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Rev. bras. ortop ; 58(2): 290-294, Mar.-Apr. 2023. tab
Article in English | LILACS | ID: biblio-1449802


Abstract Objective Given the divergence of opinions on the need for complementary tests such as ultrasonography (US) and electroneuromyography (ENMG) for the diagnosis of carpal tunnel syndrome (CTS), we aimed to elucidate which of them presents greater accuracy for the confirmation of the presence or not of this condition. Methods A total of 175 patients from a hand surgery outpatient clinic were clinically evaluated, and the results of clinical trials (Tinel, Phalen and Durkan), US (normal or altered), and ENMG (normal, mild, moderate and severe) were noted, crossed, and submitted to a statistical analysis to verify the agreement between them. Results with the sample had a mean age of 53 years, with a prevalence of female patients (159 cases). Of the patients with positive clinical test, 43.7% had normal US and 41.7% had no alterations on the ENMG. Negative results were found on the Tinel in 46.9%, on the Phalen in 47.4%, and on the Durkan in 39.7%. In the crossing between the results of the ENMG and those of the other diagnostic methods, there was little statistical agreement between them. Conclusion There was no agreement between the results of the clinical examinations, the US and the ENMG in the diagnosis of CTS, and there is no clinical or complementary examination for CTS that accurately determines the therapeutic approach. Level of Evidence IV, Case Series.

Resumo Objetivo Diante da divergência sobre a necessidade de exames complementares, como ultrassonografia (US) e eletroneuromiografia (ENMG) para o diagnóstico da síndrome do túnel do carpo (STC), objetivamos elucidar qual deles apresenta maior precisão na confirmação da presença ou não desta afecção. Métodos Um total de 175 pacientes de um ambulatório de cirurgia da mão foram avaliados clinicamente, e os resultados dos testes clínicos (Tinel, Phalen e Durkan), da US (normal ou alterada) e da ENMG (normal, leve, moderada e grave) foram anotados, cruzados, e submetidos a análise estatística para verificar a concordância entre eles. Resultados A idade média da amostra era de 53 anos, sendo prevalente o sexo feminino (159 casos). Dos pacientes com teste clínico positivo, 43,7% apresentavam US normal, e 41,7%, ENMG sem alterações. Foram encontrados resultados negativos no Tinel em 46,9% no Phalen em 47,4%, e no Durkan em 39,7%. No cruzamento entre a ENMG e os demais métodos diagnósticos, houve pouca concordância estatística. Conclusão Não houve concordância entre os resultados dos exames clínicos, da US e da ENMG no diagnóstico da STC, e não há exame clínico ou complementar para STC que determine a conduta terapêutica com precisão. Nível de Evidência IV, Série de Casos.

Humans , Paresthesia , Carpal Tunnel Syndrome/diagnosis , Median Neuropathy/diagnosis , Electromyography
Braz. j. oral sci ; 22: e230961, Jan.-Dec. 2023. ilus
Article in English | LILACS, BBO | ID: biblio-1442826


There is no consensus on the most appropriate method for normalizing electromyography (EMG) signals from masticatory muscles during isotonic activity. Aim: To analyze the best method for data processing of the EMG signal of the masticatory muscles during isotonic activity (non-habitual chewing), comparing raw data and different types of normalization. Methods: This is a cross-sectional study. Women aged between 18 and 45 years were selected. Anthropometric data were collected (age, height, body mass index ­ BMI, masticatory preference) as well as EMG signal (root mean square ­ RMS) data for the anterior temporal and masseter bilaterally, and for the suprahyoid muscles, during isotonic (non-habitual chewing) and isometric tasks. EMG data were processed offline using Matlab® Software. The normalization of the EMG signal was carried out using the 2nd masticatory cycle, chosen at random, of the 20 cycles collected, the maximum RMS value, and the maximum voluntary contraction (MVC). To analyze the best method of data processing for the isotonic data, the coefficient of variation (CV) was calculated. Descriptive data analysis was adopted, using the mean and standard deviation. ANOVA with repeated measures was used to detect significant differences between the methods of normalization. Statistical significance was set at 5% (α<0.05). Results: The final sample of this research was composed of 86 women. The volunteers presented an average age of 27.83±7.71 years and a mean BMI of 22.85±1.91 Kg/m2. Regarding masticatory preference, 73.25% reported the right side, and 26.75% the left side. Considering the comparison between the methods, the %CV measure of the 2nd cycle showed the lowest variation coefficient during biting for all the muscles from the raw data, RMS Max, and MVC (p=0.001, p=0.003, and p=0.001 respectively). Conclusion: In conclusion, for non-habitual chewing activity, the results of this study recommend data processing using normalization with the second cycle during chewing

