1,381 results match your criteria Motor Unit Recruitment in EMG


Motor unit action potential amplitudes and firing rates during repetitive muscle actions of the first dorsal interosseous in children and adults.

Eur J Appl Physiol 2019 Feb 15. Epub 2019 Feb 15.

Neuromechanics Laboratory, Department of Health, Sport, and Exercise Sciences, University of Kansas, 1301 Sunnyside Ave, Room 101BE, Lawrence, KS, 66045, USA.

Purpose: Previous research has indicated greater muscle activation is needed for children (CH) to match relative intensity submaximal contractions in comparison with adults (AD). However, no study has compared motor unit (MU) firing and recruitment patterns between children and adults. Therefore, MU action potential amplitudes (MUAP) and firing rates were examined during two repetitive submaximal contractions of the first dorsal interosseous in children and adults. Read More

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http://dx.doi.org/10.1007/s00421-019-04090-0DOI Listing
February 2019

You are as fast as your motor neurons: Speed of recruitment and maximal discharge of motor neurons determine the maximal rate of force development in humans.

J Physiol 2019 Feb 15. Epub 2019 Feb 15.

Department of Bioengineering, Imperial College London, SW7 2AZ, London, UK.

Key Points: We propose and validate a method to accurately identify the activity of populations of motor neurons during contractions at maximal rate of force development in humans. The behaviour of the motor neuron pool during rapid voluntary contractions in humans is presented. We show with this approach that the motor neuron recruitment speed and maximal motor unit discharge rate largely explains the individual ability in generating rapid force contractions. Read More

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http://dx.doi.org/10.1113/JP277396DOI Listing
February 2019

Neuromuscular efficiency in fibromyalgia is improved by hyperbaric oxygen therapy: looking inside muscles by means of surface electromyography.

Clin Exp Rheumatol 2019 Jan-Feb;37 Suppl 116(1):75-80. Epub 2019 Feb 8.

NeuroMuscularFunction/Research Group, School of Exercise & Sport Sciences, Department of Medical Sciences, University of Turin, Italy.

Objectives: Neuromuscular efficiency (NME) is impaired in fibromyalgia (FM). Hyperbaric oxygen therapy (HBOT) is a medical treatment using 100% of oxygen through an oxygen mask. HBOT in FM induces changes in cortical excitability and a secondary reduction in pain and muscle fatigue. Read More

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February 2019
1 Read

The increase in muscle force after 4 weeks of strength training is mediated by adaptations in motor unit recruitment and rate coding.

J Physiol 2019 Feb 6. Epub 2019 Feb 6.

Department of Bioengineering, Imperial College London, London, UK.

Key Points: Previous studies have indicated that several weeks of strength training is sufficient to elicit significant adaptations in the neural drive sent to the muscles. There are few data, however, on the changes elicited by strength training in the recruitment and rate coding of motor units during voluntary contractions. We show for the first time that the discharge characteristics of motor units in the tibialis anterior muscle tracked across the intervention are changed by 4 weeks of strength training with isometric voluntary contractions. Read More

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http://dx.doi.org/10.1113/JP277250DOI Listing
February 2019

Anatomo-functional characterisation of the human "hand-knob": A direct electrophysiological study.

Cortex 2018 Dec 24;113:239-254. Epub 2018 Dec 24.

Laboratory of Motor Control, Department of Medical Biotechnologies and Translational Medicine, Università Degli Studi di Milano, Humanitas Research Hospital, IRCCS, Milano, Italy. Electronic address:

The cortical area within the human primary motor cortex (M1) that hosts the representation of the hand and fingers is known as the 'hand-knob' and is essential for voluntary hand movement. The anatomo-functional heterogeneity described within the monkey primary motor cortex (M1) in a rostro-caudal direction suggests an internal subdivision in two sectors originating different systems of connections to the spinal cord. Direct investigation of the human hand-knob has been prevented, so far, by methodological constraints. Read More

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https://linkinghub.elsevier.com/retrieve/pii/S00109452183043
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http://dx.doi.org/10.1016/j.cortex.2018.12.011DOI Listing
December 2018
2 Reads

Effect of Resistance Training and Fish Protein Intake on Motor Unit Firing Pattern and Motor Function of Elderly.

Front Physiol 2018 4;9:1733. Epub 2018 Dec 4.

Faculty of Sociology, Kyoto Sangyo University, Kyoto, Japan.

We investigated the effect of resistance training and fish protein intake on the motor unit firing pattern and motor function in elderly. Fifty healthy elderly males and females (69.2 ± 4. Read More

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http://dx.doi.org/10.3389/fphys.2018.01733DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6288440PMC
December 2018

Overground walking with a robotic exoskeleton elicits trunk muscle activity in people with high-thoracic motor-complete spinal cord injury.

J Neuroeng Rehabil 2018 Nov 20;15(1):109. Epub 2018 Nov 20.

School of Kinesiology, University of British Columbia, Vancouver, Canada.

Background: The trunk muscles are critical for postural control. Recent neurophysiological studies have revealed sparing of trunk muscle function in individuals with spinal cord injury (SCI) classified with thoracic or cervical motor-complete injuries. These findings raise the possibility for recruiting and retraining this spared trunk function through rehabilitation. Read More

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http://dx.doi.org/10.1186/s12984-018-0453-0DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6245830PMC
November 2018
11 Reads

Characterizing Residual Muscle Properties in Lower Limb Amputees Using High Density EMG Decomposition: A Pilot Study.

