice participants were randomly assigned to one of three conditions (ANA, EXP, or control), with the sequence of conditions counterbalanced across three consecutive days. Day 1 involved familiarization; Day 2 included the control and first experimental condition; and Day 3 completed the second experimental condition. Participants performed both isometric and dynamic lifting tasks while muscle activity (EMG), force production, and declarative knowledge were assessed using a within-participant design.

Conclusions

Results revealed significant alterations in lower limb EMG activity following both instructional strategies (p < 0.05), indicating a reorganization of motor control. Moreover, the EXP group exhibited significantly lower rate of force development within the first 200 ms compared to the control (p < 0.05). Overall force output was also higher in the control group. These findings suggest that avoiding verbal instruction may benefit maximal force production. However, analogy instructions appear to maintain performance levels while altering neuromuscular strategies.

Clinical trial register number ANZCTR (code: 386738).

目的：本研究旨在探讨类比（ANA）和显性（EXP）口头指导对举重运动表现和肌肉激活的影响。传统的教练策略往往依赖于明确的线索；然而，最近的研究表明，基于类比的指令可能通过促进内隐控制为运动学习提供更有效的途径。范围：20名新手参与者被随机分配到三种条件（ANA， EXP或control）中的一种，条件序列在连续三天内平衡。第一天是熟悉；第2天包括对照组和第一个实验条件；第3天完成第二个实验条件。参与者同时执行等长和动态举重任务，同时使用参与者内部设计评估肌肉活动（EMG），力产生和陈述性知识。结论：结果显示两种教学策略对下肢肌电图活动的影响显著

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引用次数: 0

Sex differences in myoelectric manifestations of shoulder fatigue in time–frequency and complexity domains during a repetitive shoulder height task 重复性肩高任务时肩疲劳的肌电表现在时间频率和复杂性域的性别差异

IF 2.3 4区医学 Q3 NEUROSCIENCES

Journal of Electromyography and Kinesiology

Pub Date : 2026-01-11 DOI: 10.1016/j.jelekin.2026.103109

Yiyang Chen , Di Kang , Julie N. Côté

Previous studies have shown sex differences in muscle activation amplitude and frequency spectrum during fatiguing shoulder-height tasks. However, time–frequency and complexity analyses may reveal new features of the shoulder’s injury exposure with fatigue, but have never been compared between sexes. Fifty-five (29 females) asymptomatic young adults performed a repetitive, forward–backward shoulder height task until scoring 8/10 on a Borg CR10 scale while surface electromyography (EMG) of upper trapezius, anterior deltoid, biceps brachii, and triceps brachii was recorded. Findings show that 1) all muscles displayed decreased sample entropy and mean frequency with fatigue; 2) fatigue led to decreased major frequency (i.e., frequency with the highest power on the wavelet scalogram) of anterior deltoid, biceps brachii, and triceps but not upper trapezius; 3) females’ biceps brachii mean frequency and complexity were significantly higher than males’; all other frequency components were similar between sexes; 4) females showed significantly lower complexity of anterior deltoid. Results suggest that entropy and continuous wavelet transform analyses are capable of revealing new effects of sex and fatigue in myoelectric manifestations of repetitive shoulder tasks. This information may be useful towards modeling shoulder joint loads and predicting sex-specific shoulder injury risks in future applications.

先前的研究表明，在肩部高度的疲劳任务中，肌肉激活幅度和频谱存在性别差异。然而，时间频率和复杂性分析可能揭示了疲劳肩关节损伤暴露的新特征，但从未在性别之间进行过比较。55名（29名女性）无症状的年轻人进行了重复的前后肩高任务，直到在Borg CR10量表上获得8/10分，同时记录了上斜方肌、前三角肌、肱二头肌和肱三头肌的表面肌电图（EMG）。结果表明：1)随着疲劳，所有肌肉的样本熵和平均频率均下降；2)疲劳导致前三角肌、肱二头肌和肱三头肌的主频率（即小波谱上功率最大的频率）下降，而斜方肌上部没有下降；3)雌性肱二头肌平均出现频率和复杂程度显著高于雄性；所有其他频率成分在性别之间相似；4)女性前三角肌复杂性明显降低。结果表明，熵和连续小波变换分析能够揭示性别和疲劳对重复性肩部任务肌电表现的新影响。在未来的应用中，这些信息可能有助于建立肩关节负荷模型和预测性别特异性肩关节损伤风险。

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引用次数: 0

Reproducibility of bioimpedance spectroscopy parameters to evaluate skeletal muscle properties 生物阻抗谱参数评价骨骼肌特性的再现性