Humans , Female , Adult , Middle Aged , Women , Anthropometry , Electromyography , Mastication , Masticatory Muscles , Muscles
Fisioter. Mov. (Online) ; 36: e36103, 2023. tab, graf
Article in English | LILACS | ID: biblio-1421464


Abstract Introduction Chronic obstructive pulmonary disease (COPD) is characterized by limited airflow associated with inflammatory response and systemic manifestations, such as dyspnea, as well as physical inactivity and intolerance to exercise. The sum of these changes can lead to peripheral muscle fatigue and exert an impact on the performance of activities of daily living (ADL). Objective To investigate the possible association between peripheral muscle fatigue and performance on ADL in individuals with COPD, and to compare the results to those of healthy age-matched individuals. Methods Individuals with a diagnosis of COPD and healthy volunteers aged 60 years or older were submitted to evaluations of peripheral muscle fatigue (using surface electromyography) and performance on the Glittre-ADL test. Results Nine individuals with COPD and ten controls were evaluated. Median isometric quadriceps contraction time was 72 [38] and 56 [51] seconds, respectively. Execution time on the ADL test was 6.1 [4] and 3.6 [1.3] minutes for COPD and control group respectively, with a significant difference between groups (p < 0.05). However, no significant correlation was found between the evaluations. Conclusion No association was found between quadriceps muscle fatigue and performance on ADL in the sample studied. In the intergroup comparison, the individuals with COPD exhibited worse ADL time execution, but no significant difference was found regarding quadriceps muscle fatigue.

Resumo Introdução A doença pulmonar obstrutiva crônica (DPOC) é caracterizada por fluxo aéreo limitado associado à resposta inflamatória e manifestações sistêmicas, como dispneia, além de inatividade física e intolerância ao exercício. A soma dessas alterações pode levar à fadiga muscular periférica e exercer impacto no desempenho das atividades de vida diária (AVD). Objetivo Investigar a possível associação entre fadiga muscular periférica e desempenho em AVD em indivíduos com DPOC e comparar os resultados com indivíduos saudáveis da mesma faixa etária. Métodos Indivíduos com diagnóstico de DPOC e voluntários saudáveis com idade igual ou superior a 60 anos foram submetidos a avaliações de fadiga muscular periférica (por meio de eletromiografia de superfície) e desempenho no teste Glittre-ADL. Resultados Foram avaliados nove indivíduos com DPOC e dez controles. O tempo médio de contração isométrica do quadríceps foi de 72 [38] e 56 [51] segundos, respectivamente. O tempo de execução do teste de AVD foi de 6,18 [4,09] e 3,67 [1,3] minutos para DPOC e grupo controle, respectivamente, com diferença significativa entre os grupos (p < 0,05). No entanto não encontrou-se correlação significativa entre as avaliações. Conclusão Não encontrou-se associação entre a fadiga muscular do quadríceps e o desempenho nas AVD na amostra estudada. Na comparação intergrupos, os indivíduos com DPOC apresentaram pior tempo de execução das AVD, mas não encontrou-se diferença significativa em relação à fadiga muscular do quadríceps.

Humans , Middle Aged , Aged , Aged, 80 and over , Activities of Daily Living , Muscle Fatigue , Pulmonary Disease, Chronic Obstructive , Quadriceps Muscle , Electromyography , Healthy Volunteers
Braz. j. oral sci ; 22: e238358, Jan.-Dec. 2023. ilus
Article in English | LILACS, BBO | ID: biblio-1424958


