990 results match your criteria muscle coactivation

Muscle co-contractions are greater in older adults during walking at self-selected speeds over uneven compared to even surfaces.

J Biomech 2021 Aug 28;128:110718. Epub 2021 Aug 28.

Department of Biomedical Engineering, New Jersey Institute of Technology, Newark, NJ, United States; Department of Electrical and Computer Engineering, New Jersey Institute of Technology, Newark, NJ, United States. Electronic address:

Falls in the aging population are a major public health concern. Outdoor falls in community-dwelling older adults are often triggered by uneven pedestrian walkways. Our understanding of the motor control adaptations to walk over an uneven surface, and the effects of aging on these adaptations is sparse. Read More

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Six-Week Remodeled Bike Pedal Training Improves Dynamic Control of Lateral Shuffling in Athletes With Functional Ankle Instability.

Sports Health 2021 Aug 16:19417381211035781. Epub 2021 Aug 16.

Department of Physical Therapy, College of Medicine, National Cheng Kung University, Tainan, Taiwan.

Background: Remodeled bicycle pedal training with multidirectional challenges through muscle strengthening and neuromuscular facilitation may increase dynamic postural control and performance during lateral shuffling for athletes with functional ankle instability (FAI).

Hypothesis: The 6-week remodeled bicycle pedal training is effective on the ankle joint control and muscle activation, and especially that of the ankle evertor muscle co-contraction to improve dynamic postural control during lateral shuffling for athletes with FAI.

Study Design: Laboratory randomized controlled trial. Read More

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The maternal pelvic floor and labor outcome.

Am J Obstet Gynecol MFM 2021 Aug 6:100452. Epub 2021 Aug 6.

Sydney Medical School Nepean, Department of O&G, University of Sydney, Penrith, New South Wales, Australia (Dr Dietz).

Vaginal birth is the major cause of pelvic floor damage. The development of transperineal ultrasound has improved our understanding of the relationship between vaginal birth and pelvic floor dysfunction. The female pelvic floor dimensions and function can be assessed reliably in pregnant women. Read More

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Effects of cane use on walking parameters and lower limb muscle activity in adults with spastic cerebral palsy: a cross-sectional study.

J Phys Ther Sci 2021 Jul 1;33(7):544-548. Epub 2021 Jul 1.

Department of Physical Therapy, Graduate School of Health Science, Sapporo Medical University, Japan.

[Purpose] Adults with cerebral palsy often use a cane as a walking aid because of their decreased gait ability. However, it is unclear whether this affects lower limb muscle activity during walking. The purpose of this study was to clarify the influence of using a cane during walking on the spatio-temporal parameters of walking, lower limb muscle activity, and lower limb muscle coactivation in adults with spastic cerebral palsy. Read More

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Characteristics of rectus femoris activation and rectus femoris-hamstrings coactivation during force-matching isometric knee extension in subacute stroke.

Exp Brain Res 2021 Aug 2;239(8):2621-2633. Epub 2021 Jul 2.

Center for Neuroscience and Neurological Recovery, Methodist Rehabilitation Center, 1350 East Woodrow Wilson Drive, Jackson, MS, 39216, USA.

The spectral properties of surface electromyographic (EMG) signal in the rectus femoris (RF) and the coactivation in the medial hamstrings (MH) were investigated in 45 stroke subjects (22 ± 12 days post-onset) and 30 age-matched healthy controls who performed unilateral knee extensions at maximum effort (100% MVC) and during 5-s force-matching tasks (10, 30, 50% MVC). The spectral properties were obtained through a power spectrum analysis based on Fast Fourier Transform. The coactivation was measured as the MH amplitude (%max) and MH/RF amplitude ratio. Read More

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A wearable electromyography-controlled functional electrical stimulation system improves balance, gait function, and symmetry in older adults.

Technol Health Care 2021 Jun 25. Epub 2021 Jun 25.

Department of Physical Therapy, Sahmyook University College of Health Science, Hwarang-ro, Nowon-gu, Seoul, Korea.

Background: Wearable technologies have been developed for healthy aging. The technology for electromyography (EMG)-controlled functional electrical stimulation (FES) systems has been developed, but research on how helpful it is in daily life has been insufficient.

