Journal of Electromyography and Kinesiology This is an RSS file. You can use it to subscribe to this data in your favourite RSS reader or to display this data on your own website or blog.

A New Method to Assess Passive and Active Ankle Stiffness during Quiet Upright Stance
Both passive and active ankle torque contribute to postural stability during quiet upright stance, yet directly measuring their relative contributions is difficult. Here, a new method was developed to estimate passive and active ankle stiffness (ST) and damping (DA). In contrast to earlier approaches, the proposed method does not require external mechanical or sensory perturbations. Instead, the method is based on the assumption that upright stance is intermittently controlled, and that active ankle torque is in-phase coherent with ankle angular acceleration. (Source: Journal of Electromyography and Kinesiology)
Source: Journal of Electromyography and Kinesiology - October 26, 2015 Category: Neurology Authors: Hongbo Zhang, Maury A. Nussbaum, Michael J. Agnew Source Type: research

Neuromuscular and physiological variables evolve independently when running immediately after cycling
During the early period of running after cycling, EMG patterns of the leg are modified in only some highly trained triathletes. The majority of studies have analysed muscle EMG patterns at arbitrary, predetermined time points. The purpose of this study was to examine changes to EMG patterns of the lower limb at physiologically determined times during the cycle-run transition period to better investigate neuromuscular adaptations. Six highly trained triathletes completed a 10 min isolated run (IR), 30 min of rest, then a 20 min cycling procedure, before a 10 min transition run (C-R). (Source: Journal of Electromyography and Kinesiology)
Source: Journal of Electromyography and Kinesiology - October 23, 2015 Category: Neurology Authors: Joel A. Walsh, Alexander Stamenkovic, Romuald Lepers, Gregory Peoples, Paul J. Stapley Source Type: research

Back muscle fatigue of younger and older adults with and without chronic low back pain using two protocols: A case-control study
The purpose of this study was to compare back muscle fatigue of younger and older participants with and without chronic low back pain (CLBP). Twenty participants without and 20 with nonspecific CLBP participated in this study. Each group contained 10 younger (50% males; mean age: 31±6 yrs) and 10 older adults (50% males; age mean: 71±7.5 yrs). Two isometric fatigue protocols were presented randomly: (1) to maintain the unsupported trunk at the horizontal position while on a 45° Roman chair for a minute, and (2) to maintain a 10% of body weight box close to the trunk in the upright position for a minute. (Source: Journal...
Source: Journal of Electromyography and Kinesiology - October 22, 2015 Category: Neurology Authors: Rubens A. da Silva, Edgar R. Vieira, Marcos Cabrera, Leandro R. Altimari, Andreo F. Aguiar, Alexandre H. Nowotny, Adriana F. Carvalho, Marcio R. Oliveira Source Type: research

Hip joint motion and gluteal muscle activation differences between healthy controls and those with varying degrees of hip osteoarthritis during walking
PurposeCompare gluteal muscle activation patterns and three-dimensional hip joint movements among those with severe hip osteoarthritis (OA), moderate OA and a healthy group during walking.Scope: 20 individuals with severe OA, 20 with moderate OA and 20 healthy individuals were recruited. Three-dimensional hip motion and surface electromyograms from gluteus maximus and medius were collected during treadmill walking at a self-selected speed. Angular displacement characteristics were calculated for three-dimensional hip motions. (Source: Journal of Electromyography and Kinesiology)
Source: Journal of Electromyography and Kinesiology - October 22, 2015 Category: Neurology Authors: Derek Rutherford, Janice Moreside, Ivan Wong Source Type: research

Pain intensity attenuates movement control of the lumbar spine in low back pain
Pain intensity attenuates muscular activity, proprioception, and tactile acuity, with consequent changes of joint kinematics. People suffering from low back pain (LBP) frequently show movement control impairments of the lumbar spine in sagittal plane. This cross-sectional, observational study investigated if the intensity of LBP attenuates lumbar movement control. The hypothesis was that lumbar movement control becomes more limited with increased pain intensity. (Source: Journal of Electromyography and Kinesiology)
Source: Journal of Electromyography and Kinesiology - October 19, 2015 Category: Neurology Authors: C.M. Bauer, F.M. Rast, M.J. Ernst, S. Oetiker, A. Meichtry, J. Kool, S.M. Rissanen, J.H. Suni, M. Kankaanpää Source Type: research

