Muscular Activity Research Articles

A new ICT system coupling electromyography and coma recovery scale-revised to support the diagnostic process in disorders of consciousness

The Coma Recovery Scale-revised (CRS-r) is the gold standard for the behavioral assessment of patients with Disorders of Consciousness (DoCs). However, the misdiagnosis rate is around 40%. For this reason, recent guidelines suggested enhancing the assessment with neurophysiological measures: among these, surface electromyography (sEMG) represents a convenient bedside solution. This work presents the use of the STRIVEfc system, a wearable device that allows CRS-r administration while recording four sEMG signals. STRIVEfc was employed in 40 sessions on 33 DoCs patients and the sEMG was analyzed to look for voluntary and consistent over threshold (OT) muscular activities. Their duration, amplitude, and number were retained and compared between patients in Unresponsive Wakefulness Syndrome (UWS) and Minimally Conscious State (MCS), revealing more numerous and significantly longer OTs in the latter group. Lastly, the EMG information was exploited to enrich the behavioral assessment by building the instrumented CRS-r score (ICRS-r). In 9/16 UWS sessions, the ICRS-r score suggested a higher-level functioning, not translated into a behavioral response, compatible with MCS diagnosis. Overall, the use of STRIVEfc allows to reveal hidden muscular patterns not detectable by the clinician, thus improving the characterization of DoCs patient’s functional capabilities and supporting the diagnostic process.

Correlations Between Mandibular Kinematics and Electromyography During the Masticatory Cycle: An Observational Study by Digital Analysis

The analysis of the masticatory cycle plays a fundamental role in studying the functions of the stomatognathic system and evaluating temporomandibular dysfunctions (TMD). The primary objective of this study is to investigate the complex interplay between mandibular kinematics and surface electromyography (sEMG) activity during the masticatory cycle using advanced 4D dentistry technology in 22 healthy subjects (without TMD). By employing electromyography, it becomes feasible to capture the electrical activity of the masticatory muscles throughout the chewing process. The BTS TMJOINT (© 2023 BTS Bioengineering, Garbagnate Milanese, MI, Italy) electromyograph was utilized in this study. Mandibular tracking, on the other hand, allows for recording the movements of the mandible during chewing and condylar slopes. This latest technology (ModJaw®, Tech in motion™, Villeurbanne, France) utilizes motion sensors placed on the jaw to accurately track three-dimensional movements, including jaw opening, closing, and lateral movements. Nowadays, in clinical gnathology, it is common practice to examine masticatory function by analyzing mandibular kinematics and muscle contraction as distinct entities. Similarly, the results obtained from these analyses are typically assessed independently. The investigation of a correlation between electromyography data and mandibular kinematics during the masticatory cycle could provide several advantages for clinicians in diagnosis and lead to a combined analysis of muscle activities and intraarticular dynamics. In conclusion, it can be inferred from the results obtained in the present study that the chewing cycle with a greater vertical movement results in increased masseter muscular activity, and condylar slopes are positively correlated to an increase in temporalis muscle activation. This comprehensive approach can provide valuable insights into the relationship between muscle activity and mandibular movement, enabling clinicians to gain a deeper understanding of the functional dynamics of the stomatognathic system.