Objective: The purpose of this study was to investigate the effect of the EMG-controlled FES system on muscle morphology, balance, and gait in older adults. Read More

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Anthropometrics and electromyography as predictors for maximal voluntary isometric wrist torque: Considerations for ergonomists.

Appl Ergon 2021 Nov 23;97:103496. Epub 2021 Jun 23.

Department of Kinesiology, Brock University, 1812 Sir Isaac Brock Way, St. Catharines, ON, Canada.

The purpose of this study was to evaluate anthropometry and forearm muscle activity as predictors of maximal isometric wrist torque. Thirteen anthropometric measures, forearm electromyography from flexor carpi radialis (FCR) and extensor carpi radialis (ECR), and maximal isometric wrist flexion/extension torque were obtained from 25 male participants. Pearson correlation coefficients assessed relationships between peak isometric torque and: (1) anthropometrics, (2) FCR and ECR activation, (3) FCR/ECR antagonist/agonist coactivation ratios. Read More

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November 2021

Hindlimb Somatosensory Information Influences Trunk Sensory and Motor Cortices to Support Trunk Stabilization.

Cereb Cortex 2021 Jun 24. Epub 2021 Jun 24.

Department of Biomedical Engineering, Science, and Health Systems, Drexel University, Philadelphia, 19104 PA, USA.

Sensorimotor integration in the trunk system is poorly understood despite its importance for functional recovery after neurological injury. To address this, a series of mapping studies were performed in the rat. First, the receptive fields (RFs) of cells recorded from thoracic dorsal root ganglia were identified. Read More

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Feedforward modulation of gamma motor neuron activity can improve motor command accuracy.

J Neural Eng 2021 05 28;18(4). Epub 2021 May 28.

Department of Clinical and Experimental Sciences, Università degli Studi di Brescia, Brescia, Italy.

. Coactivation of gamma and alpha motor neuron activity ensures that muscle spindle responsiveness is maintained during muscle contractions. However, some evidence suggests that the activity of gamma motor neurons is phase-advanced with respect to that of alpha motor neurons during manual control tasks. Read More

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Delayed and reduced intralimb muscular coupling during postural reactions in individuals with incomplete spinal cord injury.

Gait Posture 2021 07 8;88:84-93. Epub 2021 May 8.

School of Rehabilitation, Faculty of Medicine, Université de Montréal, Canada; Centre for Interdisciplinary Research in Rehabilitation of Greater Montréal (CRIR), Canada. Electronic address:

Background: Postural strategies are enabled by rapid muscle activation sequences to prevent a fall. Intralimb muscular couplings underlie these postural strategies are likely impaired after incomplete spinal cord injury (iSCI), leading to inappropriate postural reactions and increased fall risk; yet, the nature of these changes is unknown.

Research Question: Identify changes occurring in intralimb coupling following a perturbation in individuals with iSCI. Read More

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A New Definition of Poststroke Spasticity and the Interference of Spasticity With Motor Recovery From Acute to Chronic Stages.

Neurorehabil Neural Repair 2021 Jul 12;35(7):601-610. Epub 2021 May 12.

Shirley Ryan Ability Lab, Chicago, IL, USA.

The relationship of poststroke spasticity and motor recovery can be confusing. "True" motor recovery refers to return of motor behaviors to prestroke state with the same end-effectors and temporo-spatial pattern. This requires neural recovery and repair, and presumably occurs mainly in the acute and subacute stages. Read More

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Effects of bi-axial ankle strengthening on muscle co-contraction during gait in chronic stroke patients: A randomized controlled pilot study.

Gait Posture 2021 06 15;87:177-183. Epub 2021 Apr 15.

National Rehabilitation Research Institute, National Rehabilitation Center, Seoul, South Korea. Electronic address:

Introduction: Ankle dysfunction in patients with stroke is a common but serious cause of balance and gait impairments. However, comprehensive paretic ankle training seldom exists. Thus, we investigated the effects of a bi-axial ankle muscle training program using visual feedback as a means to improve ankle strength and performance of functional activities in patients with stroke. Read More

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Simultaneous Recording of Motor Evoked Potentials in Hand, Wrist and Arm Muscles to Assess Corticospinal Divergence.

Brain Topogr 2021 07 4;34(4):415-429. Epub 2021 May 4.

Department of Physical Therapy and Rehabilitation Science, Carver College of Medicine, University of Iowa, Iowa City, IA, USA.

