Journal of Electromyography and Kinesiology最新文献_第3页

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 : 2026-02-01 Epub 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

Optimal path for measurement of biceps femoris long head architecture using synchronized ultrasound and two-dimensional video probe kinematics 利用同步超声和二维视频探针运动学测量股二头肌长头结构的最佳路径

IF 2.3 4区医学 Q3 NEUROSCIENCES

Journal of Electromyography and Kinesiology

Pub Date : 2026-02-01 Epub Date: 2025-11-14 DOI: 10.1016/j.jelekin.2025.103086

Eleftherios Kellis, Georgios Salonikios, Athanasios Ellinoudis

The biceps femoris long head (BF) exhibits complex morphology, with fascicle orientation and aponeurotic curvature varying along its length. In vivo assessment of fascicle length (FL), pennation angle (PA), and muscle thickness (MT) is commonly performed with B-mode ultrasound (US), yet probe placement may confound interpretation of morphological variation. This study examined the effects of probe trajectory on BF architecture by synchronizing conventional B-mode US with two-dimensional kinematic tracking. Nineteen males were scanned in a side-lying position with the hip and knee flexed at 20°. B-mode US scans were performed along three paths: Central (center of the mediolateral width), 10 mm medial, and 10 mm lateral relative to Central. A high-speed camera tracked probe movement, synchronized with the US video. Measurements included FL, PA, and intermediate (IT) and full muscle thickness (MT) at four points along the muscle. Probe path significantly influenced FL and PA but not MT or IT. Medial and lateral scans produced longer fascicles and smaller PAs compared to the central path (p < 0.05). Differences in FL and PA exceeded 10 %, corresponding to ∼7–10 mm in FL and 2–3° in PA. These magnitudes equal or surpass values often attributed to training adaptations or injury-related remodeling. Probe trajectory can bias BF architectural estimates by amounts that rival physiologically meaningful changes, highlighting the need for standardized scanning protocols.

股二头肌长头（BF）表现出复杂的形态，其束状方向和腱膜曲率沿其长度变化。在体内评估肌束长度（FL）、笔尖角（PA）和肌肉厚度（MT）通常是用b超（US）进行的，但探针的放置可能会混淆形态学变化的解释。通过将传统的b模US与二维运动跟踪同步，研究了探针轨迹对BF结构的影响。19名男性采用侧躺姿势，臀部和膝盖弯曲20°进行扫描。B-mode US扫描沿三条路径进行：中央（中外侧宽度的中心），内侧10mm和相对于中央的外侧10mm。高速摄像机跟踪探针的运动，与美国视频同步。测量包括沿肌肉四个点的FL、PA、中间（IT）和全肌厚度（MT）。探针路径对FL和PA有显著影响，但对MT和IT无显著影响。与中央路径相比，内侧和外侧扫描产生更长的肌束和更小的PAs （p < 0.05）。FL和PA的差异超过10%，对应于FL为~ 7-10 mm， PA为2-3°。这些数值等于或超过通常归因于训练适应或损伤相关重塑的数值。探针轨迹可能会对BF架构的估计产生偏差，其数量可能与生理上有意义的变化相匹配，这突出了标准化扫描协议的必要性。

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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 : 2026-02-01 Epub 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

The influence of muscle shapes on HDsEMG decomposition yield and accuracy 肌肉形状对HDsEMG分解率和精度的影响

IF 2.3 4区医学 Q3 NEUROSCIENCES

Journal of Electromyography and Kinesiology

Pub Date : 2026-02-01 Epub Date: 2025-12-18 DOI: 10.1016/j.jelekin.2025.103103

Andra Oltmann , Jan Graßhoff , Tobias Knopp , Philipp Rostalski

The application of high-density surface electromyography in conjunction with decomposition algorithms has enabled decoding of motor unit (MU) firings. In developing such algorithms, model-based simulation is an established means to assess yield and accuracy. In this work, we therefore investigate how the simulated muscle shape impacts the decomposition performance.

To this end, an arm model with an anatomical biceps brachii shape was developed, and its plausibility in representing MU action potential waveforms was verified with decomposition of experimental, submaximal ramp contractions. From this anatomical muscle shape model, two simplified shapes were derived. In a simulation study, comparable fiber pathways and MU properties were used in anatomical and simplified muscle shape models, and a blind source separation-based decomposition was performed. The results were evaluated with respect to the number of identified MUs and their rate of agreement (RoA).

Across all models, MUs with the highest energy contribution were identified. For the two simplified shapes, statistically significantly more MUs (p

< 0.05

) were decomposed due to changed electrode-fiber distances, while the RoA remained consistently high above

94.63 \pm 12.16 %

indicating reliable MU property extraction with all three models. The results emphasize the benefit of anatomically accurate muscle shape models since small simplifications can affect decomposition yield.