AUTOMATED GESTURE RECOGNITION USING APPLIED LINGUISTICS WITH DATA-DRIVEN DEEP LEARNING FOR ARABIC SPEECH TRANSLATION

Gesture recognition for Arabic speech translation includes developing advanced technologies that correctly translate body and hand movements corresponding to Arabic sign language (ArSL) into spoken Arabic. This leverages machine learning and computer vision techniques in complex systems simulation platforms to scrutinize the gestures utilized in ArSL, detecting mild differences in facial expressions, hand shapes, and movements. Sign Language Recognition (SLR) is paramount in assisting communication for the Deaf and Hard-of-Hearing communities. It includes using vision-based methods and Surface Electromyography (sEMG) signals. The sEMG signal is crucial for recognizing hand gestures and capturing muscular activities in sign language. Researchers have comprehensively shown the capability of EMG signals to approach specific details, mainly in classifying hand gestures. This progression is a stimulating feature in extracting the interpretation and recognition of sign languages and investigating the phonology of signed language. Leveraging machine learning algorithms and signal processing techniques in complex systems simulation platforms, researchers aim to extract relevant traits from the sEMG signals that correspond to different ArSL gestures. This study introduces an Enhanced Dwarf Mongoose Algorithm with a Deep Learning-Driven Arabic Sign Language Detection (EDMODL-ASLD) technique on sEMG data. In the initial phase, the presented EDMODL-ASLD model is subjected to data preprocessing to change the input sEMG data into an attuned format. In the next stage, feature extraction with fractal theories is used to gather relevant and nonredundant data from the EMG window to construct a feature vector. In this study, the absolute envelope (AE), energy (E), root-mean square (RMS), standard deviation (STD), and mean absolute value (MAV) are the five time-domain extracted features for the EMG window observation. Meanwhile, the dilated convolutional long short-term memory (ConvLSTM) technique is used to identify distinct sign languages. To improve the results of the dilated ConvLSTM model, the hyperparameter selection process is executed using the EDMO model. To illustrate the significance of the EDMODL-ASLD technique, a brief experimental validation is made on the Arabic SLR database. The experimental validation of the EDMODL-ASLD technique portrayed a superior accuracy value of 96.47% over recent DL approaches.

Imaging modalities for atraumatic shoulder hypermobility: a scoping review.

Objective measures from imaging studies have the potential to assist in timely diagnosis of atraumatic shoulder hypermobility to better guide management. The aim of this scoping review is to examine imaging modalities and techniques used to characterize atraumatic shoulder hypermobility. MEDLINE, EMBASE, SPORTDiscus, Cochrane Library, and Web of Science were searched up to May 2024 for any primary study investigating imaging findings seen in atraumatic shoulder hypermobility. Patients with unilateral instability were excluded given its frequent association with traumatic origin. Eighteen observational studies met inclusion criteria. Results were divided into outcomes relating to capsular redundancy, glenohumeral anatomy, and muscle activation. Five studies using magnetic resonance arthrography (MRA) demonstrated statistically significant increases in capsular cross-sectional area (CSA), while a significant superior capsular elongation was reported by two studies in patients with multidirectional instability (MDI). Labrocapsular distance, glenocapsular ratio, and the presence of a combined sail and triangle sign on MRA were highly sensitive and specific parameters for identifying MDI. There were inconsistent findings for alterations of glenohumeral anatomy. Ultrasound assessments of acromiohumeral distance (AHD) were significantly increased in patients with MDI, but not in shoulders with hypermobility alone. Similarly, muscle activity measured by electromyography or glenohumeral translations differed significantly in patients with MDI, but not in those with hypermobility alone. Radiographic markers of capsular redundancy (e.g., CSA, labrocapsular distance, glenocapsular ratio), AHD, and muscular activity are useful in the diagnosis of MDI. However, there are no definitive imaging markers for diagnosing atraumatic shoulder hypermobility without MDI.

Social threat avoidance depends on action-outcome predictability

Avoiding threatening individuals is pivotal for adaptation to our social environment. Yet, it remains unclear whether social threat avoidance is subtended by goal-directed processes, in addition to stimulus-response associations. To test this, we manipulated outcome predictability during spontaneous approach/avoidance decisions from avatars displaying angry facial expressions. Across three virtual reality experiments, we showed that participants avoided more often when they could predict the outcome of their actions, indicating goal-directed processes. However, above-chance avoidance rate when facing unpredictable outcomes suggested that stimulus-response associations also played a role. We identified two latent classes of participants: the “goal-directed class” showed above-chance avoidance only in the predictable condition, while the “stimulus-response class” showed no credible difference between conditions but had a higher overall avoidance rate. The goal-directed class exhibited greater cardiac deceleration in the predictable condition, associated with better value integration in decision-making. Computationally, this class had an increased drift-rate in the predictable condition, reflecting increased value estimation of threat avoidance. In contrast, the stimulus-response class showed higher responsiveness to threat, indicated by increased drift-rate for avoidance and increased muscular activity at response time. These results support the central role of goal-directed processes in social threat avoidance and reveal its physiological and computational correlates.