The purpose of this study was to further develop methods to assess corticospinal divergence and muscle coupling using transcranial magnetic stimulation (TMS). Ten healthy right-handed adults participated (7 females, age 34.0 ± 12. Read More

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An examination of a potential organized motor unit firing rate and recruitment scheme of an antagonist muscle during isometric contractions.

J Neurophysiol 2021 06 28;125(6):2094-2106. Epub 2021 Apr 28.

Neuromechanics Laboratory, Department of Health, Sport and Exercise Sciences, University of Kansas, Lawrence, Kansas.

The primary purpose of the present study is to determine if an organized control scheme exists for the antagonist muscle during steady isometric torque. A secondary focus is to better understand how firing rates of the antagonist muscle change from a moderate- to higher-contraction intensity. Fourteen subjects performed two submaximal isometric trapezoid muscle actions of the forearm flexors that included a linearly increasing, steady force at both 40% and 70% maximum voluntary contraction, and linearly decreasing segments. Read More

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The influence of cervical spine rehabilitation on bioelectrical activity (sEMG) of cervical and masticatory system muscles.

PLoS One 2021 26;16(4):e0250746. Epub 2021 Apr 26.

Orthopaedic and Rehabilitation Department, Medical University of Warsaw, Warsaw, Poland.

Background: Coexistence of temporomandibular joint discomfort along with cervical spine disorders is quite common, and is associated with many limitations and adverse symptoms for the patient. Both diagnostics and treatment of these ailments are difficult, and in many cases, the effects of therapy are not satisfactory. This study assessed the impact of a 3-week neck-only rehabilitation programme without direct intervention in the craniofacial area on the bioelectric activity of both the cervical spine and muscles in the craniofacial area among patients with idiopathic neck pain who do not report TMJ pain. Read More

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Impacts of Rehabilitation Gait Training on Functional Outcomes after Tibial Nerve Transfer for Patients with Peroneal Nerve Injury: A Nonrandomized Controlled Trial.

Plast Reconstr Surg 2021 May;147(5):1202-1207

From the Department of Surgery, Division of Plastic Surgery, and the Department of Medicine, Division of Physical Medicine and Rehabilitation, University of Alberta.

Background: Although there was initial success using tibial nerve transfer to restore ankle dorsiflexion following peroneal nerve injury, results from later series were less promising. A potential reason is coactivation of the much stronger antagonistic muscles during gait. The purpose of this study was to test the hypothesis that gait training would improve functional performance following tibial nerve transfer. Read More

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Development of a Low-Cost, Modular Muscle-Computer Interface for At-Home Telerehabilitation for Chronic Stroke.

Sensors (Basel) 2021 Mar 5;21(5). Epub 2021 Mar 5.

Department of Biomedical Engineering, University of Southern California, Los Angeles, CA 900089, USA.

Stroke is a leading cause of long-term disability in the United States. Recent studies have shown that high doses of repeated task-specific practice can be effective at improving upper-limb function at the chronic stage. Providing at-home telerehabilitation services with therapist supervision may allow higher dose interventions targeted to this population. Read More

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The influence of resistance training on neuromuscular function in middle-aged and older adults: A systematic review and meta-analysis of randomised controlled trials.

Exp Gerontol 2021 07 24;149:111320. Epub 2021 Mar 24.

Department of Sport, Exercise and Rehabilitation, Northumbria University, Newcastle-Upon-Tyne, United Kingdom.

Background: Deterioration of neuromuscular function is a major mechanism of age-related strength loss. Resistance training (RT) improves muscle strength and mass. However, the effects of RT on neuromuscular adaptations in middle-aged and older adults are unclear. Read More

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Standing on unstable surface challenges postural control of tracking tasks and modulates neuromuscular adjustments specific to task complexity.

Sci Rep 2021 03 17;11(1):6122. Epub 2021 Mar 17.

Department of Training and Movement Sciences, Humboldt-Universität zu Berlin, Philippstr. 13, Haus 11, 10115, Berlin, Germany.

Understanding the modulations of motor control in the presence of perturbations in task conditions of varying complexity is a key element towards the design of effective perturbation-based balance exercise programs. In this study we investigated the effect of mechanical perturbations, induced by an unstable surface, on muscle activation and visuo-postural coupling, when actively tracking target motion cues of different complexity. Four postural tasks following a visual oscillating target of varying target complexity (periodic-sinusoidal vs. Read More

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Characteristics of the severely impaired hand in survivors of stroke with chronic impairments.