Conf Proc IEEE Eng Med Biol Soc 2018 Jul;2018:5974-5977

As research is progressing towards EMG control of lower limb prostheses, it is vital to understand the neurophysiology of the residual muscles in the amputated limb, which has been largely ignored. Therefore, the goal of this study was to characterize the activation patterns (muscle recruitment and motor unit discharge patterns) of the residual muscles of lower limb amputees. One transtibial amputee subject was recruited for this pilot study. Read More

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https://ieeexplore.ieee.org/document/8513661/
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http://dx.doi.org/10.1109/EMBC.2018.8513661DOI Listing
July 2018
8 Reads

Wavelet analyses of electromyographic signals derived from lower extremity muscles while walking or running: A systematic review.

PLoS One 2018 2;13(11):e0206549. Epub 2018 Nov 2.

Bern University of Applied Sciences, Department of Health Professions, Division of Physiotherapy, Bern, Switzerland.

Surface electromyography is often used to assess muscle activity and muscle function. A wavelet approach provides information about the intensity of muscle activity and motor unit recruitment strategies at every time point of the gait cycle. The aim was to review papers that employed wavelet analyses to investigate electromyograms of lower extremity muscles during walking and running. Read More

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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0206549PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6214539PMC
November 2018
2 Reads

Stroke increases ischemia-related decreases in motor unit discharge rates.

J Neurophysiol 2018 Dec 31;120(6):3246-3256. Epub 2018 Oct 31.

Department of Physical Therapy, Marquette University , Milwaukee, Wisconsin.

Following stroke, hyperexcitable sensory pathways, such as the group III/IV afferents that are sensitive to ischemia, may inhibit paretic motor neurons during exercise. We quantified the effects of whole leg ischemia on paretic vastus lateralis motor unit firing rates during submaximal isometric contractions. Ten chronic stroke survivors (>1 yr poststroke) and 10 controls participated. Read More

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http://dx.doi.org/10.1152/jn.00923.2017DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6337044PMC
December 2018
1 Read

Muscle Biopsy and Electromyography Correlation.

Front Neurol 2018 9;9:839. Epub 2018 Oct 9.

Department of Neurology, Mayo Clinic, Rochester, MN, United States.

In myopathies, the correlation of individual electromyographic and histopathologic findings remains poorly explored, as most previous studies have focused on the ability of muscle biopsy and electromyography to distinguish the neuropathic vs. myopathic nature of the underlying neuromuscular disease. We identified 100 patients who had a muscle biopsy and electromyography performed on identical muscles. Read More

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http://dx.doi.org/10.3389/fneur.2018.00839DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6189315PMC
October 2018
1 Read

The influence of input excitation on the inter- and intra-day reliability of the motor unit firing rate versus recruitment threshold relationship.

J Neurophysiol 2018 Dec 24;120(6):3131-3139. Epub 2018 Oct 24.

Applied Neuromuscular Physiology Laboratory, Oklahoma State University , Stillwater, Oklahoma.

Decomposition of the surface electromyographic (sEMG) signal is commonly used to examine motor unit (MU) firing behavior. However, the intra- and inter-day reliability of these measurements has yet to be quantified or reported. This investigation 1) examined the effect of input excitation on the mean firing rate (MFR) vs. Read More

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http://dx.doi.org/10.1152/jn.00490.2018DOI Listing
December 2018

Nerve Transfers for Enterovirus D68-Associated Acute Flaccid Myelitis: A Case Series.

Pediatr Neurol 2018 Nov 20;88:25-30. Epub 2018 Aug 20.

Center for Brachial Plexus and Traumatic Nerve Injury, Hospital for Special Surgery, New York, New York; Weill Medical College of Cornell University, New York, New York; New York-Presbyterian Hospital, New York, New York. Electronic address:

Background: Acute flaccid myelitis is associated with enterovirus D68 -induced inflammation and destruction of cervical anterior horn cells. To date, no medical intervention has altered the disease course.

Methods: We report two pediatric patients who were treated with nerve transfer in three limbs with sustained upper extremity neuropathy. Read More

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https://linkinghub.elsevier.com/retrieve/pii/S08878994173113
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http://dx.doi.org/10.1016/j.pediatrneurol.2018.07.018DOI Listing
November 2018
5 Reads

Corticospinal excitability during shortening and lengthening actions with incremental torque output.

Exp Physiol 2018 Dec 16;103(12):1586-1592. Epub 2018 Oct 16.

Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, United Kingdom.

New Findings: What is the central question of this study? The relationship between motor unit recruitment and firing rate has been related to the size of the corticospinal output with variations in the nervous system gain during isometric contractions. However, corticospinal behaviour with incremental torque output might differ during anisometric contractions owing to differences in neural control of anisometric contraction types. What is the main finding and its importance? Corticospinal excitability during lengthening contractions was smaller compared with shortening but increased with incremental torque output in a similar manner between contraction types. Read More

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http://dx.doi.org/10.1113/EP087347DOI Listing
December 2018
10 Reads

Degraded Synergistic Recruitment of sEMG Oscillations for Cerebral Palsy Infants Crawling.