Aim: The study aimed to evaluate the accuracy of the maximum bilateral molar bite force and the Root Mean Square (RMS) Electromyography (EMG) index of the masticatory muscles in the maximum bilateral molar bite (MMBMax) of women with myogenic Temporomandibular Disorder (TMD) and asymptomatic. Methods: This is a cross-sectional study, composed of 86 women allocated to the TMD Group (n=43) and Control Group (n=43) diagnosis through the Diagnostic Criteria for Temporomandibular Disorders. The maximum bilateral molar bite force was evaluated using a bite dynamometer and the RMS EMG index of the masticatory muscles (anterior temporalis, masseter) during 5 seconds of the MMBMax task. Student t-test was used for data comparison between accuracy of the bite force and RMS EMG of masticatory muscles during the MMBMax. Results: The maximum bilateral molar bite force showed high accuracy (AUC=0.99) for the diagnosis of women with myogenic TMD and asymptomatic women, and the RMS EMG index evaluated during the MMBMax showed a moderate level of accuracy for all masticatory muscles (AUC=0.70 to 0.75). Conclusion: The bilateral bite dynamometer with a surface EMG during bilateral bite can be used to diagnose TMD in young women

Humans , Female , Adolescent , Adult , Middle Aged , Bite Force , Temporomandibular Joint Disorders/diagnostic imaging , Electromyography , Masticatory Muscles
Biomédica (Bogotá) ; 42(4): 650-664, oct.-dic. 2022. tab, graf
Article in Spanish | LILACS | ID: biblio-1420313


Introducción. La disfagia se define como la dificultad para movilizar la comida desde la boca hasta el estómago. La prueba diagnóstica para esta condición es la videofluoroscopia, la cual no es totalmente inocua pues utiliza radiación ionizante. La electromiografía de superficie registra la actividad eléctrica de los músculos de manera no invasiva, por lo que puede considerarse como una alternativa para evaluar la deglución y estudiar la disfagia. Objetivo. Evaluar la relación entre los tiempos relativos de activación de los músculos implicados en la fase oral y faríngea de la deglución, con los movimientos registrados durante la videofluoroscopia. Materiales y métodos. Se analizaron las señales de la electromiografía de superficie de 10 pacientes neurológicos con síntomas de disfagia, captadas en forma simultánea con la videofluoroscopia. Se suministraron 5 ml de yogur y 10 ml de agua, y 3 g de galleta. Se estudiaron bilateralmente los grupos musculares maseteros, suprahioideos e infrahioideos. Se analizó el paso del bolo por la línea mandibular, las valleculas y el músculo cricofaríngeo, correlacionándolo con el tiempo inicial y el final de la activación de cada uno de los grupos musculares. Resultados. El tiempo promedio de la fase faríngea fue de 0,89 ± 0,12 s. En la mayoría de los casos, hubo activación muscular antes del paso por la línea mandibular y las valleculas. La terminación de la actividad muscular parece corresponder al momento en que se completa el paso del bolo alimenticio por el músculo cricofaríngeo. Conclusión. Se determinaron los tiempos de actividad muscular, la duración de la fase faríngea y la secuencia de la activación de los grupos musculares involucrados en la deglución, mediante electromiografía de superficie, validada con la videofluoroscopia.

Introduction: Dysphagia is defined as the difficulty in transporting food and liquids from the mouth to the stomach. The gold standard to diagnose this condition is the videofluoroscopic swallowing study. However, it exposes patients to ionizing radiation. Surface electromyography is a non-radioactive alternative for dysphagia evaluation that records muscle electrical activity during swallowing. Objective: To evaluate the relationship between the relative activation times of the muscles involved in the oral and pharyngeal phases of swallowing and the kinematic events detected in the videofluoroscopy. Materials and methods: Electromiographic signals from ten patients with neurological involvement who presented symptoms of dysphagia were analyzed simultaneously with videofluoroscopy. Patients were given 5 ml of yogurt, 10 ml of water, and 3 g of crackers. Masseter, suprahyoid, and infrahyoid muscle groups were studied bilaterally. The bolus transit through the mandibular line, vallecula, and the cricopharyngeus muscle was analyzed in relation to the onset and offset times of each muscle group activation. Results: The average time of the pharyngeal phase was 0.89 ± 0.12 s. Muscle activation was mostly observed prior to the bolus transit through the mandibular line and vallecula. The end of the muscle activity suggested that the passage of the bolus through the cricopharyngeus muscle was almost complete. Conclusion: The muscle activity times, duration of the pharyngeal phase, and sequence of the muscle groups involved in swallowing were determined using sEMG validated with the videofluoroscopic swallowing study.