IF 2.3 4区医学 Q3 NEUROSCIENCES

Journal of Electromyography and Kinesiology

Pub Date : 2026-01-11 DOI: 10.1016/j.jelekin.2026.103107

Silvère De Freitas , Alain Letourneur , Jérémie Bouvier , Alexandre Fouré , Etienne Gouraud

Bioimpedance spectroscopy (BIS) can be used to evaluate skeletal muscle hydration and integrity in healthy and injured skeletal muscle, thanks to resistance and reactance variations. However, skeletal muscle measurements reproducibility and the effect of length changes have not been evaluated. The aim of this study was to assess the reproducibility and the effect of knee angle on BIS measurements in the knee extensor. Healthy males participated in two experimental sessions, whole-body BIS measurements at rest, isometric maximal voluntary torque (T_max), and BIS assessments at five knee angles (20°, 40°, 60°, 80° and 100° − full extension: 0°) at rest and during T_max. Reproducibility was evaluated with intra-class correlation coefficient (ICC) and coefficient of variation (CV). Whole-body BIS displayed moderate to very good reproducibility at rest (ICC: 0.56–0.82; CV: 3.8–15.4 %). Knee extensors BIS parameters showed a good reproducibility at rest (ICC: 0.53–0.94 and CV: 2.8–8.0 %) and were affected by muscle length, with an increase in intracellular resistance, membrane capacitance and a decrease in characteristic frequency at long muscle lengths (p < 0.05). Whole-body and local BIS parameters showed reproducibility values suitable for daily practice. These parameters are modified by knee angle suggesting a dependency to structural changes of the skeletal muscle.

生物阻抗光谱（BIS）可用于评估骨骼肌水化和完整性在健康和受伤的骨骼肌，由于阻力和电抗的变化。然而，骨骼肌测量的可重复性和长度变化的影响尚未得到评估。本研究的目的是评估膝关节角度对膝关节伸肌BIS测量的可重复性和影响。健康男性参加了两个实验阶段，静止时的全身BIS测量，等长最大自主扭矩（Tmax），以及静止和Tmax时五个膝关节角度（20°，40°，60°，80°和100°-完全伸展：0°）的BIS评估。用类内相关系数（ICC）和变异系数（CV）评价重现性。全身BIS在静止状态下显示出中等至非常好的重现性（ICC: 0.56-0.82; CV: 3.8 - 15.4%）。静息状态下，膝关节伸肌BIS参数具有良好的再现性（ICC: 0.53-0.94, CV: 2.8 - 8.0%），且受肌长影响，在肌长状态下，细胞内阻力、膜电容增加，特征频率降低（p < 0.05）。全身和局部BIS参数显示适合日常练习的重复性值。这些参数被膝关节角度修改，提示骨骼肌结构变化的依赖性。

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引用次数: 0

Estimating IMU signals from surface EMG using physics-informed and domain-adaptive neural networks 利用物理信息和领域自适应神经网络估计表面肌电的IMU信号

IF 2.3 4区医学 Q3 NEUROSCIENCES

Journal of Electromyography and Kinesiology

Pub Date : 2026-01-10 DOI: 10.1016/j.jelekin.2026.103105

Hari Iyer, Heejin Jeong

We propose a physics-informed, domain-adaptive neural network architecture for estimating body kinematics from surface electromyography (EMG) signals across heterogeneous human task domains. The proposed approach addresses the biomechanical inverse mapping problem by predicting inertial measurement unit (IMU) outputs at the window level directly from segmented and normalized EMG inputs, without requiring domain-specific tuning or retraining. The model employs a shared convolutional feature extractor followed by two branches: a primary regression head that predicts mean IMU signals and a domain-classification head trained adversarially using a gradient reversal layer. This architecture encourages the learning of task-invariant representations while preserving discriminative capacity for accurate motion prediction. To enforce biomechanical plausibility, we introduce a physics-informed loss term that penalizes the first derivative of the predicted acceleration (i.e., jerk), thereby reducing unrealistic dynamics. The model was evaluated using EMG-IMU data collected across five distinct task categories with varied sensor configurations. The proposed approach achieved a root mean squared error of 0.42 ± 0.11 m/s² for acceleration and 6.38 ± 1.1°/s for gyroscope outputs across 57 IMU output channels, corresponding to approximately 23% and 2.7% of peak amplitudes, respectively. Domain prediction accuracy reached nearly 75%, with per-class precision, recall, and F1 scores varying as a function of domain complexity and the degree of overlap in EMG activation and motion patterns across task domains.