Front Neurol 2018 18;9:760. Epub 2018 Sep 18.

Key Laboratory of Biorheological Science and Technology of Ministry of Education, Chongqing University, Chongqing, China.

Synergistic recruitment of muscular activities is a generally accepted mechanism for motor function control, and motor dysfunction, such as cerebral palsy (CP), destroyed the synergistic electromyography activities of muscle group for limb movement. However, very little is known how motor dysfunction of CP affects the organization of the myoelectric frequency components due to the abnormal motor unit recruiting patterns. Exploring whether the myoelectric activity can be represented with synergistic recruitment of surface electromyography (sEMG) frequency components; evaluating the effect of CP motor dysfunction on the synergistic recruitment of sEMG oscillations. Read More

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https://www.frontiersin.org/article/10.3389/fneur.2018.00760
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http://dx.doi.org/10.3389/fneur.2018.00760DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6153367PMC
September 2018
14 Reads

Genetic variant in the β -adrenergic receptor (Arg16Gly) influences fat-free mass, muscle strength and motor unit behaviour in young men.

Exp Physiol 2018 Dec 1;103(12):1645-1655. Epub 2018 Nov 1.

Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada.

New Findings: What is the central question of this study? Does a common genetic variant in the β -adrenergic receptor (β -AR) have effects on skeletal muscle function in young, healthy men? What is the main finding and its importance? This study provides preliminary evidence that β -AR Arg16Gly genotype has a significant effect on fat-free mass, muscle strength and motor unit behaviour in recreationally trained men. These data might have important clinical and exercise-related implications. For example, β -AR (rs1042713) genotype might influence the responsiveness of skeletal muscle to clinical or exercise-based interventions or β-AR agonist treatment. Read More

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http://dx.doi.org/10.1113/EP087145DOI Listing
December 2018
2 Reads

Bilateral sciatic neuropathy with severe rhabdomyolysis following venlafaxine overdose: A case report.

Medicine (Baltimore) 2018 Sep;97(37):e12220

Department of Rehabilitation Medicine, Daegu Fatima Hospital, Daegu, Republic of Korea.

Rationale: Venlafaxine is an antidepressant and anxiolytic agent that functions by inhibiting central serotonin and norepinephrine reuptake, and it is a relatively recently introduced drug. In particular, overdose of venlafaxine has been reported to cause severe cardiac toxicity including ventricular tachycardia, prolongation of QT interval, and seizure or severe muscular injury. However, reports describing venlafaxine-induced rhabdomyolysis with neuropathy remain scarce. Read More

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http://dx.doi.org/10.1097/MD.0000000000012220DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6155956PMC
September 2018
4 Reads

Effect of reflexive activation of motor units on torque development during electrically-evoked contractions of the triceps surae muscle.

J Appl Physiol (1985) 2019 Feb 13;126(2):386-392. Epub 2018 Sep 13.

INSERM UMR1093-CAPS, Université Bourgogne Franche-Comté, UFR des Sciences du Sport, Dijon , France.

The aim of the study was to identify stimulation conditions permitting the occurrence of extra torque (ET) and to examine their impact on spinal and corticospinal excitabilities. Twelve subjects received stimulation trains over the tibial nerve (20 s duration, 1 ms pulse duration) that were delivered at 3 stimulation frequencies (20, 50, and 100 Hz) and at 5 intensities (110%, 120%, 130%, 140%, and 150% of the motor threshold). Torque-time integral (TTI) of each stimulation train was calculated. Read More

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http://dx.doi.org/10.1152/japplphysiol.00463.2018DOI Listing
February 2019
2 Reads

Does vibration superimposed on low-level isometric contraction alter motor unit recruitment strategy?

J Neural Eng 2018 Dec 22;15(6):066001. Epub 2018 Aug 22.

Faculty of Electrical Engineering, Eindhoven University of Technology, Eindhoven, Netherlands.

Objective: Beneficial effects, including improved muscle strength and power performance, have been observed during vibration exercise (VE) and partially ascribed to a specific reflex mechanism referred to as Tonic vibration reflex (TVR). TVR involves motor unit (MU) activation synchronized and un-synchronized with the vibration cycle; this suggests VE to alter the temporal MU recruitment strategy. However, the effects of VE on MU recruitment remain poorly understood. Read More

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http://stacks.iop.org/1741-2552/15/i=6/a=066001?key=crossref
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http://dx.doi.org/10.1088/1741-2552/aadc43DOI Listing
December 2018
5 Reads

Reorganization of motor unit activity at different sites within the human masseter muscle during experimental masseter pain.

Eur J Oral Sci 2018 10 30;126(5):400-410. Epub 2018 Jul 30.

Jaw Function and Orofacial Pain Research Unit, Faculty of Dentistry, Westmead Hospital Centre for Oral Health, University of Sydney, Westmead, Australia.