Effects of Different Stretching Modalities on the Antagonist and Agonist Muscles on Isokinetic Strength and Vertical Jump Performance in Young Men.

Montalvo, S, Gonzalez, MP, Dietze-Hermosa, MS, Martinez, A, Rodriguez, S, Gomez, M, Ibarra-Mejia, G, Tan, E, and Dorgo, S. Effects of different stretching modalities on the antagonist and agonist muscles on isokinetic strength and vertical jump performance in young men. J Strength Cond Res XX(X): 000-000, 2024-Exercise warm-up may include static or dynamic stretching, impacting performance differently. This study investigated the effects of various stretching protocols on isokinetic strength, muscular activity, and vertical jump performance. Sixteen subjects, divided evenly between trained and untrained groups, underwent 8 distinct stretching conditions in random order. Outcomes measured included isokinetic knee extension and flexion torque and power, muscular activity (vastus lateralis, vastus medialis, and biceps femoris), and jump performance (jump height and modified reactive strength index [RSImod]). Responses to the stretching conditions were analyzed using a mixed-methods approach. For isokinetic knee extension, dynamic stretching of both agonist and antagonist (DY-AG-ANT) and combined dynamic agonist with static antagonist stretching (DY-AG ST-ANT) produced significant improvements. Dynamic stretching of both agonist and antagonist increased peak torque by 12.72% and average torque by 30.80%, while DY-AG ST-ANT increased peak torque by 15.61% and average torque by 41.06%. Muscular activity also improved significantly; DY-AG ST-ANT increased EMG activity of the vastus lateralis by 29.43% and vastus medialis by 70.75%. Biceps femoris saw a 33.18% increase with DY-AG and a 22.15% increase with ST-AG. Countermovement jump height improved with DY-AG-ANT (12.6%) and static antagonist (ST-ANT) conditions (11.3%) ( p < 0.05). Dynamic stretching of both agonist and antagonist also enhanced average power knee extension by 32.41%, while ST-AG DY-ANT improved it by 31.09% ( p < 0.05). Dynamic stretching, especially when combined with static stretching, optimizes isokinetic strength, muscular activity, and jump height. Coaches should incorporate dynamic stretching, alone or with static antagonist stretching, to maximize performance.

Muscle synergies during the walk-run and run-walk transitions.

Muscular synergies could represent the patterns of muscular activation used by the central nervous system (CNS) to simplify the production of movement. Studies in walking-running transitions described up to nine synergy modules, and an earlier activation of flexor and extension ankle muscular groups compared to running or walking. Our project aims to study the behaviour of muscle synergies in different stance and swing variations of walking-running (WRT) and running-walking (RWT) transitions. Twenty-four trained men participated in this study. A variable speed protocol on a treadmill was developed to record the activity of 14 muscle during walking, running and relative transitions. The protocol was based on five ramps of 50 seconds each around±10 and 20% of the WRT speed. WRT and RWT were identified according to an abrupt change of the duty factor. Analysing surface electromyography using non-negative matrix factorization (NMF) we obtained synergy modules and temporal activation profiles. Alpha threshold for statistical tests set at 0.05. We described four different transition strides, two for increasing speed transitions, and two for decreasing speed transitions. Four to six synergy modules were found in each condition. According to the maximum cosine similarity results, the two identified WRT conditions shared five modules, while the two RWT conditions shared four modules. WRT and RWT overall shared 4.33±0.58 modules. The activation profiles and centres of activation revealed differences among conditions. Transition occurred at step level, and transition strides were composed by walk-like and run-like steps. Compared with previous studies in running and walking, both transitions needed earlier activation of a comparable number of synergy modules. Synergies were affected by acceleration: during RWT the need to dissipate energy, to decrease the speed, was achieved by increasing the number of co-activating muscles. This was reflected in fewer synergy modules and different activation profiles compared to WRT. We believe that our results could be enforced in different applied fields, like clinical gait analysis, physiotherapy and rehabilitation, where plans including co-activation of specific muscular groups could be useful. Gait transitions are common in different sports, and therefore also application in training and sport science would be possible.

