Taian Martins Vieira

Polytechnic University of Turin | polito · DET - Department of Electronics and Telecommunications

Segmentation of running data into gait cycles and stance/swing phases is crucial for evaluating running biomechanics. The benefit of magneto-inertial sensors is their ability to capture data in outdoor conditions. However, state-of-the-art inertial-based methods for estimating running temporal parameters are limited to a restricted range of running...

This paper aims to introduce HDE-Array (High-Density Electrode Array), a novel dry electrode array for acquiring High-Density surface electromyography (HD-sEMG) for hand position estimation through RPC-Net (Recursive Prosthetic Control Network), a neural network defined in a previous study. We aim to demonstrate the hypothesis that the position est...

Context: This systematic review investigated the effects of plyometric exercise interventions on proprioception. Methods: An electronic search was conducted in October 2022 across eight databases: PubMed, Scopus, ProQuest, Science Direct, Google Scholar, DOAJ, IEEE Xplore, and Cochrane. To be included in the review, studies had to meet all the esta...

The upper trapezius muscle is often excessively excited during resistance training exercises, increasing the shoulder’s liability to musculoskeletal disorders of individuals participating in overhead sports or throwing activities. Different approaches have been proposed for reducing the potentially harmful loading of the upper trapezius. None, howe...

Tongue motor function is crucial in a wide range of basic activities and its impairment affects quality of life. The electrophysiological assessment of the tongue relies primarily on needle electromyography, which is limited by its invasiveness and inability to capture the concurrent activity of the different tongue muscles. This work aimed at deve...

After a stroke, antagonist muscle activation during agonist command impedes movement. This study compared measurements of antagonist muscle activation using surface bipolar EMG in the gastrocnemius medialis (GM) and high-density (HD) EMG in the GM and soleus (SO) during isometric submaximal and maximal dorsiflexion efforts, with knee flexed and ext...

UNSTRUCTURED Sport science and rehabilitation are naturally evolving towards the implementation of data-driven technology for the analysis of human motion. Analysis of movement has traditionally been taught, researched, and implemented in practice either visually, or using equipment often unavailable outside specialized research centers. The motion...

The CNS may produce the same endpoint trajectory or torque profile with different muscle activation patterns. What differentiates these patterns is the presence of co-contraction, which does not contribute to effective torque generation but allows to modulate joints' mechanical stiffness. While it has been suggested that the generation of force and...

Background The application of lower limb traction during hip arthroscopy and femur fractures osteosynthesis is commonplace in orthopaedic surgeries. Traditional methods utilize a perineal post on a traction table, leading to soft tissue damage and nerve neuropraxia. A postless technique, using high-friction pads, has been considered as a potential...

The clinical effects of a serious game with electromyography feedback (EMGs_SG) and physical therapy (PT) was investigated prospectively in children with unilateral spastic cerebral palsy (USCP). An additional aim was to better understand the influence of muscle shortening on function. Thirty children with USCP (age 7.6 ± 2.1 years) received four w...

Objective: The firing instants of single motor units (MUs) can be identified by decomposing electromyograms (EMG) detected with intramuscular or grids of surface electrodes. The latter is sometimes preferred due to its larger detection volume and non-invasiveness. When the interest is in firing instants and not in investigating the activity of spec...

Objective: The purpose of this study was to develop and evaluate the performance of RPC-Net (Recursive Prosthetic Control Network), a novel method using simple neural network architectures to translate electromyographic activity into hand position with high accuracy and computational efficiency. Methods: RPC-Net uses a regression-based approach...

Introduction Eccentric exercise has often been reported to result in muscle damage, limiting the muscle potential to produce force. However, understanding whether these adverse consequences extend to a broader, functional level is of apparently less concern. In this study, we address this issue by investigating the acute and delayed effects of supr...

The value of surface electromyograms (EMGs) lies in their potential to non-invasively probe the neuromuscular system. Whether muscle excitation may be accurately inferred from bipolar EMGs depends on how much the detected signal is both sensitive and specific to the excitation of the target muscle. While both are known to be a function of inter-ele...

Ageing is associated with neuromuscular system changes that may have implications for the recruitment and firing behaviours of motor units (MUs). In previous studies, we observed that young adults recruit sub-populations of triceps surae MUs during tasks that involved leaning in multiple directions: common units that were active during different le...