From the outgoing editor in chief
The last issue of 2015 marked 25 years since the Journal of Electromyography & Kinesiology was founded and with that 25 years of my service as its Editor. The incoming Editor in Chief, Prof Dario Farina, is an accomplished scientist with vast experience in EMG and its use in kinesiology, sports and rehabilitation in addition to the techniques used to record and analyze EMG. I am sure the journal is in highly competent hands for the years to come. (Source: Journal of Electromyography and Kinesiology)
Source: Journal of Electromyography and Kinesiology - October 16, 2015 Category: Neurology Authors: Moshe Solomonow Source Type: research

Electromechanical delay of the hamstrings during eccentric muscle actions in males and females: Implications for non-contact ACL injuries
This study recruited 110 participants (55 males, 55 females) and electromyography of the semitendionosis, semimembranosus and biceps femoris was determined during eccentric actions at 60, 120 and 240°/s. (Source: Journal of Electromyography and Kinesiology)
Source: Journal of Electromyography and Kinesiology - October 15, 2015 Category: Neurology Authors: Mark B.A. De Ste Croix, Youssif O. ElNagar, John Iga, David James, Francisco Ayala Source Type: research

Dynamic balance in elite karateka
In karate, balance control represents a key performance determinant. With the hypothesis that high-level athletes display advanced balance abilities, the purpose of the current study was to quantitatively investigate the motor strategies adopted by elite and non-elite karateka to maintain balance control in competition. The execution of traditional karate techniques (kihon) in two groups of elite Masters (n=6, 31±19 years) and non-elite Practitioners (n=4, 25±9 years) was compared assessing body center of mass (CoM) kinematics and other relevant parameters like step width and angular joint behavior. (Source: Journal of E...
Source: Journal of Electromyography and Kinesiology - October 13, 2015 Category: Neurology Authors: Matteo Zago, Andrea Mapelli, Yuri Francesca Shirai, Daniela Ciprandi, Nicola ovecchio, Christel Galvani, Chiarella Sforza Source Type: research

Effect of interelectrode distance on surface electromyographic signals of vastus intermedius muscle in women and men
We previously developed a novel technique to record surface electromyography (EMG) of the vastus intermedius (VI) in men. The purpose of the present study was to assess whether this technique can be applied to women in the same way. We measured the subcutaneous fat thickness at the site of electrode placement on VI using ultrasonography. Nine men and ten women performed isometric knee extensions at 25, 50, 75, and 100% of the maximal voluntary contraction. During the tasks, surface EMG signals were recorded from the superficial region of VI with interelectrode distances (IEDs) of 10 mm (IED-10) and 20 mm (IED-20). (Source:...
Source: Journal of Electromyography and Kinesiology - October 9, 2015 Category: Neurology Authors: Aya Tomita, Ryosuke Ando, Akira Saito, Kohei Watanabe, Hiroshi Akima Source Type: research

Muscle Stiffness Estimation using a System Identification Technique Applied to Evoked Mechanomyogram during Cycling Exercise
The aims of this study were to develop a method to extract the evoked mechanomyogram (MMG) during cycling exercise and to clarify muscle stiffness at various cadences, workloads, and power. Ten young healthy male participants were instructed to pedal a cycle ergometer at cadences of 40 and 60 rpm. The loads were 4.9, 9.8, 14.7, and 19.6 N, respectively. One electrical stimulus per two pedal rotations was applied to the vastus lateralis muscle at a knee angle of 80° in the down phase. MMGs were measured using a capacitor microphone, and the MMGs were divided into stimulated and non-stimulated sequences. (Source: Journal of...
Source: Journal of Electromyography and Kinesiology - October 8, 2015 Category: Neurology Authors: Takanori Uchiyama, Kaito Saito, Katsuya Shinjo Source Type: research