Development of an Electromyography Signal Acquisition Prototype and Statistical Validation Against a Commercial Device.

Electromyography (EMG) stands out as an accessible and inexpensive method for identifying muscle contractions on the surface and within deeper muscle tissues. Using specialized electronic circuits for amplification and filtering can help develop simple but effective systems for detecting and analyzing these signals. However, EMG devices developed by research teams frequently lack rigorous methodologies for validating the quality of the signals they record compared to those obtained by commercial systems that have undergone extensive testing and regulatory approval for market release. This underscores the critical need for standardized validation techniques to reliably assess the performance of experimental devices relative to established commercial equipment. Hence, this study introduces a methodology for the development and statistical validation of a laboratory EMG circuit compared with a professional device available on the market. The experiment simultaneously recorded the muscle electrical activity of 18 volunteers using two biosignal acquisition devices-a prototype EMG and a commercial system-both applied in parallel at the same recording site. Volunteers performed a series of finger and wrist extension movements to elicit myoelectric activity in these forearm muscles. To achieve this, it was necessary to develop not only the EMG signal conditioning board, but also two additional interface boards: one for enabling parallel recording on both devices and another for synchronizing the devices with the task programmatically controlled in Python that the volunteers were required to perform. The EMG signals generated during these tasks were recorded simultaneously by both devices. Subsequently, 22 feature indices commonly used for classifying muscular activity patterns were calculated from two-second temporal windows of the recordings to extract detailed temporal and spatial characteristics. Finally, the Mean Absolute Percentage Error (MAPE) was computed to compare the indices from the prototype with those from the commercial device, using this method as a validation system to assess the quality of the signals recorded by the prototype relative to the commercial equipment. A concordance of 87.6% was observed between the feature indices calculated from the recordings of both devices, suggesting high effectiveness and reliability of the EMG signals recorded by the prototype compared to the commercial device. These results validate the efficacy of our EMG prototype device and provide a solid foundation for the future evaluation of similar devices, ensuring their reliability, accuracy, and suitability for research or clinical applications.

Brain and Muscle derived features to discriminate simple hand motor tasks for a rehabilitative BCI: comparative study on healthy and post-stroke individuals.

Brain-Computer Interfaces targeting post-stroke recovery of the upper limb employ mainly electroencephalography to decode movement-related brain activation. Recently hybrid systems including muscular activity were introduced. We compared the motor task discrimination abilities of three different features, namely event-related desynchronization/synchronization (ERD/ERS) and movement-related cortical potential (MRCP) as brain-derived features and cortico-muscular coherence (CMC) as a hybrid brain-muscle derived feature, elicited in 13 healthy subjects and 13 stroke patients during the execution/attempt of two simple hand motor tasks (finger extension and grasping) commonly employed in upper limb rehabilitation protocols. &#xD;Approach. We employed a three-way statistical design to investigate whether their ability to discriminate the two movements follows a specific temporal evolution along the movement execution and is eventually different among the three features and between the two groups. We also investigated the differences in performance at the single-subject level.&#xD;Main results. The ERD/ERS and the CMC-based classification showed similar temporal evolutions of the performance with a significant increase in accuracy during the execution phase while MRCP-based accuracy peaked at movement onset. Such temporal dynamics were similar but slower in stroke patients when the movements were attempted with the affected hand. Moreover, CMC outperformed the two brain features in healthy subjects and stroke patients when performing the task with their unaffected hand, whereas a higher variability across subjects was observed in patients performing the tasks with their affected hand. Interestingly, brain features performed better in this latter condition with respect to healthy subjects. &#xD;Significance. Our results provide hints to improve the design of Brain-Computer Interfaces for post-stroke rehabilitation, emphasizing the need for personalized approaches tailored to patients' characteristics and to the intended rehabilitative target.

Simulating Upper Eyelid Ptosis During Neuromodulator Injections-An Exploratory Injection and Dissection Study.