高密度表面肌电图的应用与分解算法相结合，使运动单元（MU）放电的解码成为可能。在开发这种算法时，基于模型的仿真是评估产量和准确性的既定手段。在这项工作中，我们因此研究了模拟肌肉形状如何影响分解性能。为此，建立了一个具有肱二头肌解剖形状的手臂模型，并通过分解实验的次极大斜坡收缩来验证其表示MU动作电位波形的合理性。根据该解剖肌肉形态模型，导出了两种简化的肌肉形态。在一项仿真研究中，在解剖和简化的肌肉形状模型中使用了可比较的纤维通路和MU特性，并进行了基于盲源分离的分解。结果是评估相对于鉴定的MUs的数量和他们的协议率（RoA）。在所有模型中，确定了具有最高能量贡献的MUs。对于两种简化形状，由于电极-纤维距离的变化，分解的MU数量显著增加（p <0.05），而RoA始终保持在94.63±12.16%以上，表明三种模型提取的MU属性都是可靠的。结果强调解剖学上准确的肌肉形状模型的好处，因为小的简化会影响分解收率。

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引用次数: 0

Glenohumeral joint dynamics and rotator cuff health in youth manual wheelchair users with pediatric spinal cord injury and dysfunction 儿童脊髓损伤和功能障碍的青年手动轮椅使用者的盂肱关节动力学和肩袖健康

IF 2.3 4区医学 Q3 NEUROSCIENCES

Journal of Electromyography and Kinesiology

Pub Date : 2026-02-01 Epub Date: 2026-01-11 DOI: 10.1016/j.jelekin.2026.103108

Caleb M.A. Cordes , Alyssa J. Schnorenberg , Joshua M. Leonardis , Anthony V. Nguyen , Sergey Tarima , Karin S. Goodfriend , Mark J. England , Jonathan D. Samet , Shubhra Mukherjee , Amee L. Seitz , Brooke A. Slavens

Youth with pediatric-onset spinal cord injury or dysfunction (SCI/D) rely on manual wheelchairs for mobility throughout their lives, leading to prolonged shoulder loading during development and growth. While manual wheelchair use is known to accelerate shoulder degeneration in adults, the biomechanical factors contributing to structural shoulder pathology in youth remain poorly understood. We quantified how glenohumeral joint loading and movement variability during propulsion relates to rotator cuff structure and pathology in 34 youth manual wheelchair users with pediatric-onset SCI/D. Participants underwent motion analysis during wheelchair propulsion at a self-selected speed and shoulder ultrasound. Rotator cuff pathology was identified in 20.6% of participants. Some observed associations suggested that lower intersegmental glenohumeral joint forces and moments coincided with supraspinatus and subscapularis pathology. Similarly, variability in certain glenohumeral joint ranges of motion, forces, and moments was also associated with altered rotator cuff morphology. These findings support a bidirectional relationship between shoulder loading and pathology, suggesting functional and morphological adaptations to repetitive propulsion demands or early tissue compromise. Overall, this work underscores the complexity of shoulder biomechanics in youth manual wheelchair users and highlights the need for longitudinal, multivariate research to distinguish protective adaptations and disuse patterns from early indicators of tendon degeneration.

患有儿科脊髓损伤或功能障碍（SCI/D）的青少年一生都依赖手动轮椅进行活动，导致发育和生长过程中肩部负荷延长。虽然已知使用手动轮椅会加速成人肩关节退行性变，但对青少年肩关节结构性病理的生物力学因素仍知之甚少。我们量化了34例儿童发病SCI/D的青年手动轮椅使用者在推进过程中肩关节负荷和运动变异性与肩袖结构和病理的关系。参与者在轮椅推进过程中以自行选择的速度进行运动分析，并进行肩部超声检查。在20.6%的参与者中发现了肩袖病变。一些观察到的关联表明，下节段间肩胛关节力和力矩与冈上肌和肩胛下肌病理一致。类似地，某些盂肱关节活动范围、力和力矩的可变性也与肩袖形态的改变有关。这些发现支持了肩部负荷与病理之间的双向关系，表明重复推进需求或早期组织损害的功能和形态适应。总的来说，这项工作强调了青年手动轮椅使用者肩部生物力学的复杂性，并强调了纵向、多变量研究的必要性，以从肌腱退变的早期指标中区分保护性适应和停用模式。