Top Stroke Rehabil 2021 Mar 3:1-11. Epub 2021 Mar 3.

Shirley Ryan AbilityLab, Arms + Hands Lab, Chicago, Illinios, USA.

: Diminished sensorimotor control of the hand is one of the most common outcomes following stroke. This hand impairment substantially impacts overall function and quality of life; standard therapy often results in limited improvement. Mechanisms of dysfunction of the severely impaired post-stroke hand are still incompletely understood, thereby impeding the development of new targeted treatments. Read More

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Efference copy in kinesthetic perception: a copy of what is it?

Mark L Latash

J Neurophysiol 2021 04 10;125(4):1079-1094. Epub 2021 Feb 10.

Department of Kinesiology, The Pennsylvania State University, University Park, Pennsylvania.

A number of notions in the fields of motor control and kinesthetic perception have been used without clear definitions. In this review, we consider definitions for efference copy, percept, and sense of effort based on recent studies within the physical approach, which assumes that the neural control of movement is based on principles of parametric control and involves defining time-varying profiles of spatial referent coordinates for the effectors. The apparent redundancy in both motor and perceptual processes is reconsidered based on the principle of abundance. Read More

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Coactivation pattern in leg muscles during treadmill walking in patients suffering from intermittent claudication.

Gait Posture 2021 02 14;84:245-253. Epub 2020 Dec 14.

Le Mans Université, Movement - Interactions - Performance, MIP, EA 4334, F-72000, Le Mans, France. Electronic address:

Background: In patients with peripheral arterial disease and presenting intermittent claudication (PAD-IC), the pain due to ischemia impacts gait parameters, particularly in cases of unilateral disease. Deterioration of gait parameters in a pathological context is frequently associated with increased coactivation (simultaneous activation of agonist and antagonist muscles around a joint).

Research Question: Does unilateral PAD-IC affect the coactivation pattern during walking? Does the coactivation pattern change with increasing pain intensity?

Method: We evaluated symptomatic and asymptomatic legs in 17 subjects with unilateral PAD-IC and 16 without PAD-IC (control group), during walking. Read More

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February 2021

Non-specific chronic low back pain elicits kinematic and neuromuscular changes in walking and gait termination.

Gait Posture 2021 02 28;84:238-244. Epub 2020 Dec 28.

University of Rome "Foro Italico", Piazza Lauro De Bosis 6, 00135 Rome, Italy.

Background: Chronic low back pain (CLBP) is associated with an increased trunk stiffness and muscle coactivation during walking. However, it is still unclear whether CLBP individuals are unable to control neuromechanically their upper body motion during a sudden termination of gait (GT), which involves a challenging balance transition from walking to standing.

Research Question: Does CLBP elicit neuromuscular and kinematic changes which are specific to walking and GT?. Read More

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February 2021

Core Strength Training Can Alter Neuromuscular and Biomechanical Risk Factors for Anterior Cruciate Ligament Injury.

Am J Sports Med 2021 01;49(1):183-192

Department of Mechanical Engineering, Sogang University, Mapo-gu, Seoul, Republic of Korea.

Background: Core stability is influential in the incidence of lower extremity injuries, including anterior cruciate ligament (ACL) injuries, but the effects of core strength training on the risk for ACL injury remain unclear.

Hypothesis: Core muscle strength training increases the knee flexion angle, hamstring to quadriceps (H:Q) coactivation ratio, and vastus medialis to vastus lateralis (VM:VL) muscle activation ratio, as well as decreases the hip adduction, knee valgus, and tibial internal rotation angles.

Study Design: Controlled laboratory study. Read More

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January 2021

Changes in jaw and neck muscle coactivation and coordination in patients with chronic painful TMD disk displacement with reduction during chewing.

Physiol Behav 2021 03 24;230:113267. Epub 2020 Nov 24.