Aesthetic neuromodulator injections of the upper face are frequently performed to temporarily block muscular actions of the periorbital muscles to ultimately reduce skin rhytids. However, the adverse event rate in the literature for toxin-induced blepharoptosis ranges from 0.51% to 5.4%. To identify access pathways by which injected neuromodulator product can travel from extra- to intra-orbital and therefore affect the levator palpebrae superioris muscle. Nine non-embalmed human body donors were investigated in this study with a mean age at death of 72.8 (16.1) years. The 18 supraorbital regions were injected in 28 times (14 for supratrochlear and 14 for supraorbital) with 0.5 cc, whereas eight cases (four for supratrochlear and four supraorbital) were injected with 0.1 cc of colored product. Anatomic dissections were conducted to identify structures stained by the injected color. The results of this injection- and dissection-based study revealed that both the supratrochlear and the supraorbital neurovascular bundles are access pathways for injected neuromodulator products to reach the intra-orbital space and affect the levator palpebrea superioris muscle. Out of 36 conducted injection passes, seven (19.44%) resulted in affection of the sole elevator of the eyelid of which 100% occurred only at an injection volume of 0.5 cc and not at 0.1 cc. Clinically, the results indicate that a low injection volume, a superficial injection for the supraorbital location, and angling the needle tip away from the supratrochlear foramen (toward the contralateral temple) when targeting the corrugator supercilii muscles, can increase the safety profile of an aesthetic toxin glabellar treatment.

Flexibar And Non-Flexibar Exercises And Its Effects On Trunk Activation- A Review Of Literature

Objective: To systematically review the randomised controlled trials to evaluate the effects of flexi-bar and non-flexi-bar exercises, specifically stabilization training, on trunk muscle activity in various postures. Methodology: The study included randomized control trials and clinical trials published between 2007-2018 , focusing on patients with upper trunk muscle weakness aged above 18. Exclusion criteria included a study with overlapping data, a study with associated disorders, or abstract-only papers. The search strategy involved a search of existing literature from databases like PubMed, Google Scholar, Cochrane Library, PEDro, and Research Gate, removing duplicates and identifying relevant articles. The full-text screening was performed, and the remaining relevant articles underwent data extraction. Surface electromyography (EMG) was used to measure the activity of selected trunk muscles, which was then normalized to maximum voluntary isometric contraction. Results: The findings of this study indicate that flexi-bar exercises resulted in higher activation of trunk muscles compared to non-flexi-bar exercises (stabilization training). The unique physical response induced by the vibration created through the swinging motion of the flexi bar triggered reflexive contractions of core muscles, leading to increased muscle activity. This suggests that flexi bar exercises may be beneficial in promoting muscular activation and potentially alleviating low back pain by evening out muscular imbalances.Conclusion: The results of this study support the use of flexi-bar exercises for activating trunk muscles, particularly when compared to non-flexi-bar exercises (stabilization training).

Vitamin D3 mitigates myopathy and metabolic dysfunction in rats with metabolic syndrome: the potential role of dipeptidyl peptidase-4.

Metabolic syndrome is associated with vitamin D3 deficiency. This work aims to examine the efficacy of vitamin D3 in inhibiting MetS-induced myopathy and to determine whether the beneficial effects of vitamin D3 are mediated by the inhibition of dipeptidyl peptidase-4 (DPP-4). An in silico study investigated the potential effectiveness of vitamin D3 on the inhibition of the DPP-4 enzyme. An in vitro assay of the DPP-4 inhibitory effect of vitamin D3 was performed. In vivo and over 12 weeks, both diet (with 3% salt) and drinking water (with 10% fructose) were utilized to induce MetS. In the seventh week, rats received either vitamin D3, vildagliptin, a combination of both, or vehicles. Serum lipids, adipokines, glycemic indices, and glucagon-like peptide-1 (GLP-1), muscular glucose transporter type-4 (GLUT-4) content, DPP-4, adenosine monophosphate kinase (AMPK) activities, and Sudan Black B-stained lipids were assessed. Muscular reactive oxygen species (ROS), caspase-3, and desmin immunostaining were used to determine myopathy. MetS-induced metabolic dysfunction was ameliorated by vitamin D3, which also reduced intramuscular glycogen and lipid accumulation. This is demonstrated by the attenuation of MetS-induced myopathy by vitamin D3, decreased oxidative stress, increased desmin immuno-expression, and caspase-3 activity. Our in silico data demonstrated that vitamin D3 is capable of inhibiting DPP-4, which is further supported by biochemical findings. Vitamin D3 increased serum GLP-1, muscular AMPK activity, and GLUT-4 content, whereas the levels of muscular ROS were decreased in MetS. Vildagliptin and its combination with vitamin D3 yielded comparable results. It is suggested that the DPP-4 inhibitory potential of vitamin D3 is responsible for the amelioration of MetS-induced metabolic changes and myopathy.