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引用次数: 0

Real-time changes in rate of torque development and corticospinal excitability during transcutaneous spinal cord stimulation in healthy individuals 健康个体经皮脊髓刺激过程中扭矩发展速率和皮质脊髓兴奋性的实时变化

IF 2.3 4区医学 Q3 NEUROSCIENCES

Journal of Electromyography and Kinesiology

Pub Date : 2026-02-01 Epub Date: 2025-12-01 DOI: 10.1016/j.jelekin.2025.103096

Keita Takano , Tomofumi Yamaguchi , Kano Kikuma , Yamato Omi , Natsuki Katagiri , Takatsugu Sato , Shigeo Tanabe , Kaoru Honaga , Kunitsugu Kondo , Toshiyuki Fujiwara

Transcutaneous spinal cord stimulation (tSCS) is used to induce neural plasticity and enhance motor function recovery following a stroke. Examining real-time changes under tSCS regulation would provide comprehensive insights into the mechanisms underlying motor functional recovery and neural plasticity. However, the real-time changes in the rate of torque development and neural excitability during tSCS remain unclear. This study explored the real-time changes in the rate of torque development and corticospinal excitability during tSCS. Twenty healthy individuals participated in two separate experiments, each with a tSCS condition and control condition. Under the tSCS condition, tSCS was applied to the Th11–Th12 spinous processes at an intensity twice the sensory threshold of the trunk muscles. The peak rate of torque development in the explosive lower limb extension movement in Experiment 1 and motor-evoked potential (MEP) amplitudes in Experiment 2 were assessed before the intervention and with (tSCS condition) or without tSCS (control). The peak rate of torque development and MEP amplitudes increased during tSCS compared to before tSCS (P = 0.038 and 0.047, respectively). However, the control condition had no significant effect. These findings demonstrate that tSCS enhances the rate of torque development and increases corticospinal excitability in healthy individuals, offering valuable fundamental insights into tSCS mechanisms and potential neurorehabilitation applications.

经皮脊髓刺激（tSCS）用于诱导脑卒中后的神经可塑性和增强运动功能恢复。研究tSCS调控下的实时变化将为运动功能恢复和神经可塑性的机制提供全面的见解。然而，在tSCS期间，扭矩发展速度和神经兴奋性的实时变化尚不清楚。本研究探讨了tSCS过程中扭矩发展速率和皮质脊髓兴奋性的实时变化。20名健康个体参加了两个独立的实验，每个实验都有tSCS条件和对照条件。在tSCS条件下，tSCS以两倍于躯干肌肉感觉阈值的强度作用于Th11-Th12棘突。实验1的爆发性下肢伸展运动的扭矩发展峰值速率和实验2的运动诱发电位（MEP）振幅分别在干预前、tSCS条件下和无tSCS条件下进行评估。与tSCS前相比，tSCS期间扭矩发展峰值速率和MEP振幅均有所增加（P分别为0.038和0.047）。而对照条件无显著影响。这些发现表明，tSCS可以提高健康个体的扭矩发展速度和皮质脊髓兴奋性，为tSCS的机制和潜在的神经康复应用提供了有价值的基础见解。

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引用次数: 0

Quantifying the influence of radiation therapy on functional shoulder health indicators in breast cancer patients: An exploratory study 量化放疗对乳腺癌患者肩功能健康指标的影响：一项探索性研究。

IF 2.3 4区医学 Q3 NEUROSCIENCES

Journal of Electromyography and Kinesiology

Pub Date : 2025-12-01 Epub Date: 2025-09-10 DOI: 10.1016/j.jelekin.2025.103071

M.C.Herrera Valerio, C.R. Dickerson

Introduction: Radiotherapy is a highly effective treatment for breast cancer, but it is also associated with several complications that can impact quality of life and survivorship, including arm function. This study assessed the influence of radiation therapy on shoulder health indicators of breast cancer patients during their treatment period. Methods: Fourteen breast cancer patients undergoing radiation therapy participated. Shoulder health indicators were assessed at the baseline, midpoint, and endpoint of radiation treatment. The indicators included shoulder muscle activations, arm circumference, shoulder complex range of motion, and arm strength. Repeated measures ANOVAs followed by post-hoc Tukey-Kramer tests were used to identify differences in shoulder indicators between levels (p < 0.05). A multiple linear regression model was created for each dependent measurement including radiation dose and fractions as predictor variables. Results: The activation of the teres major and latissimus dorsi muscles decreased in most of the evaluated movements. Additionally, mean shoulder abduction decreased by 11 deg, and negative correlations existed between shoulder abduction range of motion and radiation dose, and between shoulder abduction strength and radiation fractions. The observed changes may relate to post-treatment inflammation, and lingering effects of radiation on shoulder health indicators may take longer to manifest, hindering identification within the treatment window.