The aims were to test the hypotheses that experimental masseter muscle pain leads to recruitment and/or derecruitment of motor units at different sites within the masseter and that the patterns of change in motor unit activity differ between sites. Single motor unit (SMU) activity was recorded at two sites within the right masseter [superior/anterior, inferior/posterior (IP)] during isometric biting tasks (ramp, step level) on an intraoral force transducer in 17 participants during three experimental blocks comprising no infusion (baseline), 5% hypertonic saline infusion (pain), or isotonic saline infusion (control). A visual analog scale (VAS) was used to score pain intensity. Read More

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http://dx.doi.org/10.1111/eos.12561DOI Listing
October 2018
8 Reads

Higher muscle fiber conduction velocity and early rate of torque development in chronically strength trained individuals.

J Appl Physiol (1985) 2018 07 19. Epub 2018 Jul 19.

Università di Roma Foro Italico, Italy.

Strength trained individuals (ST) develop greater levels of force when compared to untrained subjects. These differences are partly of neural origin and can be explained by training induced changes in the neural drive to the muscles. In the present study we hypothesize a greater rate of torque development (RTD) and faster recruitment of motor units with greater muscle fiber conduction velocity (MFCV) in ST when compared to a control cohort. Read More

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http://dx.doi.org/10.1152/japplphysiol.00025.2018DOI Listing

Validity of Wearable Electromyographical Compression Shorts to Predict Lactate Threshold During Incremental Exercise in Healthy Participants.

J Strength Cond Res 2018 Jul 2. Epub 2018 Jul 2.

Department of Kinesiology, The University of Alabama, Tuscaloosa, Alabama.

Snarr, RL, Tolusso, DV, Hallmark, AV, and Esco, MR. Validity of wearable electromyographical compression shorts to predict lactate threshold during incremental exercise in healthy participants. J Strength Cond Res XX(X): 000-000, 2018-Determination of lactate threshold (LT) is an important variable in improving cardiovascular endurance and performance. Read More

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http://dx.doi.org/10.1519/JSC.0000000000002721DOI Listing
July 2018
3 Reads

Examination of muscle morphology and neuromuscular function in normal weight and overfat children aged 7-10 years.

Scand J Med Sci Sports 2018 Nov 26;28(11):2310-2321. Epub 2018 Jul 26.

Department of Nutrition, Health and Human Performance, Meredith College, Raleigh, North Carolina.

Neuromuscular function in young overweight/obese (OF) children is not well described.

Aim: This study examined isometric and isokinetic leg extensor strength, muscle size (mCSA) and tissue composition as measured via echo intensity (mEI), and motor unit (MU) firing rates in normal weight (NW) and OF children aged 7-10 years.

Methods: Fourteen NW (eight girls and six boys, BMI: 15. Read More

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http://dx.doi.org/10.1111/sms.13256DOI Listing
November 2018
1 Read

Acute whole-body vibration increases reciprocal inhibition.

Hum Mov Sci 2018 Aug 26;60:191-201. Epub 2018 Jun 26.

Department of Sports and Sports Science, University of Freiburg, Schwarzwaldstraße 175, 79117 Freiburg, Germany.

Based on previous evidence that whole-body vibration (WBV) affects pathways involved in disynaptic reciprocal inhibition (DRI), the present hypothesis-driven experiment aimed to assess the acute effects of WBV on DRI and co-contraction. DRI from ankle dorsiflexors to plantar flexors was investigated during submaximal dorsiflexion before and after 1 min of WBV. With electromyography, musculus soleus (SOL) H-reflex depression following a conditioning stimulation of the peroneal nerve (1. Read More

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https://linkinghub.elsevier.com/retrieve/pii/S01679457173066
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http://dx.doi.org/10.1016/j.humov.2018.06.011DOI Listing
August 2018
5 Reads

Sub-threshold depolarizing pre-pulses can enhance the efficiency of biphasic stimuli in transcutaneous neuromuscular electrical stimulation.

Med Biol Eng Comput 2018 Dec 9;56(12):2213-2219. Epub 2018 Jun 9.

Tecnologico de Monterrey, Escuela de Ingeniería y Ciencias, Ave. Eugenio Garza Sada 2501 Sur, 64849, Monterrey, Mexico.

There is multiple evidence in the literature that a sub-threshold pre-pulse, delivered immediately prior to an electrical stimulation pulse, can alter the activation threshold of nerve fibers and motor unit recruitment characteristics. So far, previously published works combined monophasic stimuli with sub-threshold depolarizing pre-pulses (DPPs) with inconsistent findings-in some studies, the DPPs decreased the activation threshold, while in others it was increased. This work aimed to evaluate the effect of DPPs during biphasic transcutaneous electrical stimulation and to study the possible mechanism underlying those differences. Read More

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http://dx.doi.org/10.1007/s11517-018-1851-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6245015PMC
December 2018
4 Reads

Vastus lateralis muscle tissue composition and motor unit properties in chronically endurance-trained vs. sedentary women.

Eur J Appl Physiol 2018 Sep 11;118(9):1789-1800. Epub 2018 Jun 11.

Neuromechanics Laboratory, Department of Health, Sport, and Exercise Sciences, University of Kansas, 1301 Sunnyside Ave, Room 101BE, Lawrence, KS, 66045, USA.