Deglutition Disorders , Neurologic Manifestations , Parkinson Disease , Signal Processing, Computer-Assisted , Electromyography , Multiple Sclerosis
Rev. Univ. Ind. Santander, Salud ; 54: e600, Dec. 2022. tab
Article in Spanish | LILACS | ID: biblio-1407042


Resumen Introducción: La musculatura del core involucra a todos los grupos musculares ubicados en la zona media del cuerpo. La metodología clínica de elección para el registro y análisis de su actividad bioeléctrica es la electromiografía superficial (sEMG), metodología clínica para el registro y posterior análisis de las actividades bioeléctricas del músculo esquelético. Objetivo: El objetivo de esta investigación es determinar si existen diferencias de actividad electromiográfica en la musculatura del recto abdominal y oblicuo externo entre practicantes de musculación y practicantes de calistenia. Metodología: El estudio es de tipo comparativo, de diseño no experimental, transversal de enfoque cuantitativo en una muestra de 20 sujetos; 10 practicantes de calistenia y 10 que entrenan con ejercicios de musculación clásicos. Resultados: Los ejercicios que tuvieron mayor respuesta electromiográfica fueron abdominal en suspensión y abdominal inclinado. Conclusiones: La calistenia es una alternativa viable para la activación muscular a nivel del Core.

Abstract Introduction: The Core musculature involves all the muscle groups located in the middle area of the body whose activity can be measured using superficial electromyography (sEMG), a clinical methodology for recording and subsequent analysis of skeletal muscle bioelectric activities. Objectives: The objective of this research is to determine if there are differences in electromyographic activity in the muscles of the rectus abdominis and external oblique between bodybuilding practitioners and calisthenics practitioners. Methodology: A comparative study, non-experimental design, cross-sectional with a quantitative approach in a sample of 20 subjects; 10 calisthenics practitioners and 10 who train with classic bodybuilding exercises. Results: The exercises with the greatest electromyographic response were abdominal in suspension and abdominal incline. Conclusions: Calisthenics is a viable alternative for muscle activation at the Core level.

Humans , Male , Female , Adult , Electromyography , Resistance Training , Abdominal Core , Exercise , Mentoring , Gymnastics
J. oral res. (Impresa) ; 11(3): 1-10, jun. 30, 2022. ilus, tab
Article in English | LILACS | ID: biblio-1427370


Introduction: The objective of this study was to explore the electrical activity of the superficial muscles of mastication required to exert unilateral maximum bite force in subjects with different body mass index. Material and Methods: A cross-sectional observational study was conducted with a sample of 21 participants with an average age of 22.9 ± 3.5 years who were classified according to their body mass index, forming three study groups: normal weight (18.5-24.9), overweight (25-29.9) and obesity (≥30), with seven participants each. Through surface electromyography, the superficial muscles of mastication during right and left maximum bite force were evaluated. Results: No statistically significant differences in the maximum bite force were observed between the study groups. The data obtained from the electromyographic analysis of the superficial muscles of mastication demonstrate a trend indicating that subjects with a normal body mass index similarly activate the muscles on each side when performing a maximum bite force on a particular side, while overweight or obese subjects demonstrated significantly greater activation of the temporalis muscle associated with the side where the maximal bite force is performed. Conclusion: Our findings suggest that the maximum bite force is not influenced by body mass index and that during the performance of a maximum bite force subjects with increased body mass index present a greater activation of the temporalis muscle associated with the side where the maximum bite force was performed.