简介：放疗是一种非常有效的乳腺癌治疗方法，但它也与一些影响生活质量和生存率的并发症相关，包括手臂功能。本研究评估放射治疗对乳腺癌患者治疗期间肩部健康指标的影响。方法：对14例接受放射治疗的乳腺癌患者进行研究。在放射治疗的基线、中点和终点评估肩部健康指标。指标包括肩部肌肉激活、手臂围度、肩部复杂活动范围和手臂力量。采用重复测量方差分析和事后Tukey-Kramer检验来确定不同水平之间肩部指标的差异(p)。结果：在大多数评估的运动中，大圆肌和背阔肌的激活减少。肩关节外展活动范围与放射剂量、肩关节外展强度与放射分量呈负相关。观察到的变化可能与治疗后的炎症有关，辐射对肩部健康指标的持续影响可能需要更长的时间才能显现出来，从而阻碍了在治疗窗口内的识别。

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引用次数: 0

Factors influencing instability during dual-task walking in stroke patients 影响脑卒中患者双任务行走不稳定性的因素。

IF 2.3 4区医学 Q3 NEUROSCIENCES

Journal of Electromyography and Kinesiology

Pub Date : 2025-12-01 Epub Date: 2025-10-26 DOI: 10.1016/j.jelekin.2025.103077

Ryuya Kitago , Naomichi Mizuta , Naruhito Hasui , Shu Morioka

Walking involves multitasking, and many individuals with stroke exhibit dual-task interference, gait instability, and altered lower limb muscle activity even during single-task walking. This study investigated dual-task interference in individuals with stroke and its relationship to single-task walking characteristics. A total of 30 participants completed single-task and dual-task walking. Correct response rate (CRR), dual-task effect, and percentage change in walking speed were assessed using inertial sensors and surface electromyography.

The root mean square (RMS) of trunk acceleration and the sample entropy of lower limb acceleration signals were computed. Higher CRR during walking (p = 0.048) and faster walking speed under single-task conditions (p < 0.001) were observed. Mean dual-task effect was − 32.2 %. RMS, sample entropy, and co-contraction index were elevated during dual-task walking (all p < 0.001).

Changes in walking speed were associated with co-contraction index (ρ = − 0.380, p = 0.039), RMS (ρ = − 0.764, p < 0.001), and sample entropy (ρ = − 0.734, p < 0.001).

Regression analysis indicated that single-task walking speed, RMS, and sample entropy predicted instability during dual-task walking (R² = 0.545).

These results suggest that compromised postural control during single-task walking increases susceptibility to cognitive interference, emphasizing the importance of targeted gait stability training.

行走涉及多任务处理，许多中风患者即使在单任务行走时也表现出双任务干扰、步态不稳定和下肢肌肉活动改变。本研究探讨脑卒中患者的双任务干扰及其与单任务行走特征的关系。共有30名参与者完成了单任务和双任务行走。采用惯性传感器和表面肌电图评估正确反应率（CRR）、双任务效应和步行速度变化百分比。计算躯干加速度的均方根和下肢加速度信号的样本熵。单任务条件下，行走时的CRR较高（p = 0.048），行走速度较快（p = 0.545）。这些结果表明，在单任务行走过程中，姿势控制受损会增加对认知干扰的易感性，强调了有针对性的步态稳定性训练的重要性。

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引用次数: 0

Comparison of muscle activity between isokinetic and iso-inertial exercise 等速运动和等惯性运动肌肉活动的比较

IF 2.3 4区医学 Q3 NEUROSCIENCES

Journal of Electromyography and Kinesiology

Pub Date : 2025-12-01 Epub Date: 2025-09-03 DOI: 10.1016/j.jelekin.2025.103052

Timothy H.T. Phillips , Ransi S.S. Subasinghe Arachchige , Roy T.H. Cheung

Background

Resistance training plays a crucial role in musculoskeletal rehabilitation and athletic performance. Traditional resistance training often underloads the eccentric phase, as muscles generate more force while lengthening. Isokinetic and iso-inertial exercises have been used to overcome this limitation, with both showing greater muscle activity compared to traditional methods, potentially leading to enhanced strength and hypertrophy. However, limited research compares the two modalities.

Methods

This randomised crossover study involved healthy adults between the ages of 18–45 years who performed isokinetic knee extensions and iso-inertial squats at fast and slow speeds. Electromyographic activity of the quadriceps was recorded, and the eccentric-to-concentric root-mean-square (RMS) ratio was calculated.