我们提出了一种物理信息，领域自适应的神经网络架构，用于从异质人类任务域的表面肌电图（EMG）信号中估计身体运动学。该方法通过直接从分割和归一化的肌电信号输入中预测窗口级的惯性测量单元（IMU）输出来解决生物力学逆映射问题，而不需要特定领域的调整或再训练。该模型采用了一个共享的卷积特征提取器，随后有两个分支：一个预测平均IMU信号的主回归头和一个使用梯度反转层对抗性训练的域分类头。这种结构鼓励学习任务不变表示，同时保留准确运动预测的判别能力。为了加强生物力学的合理性，我们引入了一个物理信息损失项，惩罚预测加速度的一阶导数（即，震动），从而减少了不现实的动力学。该模型使用从五个不同任务类别和不同传感器配置中收集的肌电- imu数据进行评估。该方法实现了57个IMU输出通道的加速度和陀螺仪输出的均方根误差分别为0.42±0.11 m/s2和6.38±1.1°/s，分别相当于峰值振幅的23%和2.7%。领域预测准确率接近75%，每类精度、召回率和F1分数随领域复杂性和跨任务领域的肌电激活和运动模式重叠程度的变化而变化。

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引用次数: 0

Motor adaptations during stair ascent and descent in individuals with chronic primary low back pain 慢性原发性腰痛患者上下楼梯时的运动适应

IF 2.3 4区医学 Q3 NEUROSCIENCES

Journal of Electromyography and Kinesiology

Pub Date : 2025-12-21 DOI: 10.1016/j.jelekin.2025.103101

Guillaume Vadez , Eléna Payen Schalkens , Rubens A. da Silva , Louis-David Beaulieu , Hugo Massé-Alarie , Gabriel Moisan , Jacques Abboud

Altered neuromuscular strategies, such as lumbar muscle activity spatial redistribution, have been observed in individuals with chronic primary low back pain (CLBP), particularly during intense isometric efforts, but not during low-effort functional tasks. This cross-sectional study aimed to determine whether lumbar muscle activity distribution and trunk kinematics differ between individuals with CLBP and healthy controls during a dynamic, moderate-effort task, namely stair ascent and descent, and to investigate the relationship between muscle activity distribution and psychological factors of CLBP. Forty adults (20 CLBP, 20 controls) completed stair ambulation trials while lumbar high-density surface electromyography and kinematic data were recorded. Spatial redistribution and RMS amplitudes of electromyography were analyzed during ascent and descent, and across swing and stance phases. Participants with CLBP exhibited spatial redistribution of muscle activity on the left side during both phases of ascent, and during the swing phase of descent. Higher RMS amplitudes were observed bilaterally in CLBP participants across all tasks and phases, except during the stance phase of descent. No kinematic differences were found between groups. No relationship was found between muscle redistribution activity and psychological factors. These results suggest that CLBP participants exhibit altered neuromuscular strategies during stair ambulation, a moderately challenging functional task.

神经肌肉策略的改变，如腰肌活动空间再分配，已经在慢性原发性腰痛（CLBP）患者中观察到，特别是在高强度的等长运动中，而不是在低强度的功能任务中。本横断面研究旨在确定CLBP患者与健康对照者在进行动态、中等强度的爬楼梯任务时腰肌活动分布和躯干运动学是否存在差异，并探讨肌肉活动分布与CLBP心理因素之间的关系。40名成人（20名CLBP， 20名对照）完成楼梯行走试验，同时记录腰椎高密度表面肌电图和运动学数据。在上升和下降、摇摆和站立阶段分析肌电图的空间再分布和均方根振幅。患有CLBP的参与者在上升和下降的摇摆阶段都表现出左侧肌肉活动的空间再分布。CLBP参与者在所有任务和阶段均观察到较高的均方根幅值，除了在下降的站立阶段。各组间未发现运动学差异。肌肉再分配活动与心理因素没有关系。这些结果表明，CLBP参与者在楼梯行走时表现出改变的神经肌肉策略，这是一项中等挑战性的功能任务。

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引用次数: 0

Countermovement jumps with a weighted vest elicit post-activation performance enhancement among active males and females 反动作跳跃与加权背心引起激活后的表现增强在活跃的男性和女性。

IF 2.3 4区医学 Q3 NEUROSCIENCES

Journal of Electromyography and Kinesiology

Pub Date : 2025-12-20 DOI: 10.1016/j.jelekin.2025.103104

Rebekah Trent , Kate Hendrickson , Warren Joseph , Seth Pearson , Ward C. Dobbs , Kanikkai Steni Balan Sackiriyas , Thomas G. Almonroeder