Comparative Effects of Different Focus Methods on Muscular Activation During Single-Leg-Squat Exercise

Background: Single-leg squats are frequently featured in training and rehabilitation programs. The use of focus during exercise changes the state of concentration during exercise. This causes changes in muscular activity. No study has been found comparing focusing methods’ effectiveness during single-leg squat movement. Aim: This study aims to compare the changes in lower extremity muscular activations in cases of external focus, internal focus, and absence of focus. Methods: The muscular activities (Gluteus Medius, Vastus Lateralis, Vastus Medialis, Rectus Femoris, Biceps Femoris, and Semitendinosus) of the healthy participants included in the study were measured with the surface electromyography (EMG) device. External focus, internal focus and without-focus positions were used. Results: Seventeen recreationally active participants were included in this study. The muscular activities of the participants, which occurred in three different situations, were measured with the surface electromyography (EMG) device. While the quadriceps were more active in the descent phase, the hamstring muscle group was more active in the ascent phase. The external focus provided more muscular activation than the other two focal conditions. Conclusion: According to the results of this study, the use of focus during single-leg squat training and rehabilitation may change the muscular response obtained.

Relationship Between Participation In Muscular Strengthening Activities And Perceived Stress Levels Among College Students

Relationship Between Participation In Muscular Strengthening Activities And Perceived Stress Levels Among College Students

Electromyographic analysis of bilateral upper trapezius muscles at different levels of work-pace among sewing machine operators

Workers are driven to work faster in the industrial work environment to meet high productivity targets. An increased work pace leads to increased muscle activation. However, the effect of work pace on bilateral upper trapezius muscles during sewing machine operation in an industrial work environment has not been thoroughly investigated in experimental studies. Therefore, this research aims to conduct an experimental study to analyze the bilateral upper trapezius muscle activity of industrial sewing machine operators at different levels of work pace. Thirty subjects (15 males, and 15 females) continuously performed the sewing operation for two hours in an industrial work environment. Experiments were conducted for two levels of work pace i.e. low pace (100% of standard cycle time) and high pace (120% of standard cycle time). Electromyographic signals were recorded from the bilateral upper trapezius muscles. The EMG amplitude (RMS) among the muscles was computed. A statistically significant (p < 0.05) increase in muscle activity was observed with an increased work pace. In this study, right upper trapezius muscle activity increased by 30.4% during high work pace tasks compared to low pace, while the left upper trapezius showed a 24.12% increase. The right upper trapezius showed a mean difference of 0.696 (%MVC), and the left upper trapezius showed 0.399 (%MVC), both indicating greater activity during high-pace tasks. The increase in muscle activity with time indicated the presence of muscle fatigue among sewing machine operators. Furthermore, higher muscular activity was observed among females than males. This research highlights the critical need to balance productivity goals with the health and safety of workers, reducing the risk of muscle fatigue and associated work-related musculoskeletal disorders.