This study aims to compare two methods for the identification of anatomical and mechanical motor unit (MU) properties through the integration of high-density surface electromyography (HDsEMG) and ultrafast ultrasound (UUS). The two approaches rely on a combined analysis of the firing pattern of active MUs, identified from HDsEMG, and tissue velocit...

Stride-and step-segmented running parameters provide valuable information in the study of the running biomechanics and performance. However, segmentation requires accurate identification of initial and final foot contact events (IC and FC). Inertial sensors (IMUs) are the most effective solution for in-field running analysis. Although the morpholog...

Predictors and mitigators of strain injuries have been studied in sprint‐related sports. While the rate of axial strain, and thus running speed, may determine the site of muscle failure, muscle excitation seemingly offers protection against failure. It seems therefore plausible to ask whether running at different speeds changes the distribution of...

Surface electromyography (sEMG) is a signal consisting of different motor unit action potential trains and records from the surface of the muscles. One of the applications of sEMG is the estimation of muscle force. We proposed a new real-time convex and interpretable model for solving the sEMG—force estimation. We validated it on the upper limb dur...

The degeneration of lower motoneurons has often been reported in stroke survivors, with possible collateral reinnervation from the surviving motoneurons to the denervated muscle fibers. Under this assumption, a stroke would be expected to increase the size of motor units in paretic muscles. We indirectly address this issue with electrical stimulati...

Background Successfully controlling head posture demands the integration of sensory information arising from different receptors. Of particular interest is the influence of feet mechanoreceptors on the control of head position in space.AimWe ask whether a thin plantar insert can modify the range of motion (RoM) of the head and whether changes in Ro...

It has been shown that when humans lean in various directions, the central nervous system (CNS) recruits different motoneuron pools for task completion; common units that are active during different leaning directions, and unique units that are active in only one leaning direction. We used high-density surface electromyography (HD-sEMG) to examine...

Biofeedback based on electromyograms (EMGs) has been recently proposed to reduce exaggerated postural activity. Whether the effect of EMG biofeedback on the targeted muscles generalizes to – or is compensated by – other muscles is still an open question we address here. Fourteen young individuals were tested in three 60 s standing trials, without a...

Conflictual results between the onset of vastus medialis (VM) and vastus lateralis (VL) excitation may arise from methodological aspects related to the detection of surface electromyograms. In this study we used an array of surface electrodes to assess the effect of detection site, relative to the muscle innervation zone, on the difference between...

A preliminary investigation on three different methods for the detection of initial contact (IC) events during running: two from the litterature, one newly proposed. The results obtained via the different methods have been compared with the gold standard (pressure insoles) to evaluate the performances of the three in terms of IC identification and...

The CNS may produce the same endpoint trajectory or torque profile with different muscle activation patterns. What differentiates these patterns is the presence of co-contraction, which does not contribute to joint torque generation but allows to modulate mechanical impedance. Whether co-contraction is controlled through the same synaptic input to...

Different mechanisms of force transmission have been developed for the movement of wheelchairs, from the standard pushrim propulsion to the handbike. Contributing to this repertoire, we recently developed a system of propulsion based on a pulley-cable mechanism, the Handwheelchair.Q. In contrast to other propulsion systems, the Handwheelchair.Q req...

Surface electromyograms (EMGs) have been often used to study muscle function in locomotor activities. Typically, EMGs are sampled with a single pair of electrodes, providing information on the timing and degree of muscle excitation. Additional information may be obtained when sampling EMGs with multiple electrodes from the same, target muscles. Stu...

It is clear from non-human animal work that spinal motoneurones undergo endurance training (chronic) and locomotor (acute) related changes in their electrical properties and thus their ability to fire action potentials in response to synaptic input. The functional implications of these changes, however, are speculative. In humans, data suggests tha...

Electromyography and ultrasonography provide complementary information about electrophysiological and physical (i.e. anatomical and mechanical) muscle properties. In this study, we propose a method to assess the electrical and physical properties of single motor units (MUs) by combining High-Density surface Electromyography (HDsEMG) and ultrafast u...

Background and objectives Professional pianists tend to develop playing-related musculoskeletal disorders mostly in the forearm. These injuries are often due to overuse, suggesting the existence of a common forearm region where muscles are often excited during piano playing across subjects. Here we use a grid of electrodes to test this hypothesis,...