This study examined motor unit (MU) amplitudes (AP) and firing rates during moderate-intensity contractions and muscle cross-sectional area (mCSA) and echo intensity (mEI) of the vastus lateralis (VL) in chronically endurance-trained and sedentary females. Eight endurance-trained (ET) and nine sedentary controls (SED) volunteered for this study. Surface electromyographic (EMG) signals from a five-pin electrode array were recorded from the VL during isometric trapezoid muscle actions at 40% of maximal voluntary contraction (MVC). Read More

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http://dx.doi.org/10.1007/s00421-018-3909-9DOI Listing
September 2018
7 Reads

Energy cost and lower leg muscle activities during erect bipedal locomotion under hyperoxia.

J Physiol Anthropol 2018 Jun 19;37(1):18. Epub 2018 Jun 19.

Division of Human Environmental Science, Mt. Fuji Research Institute, 5597-1 Kamiyoshida, Fujiyoshida-shi, Yamanashi, 403-0005, Japan.

Background: Energy cost of transport per unit distance (CoT) against speed shows U-shaped fashion in walking and linear fashion in running, indicating that there exists a specific walking speed minimizing the CoT, being defined as economical speed (ES). Another specific gait speed is the intersection speed between both fashions, being called energetically optimal transition speed (EOTS). We measured the ES, EOTS, and muscle activities during walking and running at the EOTS under hyperoxia (40% fraction of inspired oxygen) on the level and uphill gradients (+ 5%). Read More

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http://dx.doi.org/10.1186/s40101-018-0177-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6006575PMC
June 2018
12 Reads

Voluntary muscle activation and evoked volitional-wave responses as a function of torque.

J Electromyogr Kinesiol 2018 Aug 22;41:1-8. Epub 2018 Apr 22.

The Department of Health and Exercise Science, The University of Oklahoma, Norman, OK, United States.

Introduction: This study employed a unique stimulation paradigm which allowed for the simultaneous assessment of voluntary activation levels (VA) via twitch-interpolation, and the evoked V-wave responses of the plantar flexors during submaximal and maximal contractions. Test-retest reliability was also examined.

Methods: Fourteen participants repeated a stimulation protocol over four visits to assess VA and evoked V-wave amplitude across torque levels ranging from 20% to 100% MVC. Read More

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http://dx.doi.org/10.1016/j.jelekin.2018.04.002DOI Listing
August 2018
2 Reads

Variability of estimates of muscle fiber conduction velocity and surface EMG amplitude across subjects and processing intervals.

J Electromyogr Kinesiol 2018 Jun 24;40:102-109. Epub 2018 Apr 24.

Department of Movement, Human and Health Sciences, University of Rome "Foro Italico", 00135 Rome, Italy.

The force developed by the human neuromuscular system can change very rapidly (15-50 ms). When processing EMG signals for inferring neural control strategies, it is therefore necessary to extract estimates from short time intervals. In this study, we investigate the relation between joint torque and estimates of average muscle fibre conduction velocity (MFCV) and amplitude (RMS) from surface EMG signals, when varying the duration of the processing interval. Read More

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http://dx.doi.org/10.1016/j.jelekin.2018.04.010DOI Listing
June 2018
2 Reads

Higher torque and muscle fibre conduction velocity of the Biceps Brachii in karate practitioners during isokinetic contractions.

J Electromyogr Kinesiol 2018 Jun 17;40:81-87. Epub 2018 Apr 17.

University of Rome "Foro Italico", Department of Human, Movement and Health Science, Italy.

Purpose: Although upper limb techniques are largely utilized during karate combat competitions scarce information regarding their NM control is available. This study aims at investigating the effect of karate practice on the NM control of Biceps and Triceps Brachii during isokinetic contractions to enhance current knowledge on neuromuscular control adaptations and training methodologies in combat sports.

Methods: Torque and surface electromyograms (sEMG) of Biceps Brachii Caput Longum (BB) and Triceps Brachii Lateral Head (TB) were recorded in eight karate practitioners (KA) and eight age-matched sedentary individuals (CO) during isokinetic elbow flexion-extensions (0-240°/s). Read More

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http://dx.doi.org/10.1016/j.jelekin.2018.04.005DOI Listing
June 2018
3 Reads

Electromyographic Findings After Epidural Steroid Injections in Patients with Radicular Low Back Pain: A Prospective Open-Label Study.

Anesth Pain Med 2017 Dec 27;7(6):e62556. Epub 2017 Dec 27.

2nd Department of Anesthesiology, School of Medicine, National and Kapodistrian University of Athens, "Attikon" Hospital, Athens, Greece.

Epidural steroid injections (ESIs) are commonly used in the management of chronic lower back and leg pain. The aim of this study was to investigate the short- and long-term electromyographic and clinical outcome of patients with chronic radicular pain after ESIs. This prospective, open-label study, included patients with chronic radicular pain due to disc herniation or spinal stenosis, who underwent interlaminar, fluoroscopy-guided ESIs. Read More

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http://dx.doi.org/10.5812/aapm.62556DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5903381PMC
December 2017
8 Reads

High-threshold motor unit firing reflects force recovery following a bout of damaging eccentric exercise.

PLoS One 2018 9;13(4):e0195051. Epub 2018 Apr 9.

Faculty of Health Sciences and Sport, University of Stirling, Stirling, Scotland.