Results

Results showed that iso-inertial exercise at fast speeds led to a significantly greater eccentric-to-concentric RMS ratio in the rectus femoris (95 % CI 0.11 to 0.74; Cohen’s d = 0.89) and vastus lateralis (95 % CI 0.07 to 0.55, Cohen’s d = 0.75) compared to isokinetic exercise, with no difference in vastus medialis or at slow speeds.

Conclusion

Conclusion: These findings indicate that iso-inertial exercise induces greater eccentric muscle activity in key quadriceps muscles at fast speeds, suggesting its potential for enhancing eccentric overload and muscle strength gains.

背景：阻力训练在肌肉骨骼康复和运动表现中起着至关重要的作用。传统的阻力训练通常会使离心阶段负荷不足，因为肌肉在拉伸时产生更多的力量。等速运动和等惯性运动已被用于克服这一限制，与传统方法相比，两者都显示出更大的肌肉活动，潜在地导致力量增强和肥大。然而，比较这两种模式的研究有限。方法：这项随机交叉研究纳入了年龄在18-45岁之间的健康成年人，他们在快、慢速度下进行等速膝关节伸展和等速惯性深蹲。记录股四头肌肌电活动，计算偏心与同心均方根（RMS）比。结果结果显示，与等速运动相比，快速等惯性运动导致股直肌（95% CI 0.11 ~ 0.74, Cohen’s d = 0.89）和股外侧肌（95% CI 0.07 ~ 0.55, Cohen’s d = 0.75）的离心-同轴RMS比显著增大，而股内侧肌和慢速运动无差异。结论：这些结果表明，等惯性运动在快速运动时可诱导关键股四头肌的偏心肌活动，提示其可能增强偏心过载和肌肉力量的增加。

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引用次数: 0

Optimizing passive exoskeleton torque for dynamic overhead work: Phase-specific analysis on muscle activity and perceived exertion 优化被动外骨骼扭矩动态顶工作：肌肉活动和感知消耗的阶段特定分析

IF 2.3 4区医学 Q3 NEUROSCIENCES

Journal of Electromyography and Kinesiology

Pub Date : 2025-12-01 Epub Date: 2025-09-10 DOI: 10.1016/j.jelekin.2025.103070

Giulia Casu , Alan Barr , Sunwook Kim , Maury A. Nussbaum , David Rempel , Massimiliano Pau , Carisa Harris-Adamson

Purpose: This study investigated how different levels of torque provided by a passive arm-support exoskeleton (ASE) influence upper extremity muscle activity, perceived exertion, and fatigue during arm ascent and descent phases of a Dynamic Overhead (DO) task. Methods: The DO task involved 20 cycles of simulated drilling and was completed by 20 individuals by using a light-duty drill in four conditions: without supporting torque (no ASE) and with three increasing levels of ASE torque (i.e., 50, 75, and 100% of the torque required to support the arm in 90° of flexion). Surface electromyography was measured bilaterally over six shoulder muscles. Moreover, participants indicated torque preference, ratings of perceived exertion (RPE), and fatigue in the shoulder. Results: Increasing torque levels caused significant reductions in shoulder agonist muscle activity (up to 47%) and significant decreases in RPE and fatigue during the ascent phase. In contrast, higher levels of torque increased muscular activity for some antagonist muscles during the descent phase. Conclusions: While torque levels of 75% and 100% received the most positive ratings, we suggest that 75% torque could be an effective supporting condition, by reducing shoulder muscle flexor activity during arm ascent and minimizing antagonist muscle activity during arm descent.

目的：本研究调查了被动臂支撑外骨骼（ASE）提供的不同水平的扭矩如何影响动态架空（DO）任务中上肢肌肉活动、感知劳累和上肢疲劳。方法：DO任务包括20个模拟钻孔循环，由20个人使用轻型钻头在四种条件下完成：无支撑扭矩（无ASE）和三种增加的ASE扭矩（即支持手臂90°弯曲所需的扭矩的50%，75%和100%）。测量两侧六块肩部肌肉的表面肌电图。此外，参与者还指出了扭矩偏好、感知用力等级（RPE）和肩部疲劳。结果：增加扭矩水平导致肩激动剂肌肉活动显著减少（高达47%），在上升阶段RPE和疲劳显著减少。相反，在下降阶段，较高的扭矩水平增加了一些拮抗肌的肌肉活动。结论：虽然75%和100%的扭矩水平得到了最积极的评价，但我们认为75%的扭矩可以是一个有效的支持条件，通过减少手臂上升过程中肩部肌肉屈肌的活动，并减少手臂下降过程中拮抗剂肌肉的活动。

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引用次数: 0