Surface electromyography amplitudes are commonly measured in acute sports and exercise science studies to make inferences about muscular strength, performance, and hypertrophic adaptations that may result from different exercises or exercise-related variables. Here, we discuss the presumptive logic and assumptions underlying these inferences, focus...

Work-related musculoskeletal disorders, reported at shoulder and low back regions, rank among the most serious health problems in industry. Owing to their ability in providing support to the shoulder and back regions during sustained and repetitive tasks, passive exoskeletons are expected to prevent work-related disorders. In this work, experimenta...

Neuromuscular electrical stimulation finds application in several fields, from basic neurophysiology, to motor rehabilitation and cardiovascular conditioning. Despite the progressively increasing interest in this technique, its State-of-the-Art technology is mainly based on monolithic, mostly wired devices, leading to two main issues. First, these...

Non‐physiological sources may lead to equivocal interpretation on the degree of muscle excitation from electromyograms (EMGs) amplitude. This presumably explains the contradictory findings regarding the effect of the bench press inclination on the pectoralis major (PM) activation pattern. To contend with these issues, herein we used high‐density su...

The purpose of this study is to investigate whether regional modulation of the ankle plantarflexors during standing was related to the recruitment of motor units associated with force direction. Fourteen participants performed a multi-directional leaning task in standing. Participants stood on a force platform and maintained their center of pressur...

Muscle fasciculations, resulting from the spontaneous activation of motor neurons, may be associated with neurological disorders, and are often assessed with intramuscular electromyography (EMG). Recently, however, both ultrasound (US) imaging and multichannel surface EMG have been shown to be more sensitive to fasciculations. In this study we comb...

Muscle activity monitoring in dynamic conditions is a crucial need in different scenarios, ranging from sport to rehabilitation science and applied physiology. The acquisition of surface electromyographic (sEMG) signals by means of grids of electrodes (High-Density sEMG, HD-sEMG) allows to obtain relevant information on muscle function and recruitm...

Abstract Background Altered regional activation of the lumbar extensors has been previously observed in individuals with low back pain (LBP) performing high-effort and fatiguing tasks. It is currently unknown whether similar alterations can be observed during low-effort functional tasks. Similarly, previous studies did not investigate whether side...

Bi-articular muscles have traditionally been considered to exhibit homogeneous neuromuscular activation. The regional activation of bi-articular muscles, as revealed from high-density surface electromyograms, seems however to discredit this notion. We thus hypothesize the regional activation of bi-articular muscles may contribute to different actio...

When sampling electromyograms (EMGs) with one pair of electrodes, it seems implicitly assumed the detected signal reflects the net muscle excitation. However, this assumption is discredited by observations of local muscle excitation. Therefore, we hypothesize that the accurate assessment of muscle excitation requires multiple EMG detection and cons...

Computational modelling is a powerful tool in biomechanical studies. Open-source software OpenSim provides different musculoskeletal models. However, existing upper body models consider only one limb, which could be a limitation in reproducing two-handed tasks. The purpose of this research was to develop a two upper limbs model that can be customiz...

Purpose: Previous evidence from surface electromyograms (EMGs) suggests that exercise-induced muscle damage (EIMD) may manifest unevenly within the muscle. Here we investigated whether these regional changes were indeed associated with EIMD or if they were attributed to spurious factors often affecting EMGs. Methods: Ten healthy male subjects perf...

In this study we used the bipolar surface electromyography to investigate whether a passive exoskeleton reduces the degree of activity of shoulder muscles. Twelve young healthy volunteers participated in the study. Subjects were asked to hold four different static postures: (P1) shoulder abducted at 90°, elbow flexed at 90°, elbow pronated at 90°;...

When sampling electromyograms (EMGs) with one pair of electrodes, it appears implicitly assumed the detected signal reflects the net, muscle excitation. This assumption is however discredited by observations of local muscle excitation. We therefore hypothesize the accurate assessment of muscle excitation requires multiple EMG detection and consider...

Objective: We recently documented that compound muscle action potentials (M waves) recorded over the "pennate" vastus lateralis showed a sharp deflection (named as shoulder) in the first phase. Here, we investigated whether such shoulder was also present in M waves evoked in a muscle with different architecture, such as the biceps brachii, with th...