Enhanced performance following a voluntary neuromuscular activation or conditioning activity is commonly referred to as post-activation performance enhancement (PAPE). Performing countermovement jumps (CMJs) with a weighted vest has the potential to elicit a PAPE effect, as the added load may facilitate acute neuromuscular changes. The primary purpose of this study was to assess whether performing CMJs with a weighted vest is associated with short-term changes in CMJ performance consistent with PAPE. 15 males and 14 females completed CMJs without additional load (baseline), while wearing a weighted vest with 10 % body mass load, and shortly after removing the weighted vest (post). Ground reaction force data recorded during CMJs were used to derive various force–time and jump performance metrics. Compared to baseline, males exhibited increases in peak velocity (+3.4 %), peak power (+4.3 %), jump height (+8.1 %), and reactive strength (+17.6 %) for the post condition. Females exhibited similar increases in peak velocity (+2.5 %), peak power (+3.6 %), jump height (+5.7 %), and reactive strength (+7.8 %). Changes in peak force were not significant. These findings suggest that performing CMJs with a weighted vest may acutely enhance subsequent jump performance, with improvements appearing to be driven more by increases in movement velocity than changes in force production.

自发性神经肌肉激活或调节活动后的性能增强通常被称为激活后性能增强（PAPE）。负重背心进行反向运动跳跃（CMJs）有可能引发PAPE效应，因为增加的负荷可能促进急性神经肌肉变化。本研究的主要目的是评估使用加权背心进行CMJ是否与与PAPE一致的CMJ表现的短期变化有关。15名男性和14名女性在没有额外负荷（基线）的情况下完成了CMJs，同时穿着体重负荷为10%的加重背心，并在脱下加重背心后不久完成了CMJs。在CMJs期间记录的地面反作用力数据用于推导各种力-时间和跳跃性能指标。与基线相比，男性在岗位条件下表现出峰值速度（+ 3.4%）、峰值功率（+ 4.3%）、跳跃高度（+ 8.1%）和反应强度（+ 17.6%）的增加。雌性表现出类似的峰值速度（+ 2.5%）、峰值功率（+ 3.6%）、跳跃高度（+ 5.7%）和反应强度（+ 7.8%）的增加。峰值力变化不显著。这些研究结果表明，在负重背心的情况下进行CMJs可能会显著提高随后的跳跃表现，这种改善似乎更多地是由运动速度的增加而不是力量产生的变化所驱动的。

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引用次数: 0

Measurement of maximal voluntary isometric lower limb muscle strength using a hand-held dynamometer in a non-injured healthy population: A systematic review of reference values, protocols, and sex differences 在未受伤的健康人群中使用手持式测力仪测量最大自主等距下肢肌力：参考值、方案和性别差异的系统回顾

IF 2.3 4区医学 Q3 NEUROSCIENCES

Journal of Electromyography and Kinesiology

Pub Date : 2025-12-20 DOI: 10.1016/j.jelekin.2025.103102

Mariana B. Machado , Ana Louise. R. de Carvalho , Ingara Schindler , Paulo Canas Rodrigues , Micheli B. Saquetto , Gustavo Leporace , Fabio L. Arcanjo , Mansueto Gomes-Neto

Although hand-held dynamometers are increasingly used in clinical practice, no systematic review has yet detailed the protocols for their use or thoroughly analyzed the results obtained. Objective: This study aimed to conduct a systematic review and meta-analysis to compile reference values for maximal voluntary isometric strength of the lower limbs, as measured with handheld dynamometry, in healthy individuals. The goal was to provide useful normative data for clinical strength assessments and to examine variations in measurement protocols and differences related to sex across different age groups. Methods: Searches were performed in MEDLINE/PubMed, Scopus, PEDro, and CINAHL from inception to April 2025. Two independent reviewers screened the studies, extracted the data, and assessed the methodological quality of the included studies. Meta-analysis was conducted, and the pooled data were presented using the standardized mean difference and 95 % confidence intervals. Results: We included 19 studies with 4,854 non-injured participants from 10 different countries. From the included studies, data on maximal voluntary isometric lower limb muscle strength were extracted and synthesized according to age group and sex. We found a relatively limited number of studies (n = 5) that proposed reference equations. Conclusions: This systematic review provides the most up-to-date sex- and age-specific reference values for measuring muscle strength using isometric handheld dynamometry. Additionally, we provide practical instructions for using manual dynamometry in the lower limbs.