Exercise-induced muscle damage (EIMD) is associated with impaired muscle function and reduced neuromuscular recruitment. However, motor unit firing behaviour throughout the recovery period is unclear. EIMD impairment of maximal voluntary force (MVC) will, in part, be caused by reduced high-threshold motor unit firing, which will subsequently increase to recover MVC. Read More

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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0195051PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5890972PMC
July 2018
2 Reads

Trunk muscle recruitment patterns in simulated precrash events.

Traffic Inj Prev 2018 02;19(sup1):S186-S188

a Department of Mechanics and Maritime Sciences , Chalmers University of Technology , Gothenburg , Sweden.

Objectives: To quantify trunk muscle activation levels during whole body accelerations that simulate precrash events in multiple directions and to identify recruitment patterns for the development of active human body models.

Methods: Four subjects (1 female, 3 males) were accelerated at 0.55 g (net Δv = 4. Read More

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http://dx.doi.org/10.1080/15389588.2018.1426917DOI Listing
February 2018

Contralateral effect of short-duration unilateral neuromuscular electrical stimulation and focal vibration in healthy subjects.

Eur J Phys Rehabil Med 2018 Dec 12;54(6):911-920. Epub 2018 Mar 12.

Physical and Rehabilitation Medicine, Department of Medical Oral and Biotechnological Sciences, Gabriele d'Annunzio University, Chieti, Italy.

Background: The "contralateral effect" phenomenon refers to the strength gain in the opposite, untrained homonymous muscle following unilateral training. Previous studies showed that neuromuscular electrical stimulation (NMES) of the right quadriceps facilitated maximal voluntary strength and efferent neural drive of the left knee extensors, while no previous study investigated the contralateral effect elicited by focal muscle vibration.

Aim: The aim of this study was to investigate whether quadriceps NMES and focal vibration, when applied unilaterally, have the same potential to enhance the contralateral muscle strength and the associated neural drive. Read More

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http://dx.doi.org/10.23736/S1973-9087.18.05004-9DOI Listing
December 2018
8 Reads

Muscle phenotype is related to motor unit behavior of the vastus lateralis during maximal isometric contractions.

Physiol Rep 2018 03;6(5)

Applied Neuromuscular Physiology Laboratory, Oklahoma State University, Stillwater, Oklahoma.

Previous investigations have reported a relationship between skeletal muscle phenotype and motor unit (MU) firing parameters during submaximal contractions. The purpose of the current investigation, however, was to examine the relationships between motor unit firing behavior during a maximal voluntary contraction, Myosin Heavy Chain (MHC) isoform content, and various molecular neuromuscular targets of the vastus lateralis (VL) muscle in resistance-trained men. Ten resistance-trained males completed a trapezoidal ramp contraction up to 100% of their maximal voluntary isometric strength (MVIC). Read More

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http://dx.doi.org/10.14814/phy2.13636DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5845862PMC
March 2018
9 Reads

Hot Water Bathing Impairs Training Adaptation in Elite Teen Archers.

Chin J Physiol 2018 Apr;61(2):118-123

Department of Sports Sciences, University of Taipei, Taipei 11153, ROC.

Despite heat imposes considerable physiological stress to human body, hot water immersion remains as a popular relaxation modality for athletes. Here we examined the lingering effect of hot tub relaxation after training on performance-associated measures and dehydroepiandrosterone sulfate (DHEA-S) in junior archers. Ten national level archers, aged 16. Read More

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http://dx.doi.org/10.4077/CJP.2018.BAG560DOI Listing
April 2018
2 Reads
1.275 Impact Factor

Broca's Area as a Pre-articulatory Phonetic Encoder: Gating the Motor Program.

Front Hum Neurosci 2018 22;12:64. Epub 2018 Feb 22.

Laboratory of Motor Control, Department of Medical Biotechnology and Translational Medicine, University of Milan, Humanitas Research Hospital, IRCCS, Milan, Italy.

The exact nature of the role of Broca's area in control of speech and whether it is exerted at the cognitive or at the motor level is still debated. Intraoperative evidence of a lack of motor responses to direct electrical stimulation (DES) of Broca's area and the observation that its stimulation induces a "speech arrest" without an apparent effect on the ongoing activity of phono-articulatory muscles, raises the argument. Essentially, attribution of direct involvement of Broca's area in motor control of speech, requires evidence of a functional connection of this area with the phono-articulatory muscles' motoneurons. Read More

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http://dx.doi.org/10.3389/fnhum.2018.00064DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5826965PMC
February 2018
5 Reads

Altered trunk muscle recruitment patterns during lifting in individuals in remission from recurrent low back pain.

J Electromyogr Kinesiol 2018 Apr 21;39:128-133. Epub 2018 Feb 21.

Department of Rehabilitation, Faculty of Health Science and Technology, Kawasaki University of Medical Welfare, 288, Matsushima, Kurashiki City 701-0193, Japan.

Changes in the recruitment pattern of trunk muscles may contribute to the development of recurrent or chronic symptoms in people with low back pain (LBP). However, the recruitment pattern of trunk muscles during lifting tasks associated with a high risk of LBP has not been clearly determined in recurrent LBP. The present study aimed to investigate potential differences in trunk muscles recruitment patterns between individuals with recurrent LBP and asymptomatic individuals during lifting. Read More

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http://dx.doi.org/10.1016/j.jelekin.2018.02.008DOI Listing
April 2018
8 Reads

Differences in the motor unit firing rates and amplitudes in relation to recruitment thresholds during submaximal contractions of the first dorsal interosseous between chronically resistance-trained and physically active men.