Immunogram dynamics of students under the influence of dosed physical activity

Analysis of the dynamics of the state of blood leukocytes in muscular activity is relevant due to the development of methods of differentiation and assessment of the state of these cells. The purpose of the study is to study the dynamics of the phagocytic and NBT activity of neutrophils, as well as the content of CD lymphocytes of peripheral blood in students when moving on a treadmill. For students 18-20 years old involved in athletics (3 boys and 4 girls), blood was taken from the ulnar vein before and after a 15-minute jog, as well as after a 15-minute run of moderate intensity. The average level of physical performance of the examined PWC170 was 16.25±2.21 kGm/min/kg. Assessment of phagocytosis and NBT activity of neutrophils and determination of blood CD lymphocytes by immunophenotyping were performed using flow cytometry. It was found that in girls at rest, the relative content of lymphocytes and NK cells was significantly lower, and the level of induced NBT activity of neutrophils and the relative content of CD4-CD8- and CD4+CD8+ lymphocytes was significantly higher than in boys. At the same time, the dynamics of the leukogram parameters examined during the dosed physical activity fully corresponded to the development of the lymphocytic phase of myogenic leukocytosis. With an increase in the power of repeated exercise against the background of a general increase in the number of phagocytic neutrophils, the balance of spontaneous NBT-positive and reserve potentially active neutrophils significantly increased relative to the content of NBT-negative cells in the induced test. At the same time, the level of neutrocytes in girls was significantly higher, causing a higher level of phagocyte count and absolute content of NBT-positive neutrophils in a spontaneous and induced test. At the same time, against the background of an increase in the absolute content of CD4-CD8- and TNK lymphocytes, a statistically significant increase in the relative and absolute content of NK cells was observed. In contrast to the boys after the 2nd physical exercise, the relative and absolute content of NK cells, as well as the increase in the percentage of HBT-positive cells in the induced test, were significantly higher.

A Multimodal Bracelet to Acquire Muscular Activity and Gyroscopic Data to Study Sensor Fusion for Intent Detection.

Researchers have attempted to control robotic hands and prostheses through biosignals but could not match the human hand. Surface electromyography records electrical muscle activity using non-invasive electrodes and has been the primary method in most studies. While surface electromyography-based hand motion decoding shows promise, it has not yet met the requirements for reliable use. Combining different sensing modalities has been shown to improve hand gesture classification accuracy. This work introduces a multimodal bracelet that integrates a 24-channel force myography system with six commercial surface electromyography sensors, each containing a six-axis inertial measurement unit. The device's functionality was tested by acquiring muscular activity with the proposed device from five participants performing five different gestures in a random order. A random forest model was then used to classify the performed gestures from the acquired signal. The results confirmed the device's functionality, making it suitable to study sensor fusion for intent detection in future studies. The results showed that combining all modalities yielded the highest classification accuracies across all participants, reaching 92.3±2.6% on average, effectively reducing misclassifications by 37% and 22% compared to using surface electromyography and force myography individually as input signals, respectively. This demonstrates the potential benefits of sensor fusion for more robust and accurate hand gesture classification and paves the way for advanced control of robotic and prosthetic hands.

Advancements in Blind Source Separation for EEG Artifact Removal: A comparative analysis of Variational Mode Decomposition and Discrete Wavelet Transform approaches

Electroencephalography (EEG) is a vital tool for elucidating cerebral processes; however, it is inherently vulnerable to physiological interference, including cardiac rhythm, ocular movement, and muscular activity. To guarantee the reliability of essential neuronal data, it is imperative to implement efficacious denoising methodologies. This study compares the efficacy of two advanced blind source separation (BSS) techniques applied to EEG signals: variational mode decomposition-based BSS (VMD-BSS) and discrete wavelet transform-based BSS (DWT-BSS). The efficacy of these methods is rigorously assessed using performance metrics such as the Euclidean Distance (ED) and the Spearman Correlation Coefficient (SCC), which evaluate the precision of signal reconstruction and the correlation between the original and denoised signals, respectively. The findings indicate that both methods yield robust results, with minimal Euclidean distances of 704.04 for VMD-BSS and 703.64 for DWT-BSS, and a strong correlation coefficient of 0.82. The results demonstrate the effectiveness of the proposed techniques in removing artifacts while preserving essential neural information in EEG recordings. Furthermore, the proposed techniques are benchmarked against previous studies, considering factors such as signal properties, computational complexity, frequency localization, and flexibility. These findings highlight the importance of customized parameter selection tailored to the specific characteristics of EEG datasets and research objectives.

Maccarone et al.'s comments on Cohort studies using 3D-CT are needed to assess whether "home Gym-Bed" exercises are beneficial against sarcopenia.