Since one of the major consequences of stroke is hemiparesis, the rehabilitation of upper limbs is necessary to improve the quality of life. Arm cranking gesture represents an alternative rehabilitation tool, especially if accompanied by a biofeedback involving and motivating patients. The aim of this pilot study was twofold: (1) to evaluate the ef...

The surface electromyography (sEMG) records the electrical activity of muscle fibers during contraction: one of its uses is to assess changes taking place within muscles in the course of a fatiguing contraction to provide insights into our understanding of muscle fatigue in training protocols and rehabilitation medicine. Until recently, these myoel...

Individuals with multiple sclerosis (MS) experience progressive declines in movement capabilities, especially walking performance. The purpose of our study was to compare the amount of variance in walking performance that could be explained by the functional capabilities of lower leg muscles in persons with MS and a sex- and age-matched control gro...

PurposeDifferent motor units (MUs) in the biceps brachii (BB) muscle have been shown to be preferentially recruited during either elbow flexion or supination. Whether these different units reside within different regions is an open issue. In this study, we tested wheter MUs recruited during submaximal isometric tasks of elbow flexion and supination...

The transcutaneous stimulation of lower limb muscles during indoor rowing (FES Rowing) has led to a new sport and recreation and significantly increased health benefits in paraplegia. Stimulation is often delivered to quadriceps and hamstrings; this muscle selection seems based on intuition and not biomechanics and is likely suboptimal. Here, we sa...

It is well established that muscle percussion may lead to the excitation of muscle fibres. It is still debated, however, whether the excitation arises directly at the percussion site or reflexively, at the end plates. Here we sampled surface electromyograms (EMGs) from multiple locations along human vastus medialis fibres to address this issue. In...

Maintenance of upright standing posture has often been explained using the inverted pendulum model. This model considers the ankle plantarflexors to act as a single synergistic group. There are differences in muscle properties among the medial and lateral gastrocnemius (MG and LG, respectively) and the soleus that may affect their activation. Twelv...

The study was undertaken to examine separately the potentiation of the first and second phases of the M wave in biceps brachii after conditioning maximal voluntary contractions (MVCs) of different durations. M waves were evoked in the biceps brachii muscle before and after isometric MVCs of 1, 3, 6, 10, 30, and 60 s. The amplitude, duration, and ar...

Background: Ankle plantarflexor muscle impairment contributes to asymmetrical postural control poststroke. Objective: This study examines the relationship of plantarflexor electromyography (EMG) with anterior-posterior center of pressure (APCOP) in people poststroke during progressive challenges to standing balance. Methods: Ten people poststroke a...

The use of electrical stimulation to elicit single twitches and tetanic contractions of skeletal muscles has increased markedly in the last years, with applications ranging from basic physiology to clinical settings. Addressing all possible needs required by different applications with an electrical stimulator is challenging as it requires the devi...

The clinical standard for the identification of muscle fasciculations is needle electromyography. However, both surface electromyograms (sEMG) and ultrasound imaging (US) have been recently proposed as alternative and more sensitive approaches. The aims of this study were to: (i) compare the sensitivity to muscle fasciculations of sEMG and US, (ii)...

Neuromuscular adaptations are well-reported in stroke survivors. The death of motor neurons and the reinnervation of residual muscle fibers by surviving motor neurons, for example, seem to explain the increased density of muscle units after stroke. It is, however, unknown whether reinnervation takes place locally or extensively within the muscle. H...

Changes in innervation zone (IZ) position may affect the amplitude of surface electromyograms (EMGs). If not accounted for, these changes may lead to equivocal interpretation on the degree of muscle activity from EMG amplitude. In this study we ask how much the IZ position changes within different regions of the pectoralis major (PM) during the ben...

Notwithstanding recent advances in the detection and processing techniques, a new critical issue is emerging in surface electromyography: the spatial localisation of muscle activity. This issue has direct impact on the estimation of muscle activity, normalisation, cross-talk and myoelectric fatigue, and therefore on the correct interpretation of su...

In this manuscript we describe the development and testing of a bipolar electrode for the simultaneous acquisition of ultrasound (US) images and surface electromyograms (EMGs) from the same muscle region. The developed electrode (bEMG-US) consists of two circular sensing regions (20 mm diameter) with fixed inter-electrode distance (3.5 cm, center-t...