Appl Physiol Nutr Metab 2018 Aug 26;43(8):759-768. Epub 2018 Feb 26.

a Neuromechanics Laboratory, Department of Health, Sport and Exercise Sciences, University of Kansas, Lawrence, KS 66045, USA.

Previous investigations report no changes in motor unit (MU) firing rates during submaximal contractions following resistance training. These investigations did not account for MU recruitment or examine firing rates as a function of recruitment threshold (REC). Therefore, MU recruitment and firing rates in chronically resistance-trained (RT) and physically active controls (CON) were examined. Read More

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http://dx.doi.org/10.1139/apnm-2017-0646DOI Listing
August 2018
3 Reads

Neurophysiological adaptations in the untrained side in conjunction with cross-education of muscle strength: a systematic review and meta-analysis.

J Appl Physiol (1985) 2018 Jun 15;124(6):1502-1518. Epub 2018 Feb 15.

Department of Biomedical Sciences, University of Sassari , Sassari , Italy.

We reviewed the evidence from randomized controlled trials (RCTs) focusing on the neurophysiological adaptations in the untrained side associated with cross-education of strength (CE) and pooled data into definite effect estimates for neurophysiological variables assessed in chronic CE studies. Furthermore, scoping directions for future research were provided to enhance the homogeneity and comparability of studies investigating the neural responses to CE. The magnitude of CE was 21. Read More

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http://dx.doi.org/10.1152/japplphysiol.01016.2017DOI Listing
June 2018
2 Reads

Motor Unit Action Potential Clustering-Theoretical Consideration for Muscle Activation during a Motor Task.

Front Hum Neurosci 2018 31;12:15. Epub 2018 Jan 31.

Faculty of Kinesiology, University of Calgary, Calgary, AB, Canada.

During dynamic or sustained isometric contractions, bursts of muscle activity appear in the electromyography (EMG) signal. Theoretically, these bursts of activity likely occur because motor units are constrained to fire temporally close to one another and thus the impulses are "clustered" with short delays to elicit bursts of muscle activity. The purpose of this study was to investigate whether a sequence comprised of "clustered" motor unit action potentials (MUAP) can explain spectral and amplitude changes of the EMG during a simulated motor task. Read More

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http://journal.frontiersin.org/article/10.3389/fnhum.2018.00
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http://dx.doi.org/10.3389/fnhum.2018.00015DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5797735PMC
January 2018
9 Reads

Vastus Lateralis Motor Unit Firing Rate Is Higher in Women With Patellofemoral Pain.

Arch Phys Med Rehabil 2018 05 10;99(5):907-913. Epub 2018 Feb 10.

Department of Physical Therapy, University of British Columbia, Vancouver, BC, Canada; Faculty of Health Sciences, Western University, London, ON, Canada. Electronic address:

Objective: To compare neural drive, determined from motor unit firing rate, in the vastus medialis and lateralis in women with and without patellofemoral pain.

Design: Cross-sectional study.

Setting: University research laboratory. Read More

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http://dx.doi.org/10.1016/j.apmr.2018.01.019DOI Listing
May 2018
7 Reads

Surface electromyographic amplitude does not identify differences in neural drive to synergistic muscles.

J Appl Physiol (1985) 2018 Apr 8;124(4):1071-1079. Epub 2018 Feb 8.

Department of Bioengineering, Imperial College London, Royal School of Mines , London , United Kingdom.

Surface electromyographic (EMG) signal amplitude is typically used to compare the neural drive to muscles. We experimentally investigated this association by studying the motor unit (MU) behavior and action potentials in the vastus medialis (VM) and vastus lateralis (VL) muscles. Eighteen participants performed isometric knee extensions at four target torques [10, 30, 50, and 70% of the maximum torque (MVC)] while high-density EMG signals were recorded from the VM and VL. Read More

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http://dx.doi.org/10.1152/japplphysiol.01115.2017DOI Listing
April 2018
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Hip position and sex differences in motor unit firing patterns of the vastus medialis and vastus medialis oblique in healthy individuals.

J Appl Physiol (1985) 2018 Jun 8;124(6):1438-1446. Epub 2018 Feb 8.

Department of Kinesiology, University of Texas at Austin , Austin, Texas.

Weakness of the vastus medialis oblique (VMO) has been proposed to explain the high prevalence of knee pain in female subjects. Clinicians commonly use exercises in an attempt to preferentially activate the VMO. Recently, our group found evidence to support clinical theory that the VMO is neurologically distinct from the vastus medialis (VM). Read More

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http://dx.doi.org/10.1152/japplphysiol.00702.2017DOI Listing
June 2018
3 Reads

Ischemic conditioning increases strength and volitional activation of paretic muscle in chronic stroke: a pilot study.

J Appl Physiol (1985) 2018 May 8;124(5):1140-1147. Epub 2018 Feb 8.

Department of Physical Medicine and Rehabilitation, Medical College of Wisconsin , Milwaukee, Wisconsin.