Patterns of muscle coordination during stepping responses post-stroke
This study compared self-induced stepping reactions of seventeen participants after stroke and seventeen controls. Surface electromyographic (EMG) signals were recorded bilaterally from the soleus (SOL), tibialis anterior (TA), biceps femoris (BF) and rectus femoris (RF) muscles. Principal component analysis (PCA) was used to reduce the data into muscle activation patterns and examine group differences (paretic, non-paretic, control leg). The first principal component (PC1) explained 46.7% of the EMG signal of the stepping leg. (Source: Journal of Electromyography and Kinesiology)
Source: Journal of Electromyography and Kinesiology - October 6, 2015 Category: Neurology Authors: V.L. Gray, C.L. Pollock, J.M. Wakeling, T.D. Ivanova, S.J. Garland Source Type: research

The EMG activity–acceleration relationship to quantify the optimal vibration load when applying synchronous whole-body vibration
Purpose: To date are lacking methodological approaches to individualizing whole-body vibration (WBV) intensity. The aim of this study was: (1) to determine the surface-electromyography-root-mean-square (sEMGRMS)–acceleration load relationship in the vastus lateralis (VL), vastus medialis (VM), rectus femoris (RF), lateral gastrocnemius (LG) muscles during synchronous WBV, and (2) to assess the reliability of the acceleration corresponding to the maximal sEMGRMS. Methods: Twenty-five sportsman voluntarily took part in this study with a single-group, repeated-measures design. (Source: Journal of Electromyography and Kinesiology)
Source: Journal of Electromyography and Kinesiology - September 21, 2015 Category: Neurology Authors: Riccardo Di Giminiani, Francesco Masedu, Johnny Padulo, Jozsef Tihanyi, Marco Valenti Source Type: research

The EMG activity-acceleration relationship to quantify the optimal vibration load when applying synchronous whole-body vibration
To date are lacking methodological approaches to individualizing whole-body vibration (WBV) intensity. The aim of this study was: (1) to determine the surface-electromyography-root- mean-square (sEMGRMS)-acceleration load relationship in the vastus lateralis (VL), vastus medialis (VM), rectus femoris (RF), lateral gastrocnemius (LG) muscles during synchronous WBV, and (2) to assess the reliability of the acceleration corresponding to the maximal sEMGRMS. (Source: Journal of Electromyography and Kinesiology)
Source: Journal of Electromyography and Kinesiology - September 21, 2015 Category: Neurology Authors: Riccardo Di Giminiani, Francesco Masedu, Johnny Padulo, Jozsef Tihanyi, Marco Valenti Source Type: research

Homogeneity of fascicle architecture following repeated contractions in the human gastrocnemius medialis
This investigation sought to determine the effects of fatigue on fascicle architecture across the length of the human gastrocnemius medialis (GM). With institutional ethical approval, fifteen healthy males performed repeated isometric plantar flexion maximal voluntary contractions (MVC) until peak force fell 30% below baseline. Brightness-mode ultrasound was used to determine fascicle length and pennation angle at rest and during MVC prior to and following the fatiguing contractions. The results show a significant increase in fascicle length during MVC in the distal (2.8mm, 8.1%) middle, (4.9mm, 14.1%), and proximal (5.2mm...
Source: Journal of Electromyography and Kinesiology - September 12, 2015 Category: Neurology Authors: Neil M. Thomas, Susan Dewhurst, Theodoros M. Bampouras Source Type: research

Older adults utilize less efficient postural control when performing pushing task
The ability to maintain balance deteriorates with increasing age. The aim was to investigate the role of age in generation of anticipatory (APA) and compensatory (CPA) postural adjustments during pushing an object. Older (68.8 ± 1.0 years) and young adults (30.1 ± 1.4 years) participated in the experiment involving pushing an object (a pendulum attached to the ceiling) using both hands. Electrical activity of six leg and trunk muscles and displacements of the center of pressure (COP) were recorded and analyzed during the APA and CPA phases. (Source: Journal of Electromyography and Kinesiology)
Source: Journal of Electromyography and Kinesiology - September 9, 2015 Category: Neurology Authors: Yun-Ju Lee, Bing Chen, Alexander S. Aruin Source Type: research