We appreciate the insightful comments provided by Josef Finsterer regarding our article on the first evidence on the effects of the Home Full-Body in-Bed Gym protocol as a potential intervention to mitigate age-related muscle loss based on the preliminary positive results of a Padua prospective observational study.1 We acknowledge the importance of the points raised and would like to address them in this response. At the University of Padua, we conducted a study aimed at evaluating the impact of a home-based Full-Body in-Bed Gym protocol on various outcomes in elderly individuals, which was published in 2023.1 The rational of our proposal is based on the fact that functional muscle decay of aging is inevitable, but that the general population is highly hypoactive, let's say "lazy". The increase in daily muscular activity even through "Home In-Bed Gym" recovers at least in part the potential abilities progressively lost. Therefore, it is easy to rejuvenate the "lazy" population, that is, the vast majority of elderlies.[...].

Effects of platelet-rich plasma injection on electrical activity and biomechanics of the erector spinae muscles in lumbar myofascial pain syndrome

Low back pain (LBP) is a highly prevalent disease. Among the various causes of LBP, one of the most frequent is myofascial pain syndrome (MPS) which affects the spinal stabilizer muscles. The aims of this study were to compare the differences in muscular electrical activity and biomechanical properties between the painful and non-painful sides in patients with unilateral MPS and to verify the feasibility of surface electromyography (sEMG) and MyotonPRO for assisting in MPS assessment. Forty patients with unilateral lumbar MPS were recruited via the Department of Rehabilitation Medicine Center of West China Hospital Sichuan University from October 2022 to October 2023. The electrical properties of the bilateral erector spinae muscles were characterized by sEMG signals during a trunk extension task. The following four time-domain features of sEMG were extracted: root mean square (RMS), mean absolute value (MAV), integrated EMG (iEMG), and waveform length (WL). And two frequency domain features were extracted: the median frequency (MDF) and mean power frequency (MPF). The mechanical properties of the muscles were assessed by MyotonPRO at rest. The following biomechanical parameters were acquired: oscillation frequency [Hz], dynamic stiffness [N/m], logarithmic decrement, relaxation time [ms], and Creep. The visual analog scale (VAS) was used to evaluate the pain severity, and the Oswestry Disability Index (ODI) was used to evaluate the severity of disability and disruption to lifestyle activities caused by LBP pain. The outcome measures were obtained prior to the Platelet-rich plasma (PRP) treatment and repeated two weeks after treatment. (1) Prior to the PRP treatment, all sEMG time-domain features on the painful side were significantly higher than those on the non-painful side (RMS, p < 0.001; MAV, p < 0.001; iEMG, p < 0.001; WL, p = 0.001). However, there was no significant difference in the sEMG frequency-domain features (MPF, p = 0.478; MDF, p = 0.758). On the mechanical side, there were significant differences in oscillation frequency (p = 0.041) and logarithmic decrement (p = 0.022) between the painful side and non-painful side, but no significant differences in dynamic stiffness, relaxation time, and creep (both p > 0.05). (2) Two weeks after the PRP treatment, statistically significant decreases were observed in both post-treatment VAS (p < 0.001) and ODI scales (p < 0.001), indicating the PRP treatment clinically significantly reduced the level of. MPS. This change coincided with all sEMG time-domain features, in which the values at the painful side decreased significantly (RMS, p = 0.001; MAV, p = 0.001; iEMG, p = 0.001; WL, p = 0.001). However, no significant difference in the sEMG frequency-domain features (MPF, p = 0.620; MDF, p = 0.850) was found. On the mechanical side, only logarithmic decrement on the painful side increased significantly (p < 0.001). Our combined MyotonPRO and sEMG results indicated that MPS likely leads to increased muscle tone and decreased muscle elasticity, manifested by abnormal time-domain features of sEMG and biomechanical properties. The changes in these objective measurements were agreed with the changes in subjective outcome measures of pain and function currently assessed in the patients with MPS. A single PRP treatment may alleviate muscle dysfunction caused by MPS. These preliminary results demonstrated the potential feasibility of using sEMG and MyotonPRO as tools for assessing the neuromuscular function of MPS.