Ischemic conditioning (IC) on the arm or leg has emerged as an intervention to improve strength and performance in healthy populations, but the effects on neurological populations are unknown. The purpose of this study was to quantify the effects of a single session of IC on knee extensor strength and muscle activation in chronic stroke survivors. Maximal knee extensor torque measurements and surface EMG were quantified in 10 chronic stroke survivors (>1 yr poststroke) with hemiparesis before and after a single session of IC or sham on the paretic leg. Read More

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http://dx.doi.org/10.1152/japplphysiol.01072.2017DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6050199PMC
May 2018
4 Reads

The utility of motor unit number estimation methods versus quantitative motor unit potential analysis in diagnosis of ALS.

Clin Neurophysiol 2018 03 17;129(3):646-653. Epub 2018 Jan 17.

Department of Clinical Neurophysiology, Aarhus University Hospital, Aarhus, Denmark. Electronic address:

Objective: To compare the diagnostic utility of motor unit number estimation (MUNE) methods to motor unit potential (MUP) analysis in amyotrophic lateral sclerosis (ALS).

Methods: Twenty-five patients (1 definite, 11 probable, 9 possible ALS and 4 progressive muscular atrophy) and 22 healthy controls were prospectively included. Quantitative MUP analysis and three MUNE methods; Multiple Point Stimulation MUNE (MPS), Motor Unit Number Index (MUNIX) and MScanFit MUNE (MScan) were done in abductor pollicis brevis muscle. Read More

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http://dx.doi.org/10.1016/j.clinph.2018.01.002DOI Listing
March 2018
4 Reads

Examination of muscle composition and motor unit behavior of the first dorsal interosseous of normal and overweight children.

J Neurophysiol 2018 May 7;119(5):1902-1911. Epub 2018 Feb 7.

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

We examined differences between normal weight (NW) and overweight (OW) children aged 8-10 yr in strength, muscle composition, and motor unit (MU) behavior of the first dorsal interosseous. Ultrasonography was used to determine muscle cross-sectional area (CSA), subcutaneous fat (sFAT), and echo intensity (EI). MU behavior was assessed during isometric muscle actions at 20% and 50% of maximal voluntary contraction (MVC) by analyzing electromyography amplitude (EMG) and relationships between mean firing rates (MFR), recruitment thresholds (RT), and MU action potential amplitudes (MUAP) and durations (MUAP). Read More

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http://dx.doi.org/10.1152/jn.00675.2017DOI Listing
May 2018
2 Reads

Lateralized asymmetries in distribution of muscular evoked responses: An evidence of specialized motor control over an intrinsic hand muscle.

Brain Res 2018 04 3;1684:60-66. Epub 2018 Feb 3.

Departamento de Física, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo. Av. Bandeirantes, 3900, CEP: 14040-901, Monte Alegre, Ribeirão Preto, SP, Brazil; Departamento de Biociências e Atividades Físicas, Escola de Educação Física e Desportos, Universidade Federal do Rio de Janeiro. Av. Carlos Chagas Filho, 540, CEP: 21941-599, Cidade Universitária, Rio de Janeiro, RJ, Brazil; Laboratório de Neurobiologia II, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro. Av. Carlos Chagas Filho, 373, CEP: 21941-902, Cidade Universitária, Rio de Janeiro, RJ, Brazil. Electronic address:

Lateralized neural control over hand muscles has been associated with anatomical and physiological asymmetries in the central nervous system. Some studies suggested that the dominant cerebral hemisphere exhibit larger cortical representation areas with lower excitability, while others reported higher cortical excitability in dominant side compared to the contralateral, or even could not find any differences. Thus, neurophysiological lateral asymmetries are still controversial. Read More

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http://dx.doi.org/10.1016/j.brainres.2018.01.031DOI Listing
April 2018
2 Reads

Innervation status in chronic vocal fold paralysis and implications for laryngeal reinnervation.

Laryngoscope 2018 Jul 22;128(7):1628-1633. Epub 2018 Jan 22.

the University of Pittsburgh Voice Center, Division of Laryngology, Department of Otolaryngology, University of Pittsburgh School of Medicine, University of Pittsburgh.

Objective: Treatment options for symptomatic unilateral vocal fold paralysis (VFP) include vocal fold augmentation, laryngeal framework surgery, and laryngeal reinnervation. Laryngeal reinnervation (LR) has been suggested to provide "tone" to the paralyzed VF. This implies a loss of tone as a result of denervation without reinnervation. Read More

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http://dx.doi.org/10.1002/lary.27078DOI Listing
July 2018
4 Reads

Interpreting Signal Amplitudes in Surface Electromyography Studies in Sport and Rehabilitation Sciences.

Front Physiol 2017 4;8:985. Epub 2018 Jan 4.

Laboratory for Engineering of the Neuromuscular System, Department of Electronics and Telecommunications, Politecnico di Torino, Turin, Italy.

Surface electromyography (sEMG) is a popular research tool in sport and rehabilitation sciences. Common study designs include the comparison of sEMG amplitudes collected from different muscles as participants perform various exercises and techniques under different loads. Based on such comparisons, researchers attempt to draw conclusions concerning the neuro- and electrophysiological underpinning of force production and hypothesize about possible longitudinal adaptations, such as strength and hypertrophy. Read More

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http://dx.doi.org/10.3389/fphys.2017.00985DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5758546PMC
January 2018
3 Reads