尽管手持式测功机在临床实践中越来越多地使用，但尚未有系统的综述详细说明其使用方案或彻底分析所获得的结果。目的：本研究旨在进行系统回顾和荟萃分析，以编制健康人手持式测力仪测量的最大自主下肢等长力量的参考值。目的是为临床强度评估提供有用的规范性数据，并检查不同年龄组中测量方案的变化和与性别相关的差异。方法：在MEDLINE/PubMed、Scopus、PEDro和CINAHL中进行检索，检索时间为建站至2025年4月。两名独立审稿人筛选研究，提取数据，并评估纳入研究的方法学质量。进行meta分析，合并数据采用标准化均差和95%置信区间表示。结果：我们纳入了19项研究，涉及来自10个不同国家的4,854名未受伤的参与者。从纳入的研究中，根据年龄组和性别提取并综合了最大自主等长下肢肌力的数据。我们发现相对有限数量的研究（n = 5）提出了参考方程。结论：本系统综述提供了最新的性别和年龄特定的参考值测量肌肉力量使用等长手持测力仪。此外，我们还提供了在下肢使用手动测力法的实用指导。

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引用次数: 0

Task failure reveals range-dependent neuromuscular fatigue in shoulder muscles during arm elevation 任务失败揭示了手臂抬高时肩部肌肉的范围依赖性神经肌肉疲劳。

IF 2.3 4区医学 Q3 NEUROSCIENCES

Journal of Electromyography and Kinesiology

Pub Date : 2025-12-07 DOI: 10.1016/j.jelekin.2025.103100

Kara-Lyn Harrison, Rebecca Franklin, Trisha Scribbans

Repeated upper limb performance fatigues periscapular and/or rotator cuff muscles, which may alter humeral and scapular kinematics leading to increased subacromial impingement syndrome risk. However, the specific changes in neuromuscular patterns across different phases of a functional movement performed to failure remain unclear. This study investigated neuromuscular fatigue during a repeated arm elevation task to failure in asymptomatic individuals. Participants elevated their dominant arm while holding ∼ 30 % of their maximal isometric shoulder flexion load until task failure. High-density surface electromyography (HD-sEMG) was recorded from the pectoralis major (PM), biceps brachii (BB), and trapezius (UT, MT, LT) to accurately identify innervation zones and to enhance signal validity, while bipolar sEMG collected from the deltoid (AD, LD, PD), serratus anterior (SA) and infraspinatus (IN). Root mean square (RMS, %MVIC) and mean power frequency (MPF) were analyzed between three ranges of arm elevation (bottom, middle, top) at baseline and failure. During the middle and top ranges of arm elevation at task failure increased sEMG amplitude and/or decreased MPF of the PM, AD, BB, SA, LD, IN, UT, and MT were present. These results reveal that neuromuscular fatigue was highly dependent on the range of motion, with significant interactions showing that fatigue-related increases in RMS and decreases in MPF were most prominent in the middle and top ranges. These findings suggest that muscle function is altered precisely within the ranges where impingement risk is greatest, providing a potential neuromuscular basis for fatigue-related injury. Building off of these results, future work should use advanced techniques like high-density EMG and shear wave elastography to define how these fatigue-related changes in neuromuscular responses influence motor unit recruitment strategies, muscle force production, and subsequent alterations to SAS and injury risk.

反复的上肢活动使肩胛骨周围和/或肩袖肌肉疲劳，这可能改变肱骨和肩胛骨的运动学，从而增加肩峰下撞击综合征的风险。然而，在功能性运动的不同阶段，神经肌肉模式的具体变化仍然不清楚。本研究调查了无症状个体在重复手臂抬高任务期间的神经肌肉疲劳。参与者抬起主臂，同时保持最大等距肩部屈曲负荷的30%，直到任务失败。采集胸大肌（PM）、肱二头肌（BB）和斜方肌（UT、MT、LT）的高密度表面肌电图（HD-sEMG），准确识别神经支配区，增强信号有效性；采集三角肌（AD、LD、PD）、前锯肌（SA）和棘下肌（IN）的双极肌电图。均方根（RMS, %MVIC）和平均工频（MPF）在基线和失效时的三个臂高度范围（底部、中间、顶部）之间进行分析。在任务失败时手臂抬高的中间和顶部范围内，出现了PM、AD、BB、SA、LD、IN、UT和MT的表面肌电信号振幅增加和/或MPF降低。这些结果表明，神经肌肉疲劳高度依赖于运动范围，显著的相互作用表明，疲劳相关的RMS增加和MPF减少在中高范围最为突出。这些发现表明，在撞击风险最大的范围内，肌肉功能发生了精确的改变，为疲劳相关损伤提供了潜在的神经肌肉基础。在这些结果的基础上，未来的工作应该使用高密度肌电图和横波弹性图等先进技术来定义神经肌肉反应中这些与疲劳相关的变化如何影响运动单元招募策略、肌肉力量产生以及随后对SAS和损伤风险的改变。

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