Department of Ophthalmology, Otorhinolaryngology and Head and Neck Surgery School of Medicine of Ribeirão Preto, University of São Paulo - USP, Ribeirão Preto (SP), 14049-900, Brazil; Craniofacial Research Support Center, University of São Paulo - USP, Ribeirão Preto (SP), Brazil. Electronic address:

The treatment of a complex temporomandibular disorder (TMD), such as disk displacement with reduction (DDR) associated with arthralgia and myalgia, may depends on understanding the impairments in muscle function. The aim of this study was to investigate the behavior of the anterior temporalis, masseter and sternocleidomastoid muscles in the time and frequency domains during chewing in patients with chronic painful TMD-DDR using electromyographic (EMG) analysis. Thirty-three patients who met the diagnostic criteria for TMD and 32 volunteers without TMD (control group) underwent clinical examination, chewing pattern classification and EMG analysis. Read More

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Neuromuscular Strategies in Stretch-Shortening Exercises with Increasing Drop Heights: The Role of Muscle Coactivation in Leg Stiffness and Power Propulsion.

Int J Environ Res Public Health 2020 11 21;17(22). Epub 2020 Nov 21.

Department of Biotechnological and Applied Clinical Sciences, University of L'Aquila, 67100 L'Aquila, Italy.

When applying drop jump exercises, knowing the magnitude of the stimulus is fundamental to stabilize the leg joints and to generate movements with the highest power. The effects of different drop heights on leg muscles coactivation, leg stiffness and power propulsion were investigated in fifteen sport science students. Drop jumps from heights of 20, 30, 40, 50, and 60 cm in a random order were performed on a force platform. Read More

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November 2020

Effect of local and general fatiguing exercises on disturbed and static postural control.

J Electromyogr Kinesiol 2021 Feb 7;56:102487. Epub 2020 Nov 7.

Department of Sports Science, College of Education, Zhejiang University, Hangzhou 310058, China; Centre for Psychological Sciences, Zhejiang University, Hangzhou 310028, China. Electronic address:

This study compared the effect of local and general fatiguing exercise on disturbed and static postural control performances. Surface electromyography and center of pressure signals were respectively recorded during self-initiated perturbation test and static postural stability test from 7 young male subjects. Local fatiguing exercise was performed using intermittent isometric knee extensions at the level of 40% of maximal voluntary torques. Read More

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February 2021

An Appraisal of Electrodiagnostic Studies in Stiff Person Syndrome.

J Clin Neuromuscul Dis 2020 Dec;22(2):84-89

Neuromuscular Center, Department of Neurology, Neurological Institute, Cleveland Clinic, Cleveland, OH.

A literature review was performed on the use of electrodiagnostic (EDX) tests including nerve conduction study, electromyography, exteroceptive reflex, blink reflex, and late response in the evaluation of patients with stiff person syndrome (SPS). A web survey was conducted to report the extent of EDX testing usage in the evaluation of SPS among laboratories accredited by the American Academy of Neuromuscular and Electrodiagnostic Medicine. Coactivation of selected agonist and antagonist muscles was performed in 5 healthy subjects to determine its specificity for SPS. Read More

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December 2020

Muscle Eccentric Contractions Increase in Downhill and High-Grade Uphill Walking.

Front Bioeng Biotechnol 2020 14;8:573666. Epub 2020 Oct 14.

Department of Biomedical Engineering, University of Virginia, Charlottesville, VA, United States.

In Duchenne muscular dystrophy (DMD), one of the most severe and frequent genetic diseases in humans, dystrophic muscles are prone to damage caused by mechanical stresses during eccentric contractions. Eccentric contraction during walking on level ground likely contributes to the progression of degeneration in lower limb muscles. However, little is known about how the amount of muscle eccentric contractions is affected by uphill/downhill sloped walking, which is often encountered in patients' daily lives and poses different biomechanical demands than level walking. Read More

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October 2020

Compensatory Movement Patterns Are Based on Abnormal Activity of the Biceps Brachii and Posterior Deltoid Muscles in Patients with Symptomatic Rotator Cuff Tears.

Clin Orthop Relat Res 2021 Feb;479(2):378-388

E. J. D. Veen, K. H. M. Verdonschot, T. E. Sluijter, T. de Groot, R. L. Diercks, M. Stevens, Department of Orthopedics, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.

Background: Abnormal movement patterns due to compensatory mechanisms have been reported in patients with rotator cuff tears. The long head of the biceps tendon may especially be overactive and a source of pain and could induce abnormal muscle activation in these patients. It is still unknown why some patients with a rotator cuff tear develop complaints and others do not. Read More

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February 2021