Introducción: El objetivo de este estudio fue explorar la actividad eléctrica de los músculos superficiales de la masticación, necesarios para ejercer la máxima fuerza de mordida unilateral, en sujetos con diferente índice de masa corporal. Material y Métodos: Se realizó un estudio observacional de corte transversal con una muestra de 21 participantes con una edad promedio de 22.9 ± 3.5 años, quienes fueron clasificados de acuerdo a su índice de masa corporal, formando tres grupos de estudio: peso normal (18,5-24,9), sobrepeso (25,0-29,9) y obesidad (≥30.0), con siete participantes cada uno. La electromiografía de superficie evaluó los músculos superficiales de la masticación durante la fuerza de mordida máxima derecha e izquierda. Resultados: No se observaron diferencias estadísticamente significativas en la fuerza de mordida máxima entre los grupos de estudio. Los datos obtenidos del análisis electromiográfico de los músculos superficiales de la masticación demuestran una tendencia que indica que los sujetos con un índice de masa corporal normal activan de manera similar los músculos de cada lado cuando ejercen la fuerza de mordida máxima en un lado en particular. mientras que los sujetos con sobrepeso u obesos demostraron una activación significativamente mayor del músculo temporal asociado con el lado donde se realiza la fuerza máxima de mordida. Conclusión: Nuestros hallazgos sugieren que la fuerza de mordida máxima no está influenciada por el índice de masa corporal y que durante la realización de una fuerza de mordida máxima los sujetos con índice de masa corporal aumentado presentan una mayor activación del músculo temporal asociado al lado donde se realizó la fuerza de mordida máxima.

Humans , Male , Female , Adolescent , Adult , Young Adult , Bite Force , Body Weight/physiology , Mastication/physiology , Masticatory Muscles/physiology , Temporal Muscle , Body Mass Index , Electromyography/methods
Int. j. morphol ; 40(3): 728-734, jun. 2022. ilus, tab
Article in English | LILACS-Express | LILACS | ID: biblio-1385653


SUMMARY: The main objective of this study was to analyze by real-time quantitative polymerase chain reaction (RT-qPCR) the expression patterns of the myosin heavy chain (MHC) isoforms (MHC-I, MHC-IIa, MHC-IIx) in the sphenomandibularis portion of the temporalis muscle. We expected to find differences between the sphenomandibularis and the other portions of the temporalis that could be related to the functional characteristics of the sphenomandibularis identified by electromyography. We dissected the right temporalis muscle of ten adult human individuals (five men and five women). Samples of the anterior and posterior temporalis and of the sphenomandibularis portion were obtained from each dissected muscle. These samples were analyzed by RT-qPCR to determine the percentages of expression of the MHC-I, MHC-IIa and MHC-IIx isoforms. No significant differences were identified between the anterior and the posterior temporalis in the expression patterns of the MHC-I, MHC-IIa and MHC-IIx isoforms. However, there were significant differences between the sphenomandibularis and the anterior temporalis. Specifically, the sphenomandibularis portion had a higher percentage of expression of the MHC-I isoform (P=0.04) and a lower percentage of expression of the MHC-IIx isoform (P=0.003). The pattern of expression that we observed in the sphenomandibularis reflects a greater resistance to fatigue, a lower contraction speed, and a lower capacity of force generation in the sphenomandibularis compared to the anterior temporalis. These characteristics are consistent with electromyographic findings on the functional differences between these two portions.

RESUMEN: El principal objetivo de este estudio fue analizar mediante real-time quantitative polymerase chain reaction (RT-qPCR) los patrones de expresión de las isoformas de la cadena pesada de la miosina (MHC-I, MHC-IIa y MHC-IIx) en la porción esfenomandibular del músculo temporal. Se esperó encontrar diferencias entre el esfenomandibular y las otras porciones del músculo temporal que se pudieran relacionar con las características funcionales del esfenomandibular, identificadas mediante electromiografía. Para obtener estos resultados, se diseccionó el músculo temporal derecho en diez humanos adultos (cinco hombres y cinco mujeres) y se obtuvieron muestras de la porción anterior y posterior del músculo temporal y de su porción esfenomandibular. Estas muestras fueron analizadas mediante RT-qPCR para determinar los porcentajes de expresión de las isoformas MHC-I, MHC- IIa y MHC-IIx. No se identificaron diferencias significativas de los patrones de expresión entre la porción anterior y la porción posterior del músculo temporal, pero sí que se observaron diferencias significativas entre la porción anterior del músculo temporal y su porción esfenomandibular. Concretamente, la porción esfenomandibular presentó un mayor porcentaje de expresión de la isoforma MHC-I (P=0.04) y un menor porcentaje de expresión de la isoforma MHC-IIx (P=0.003). El patrón de expresión que hemos observado en la porción esfenomandibular del músculo temporal refleja una mayor resistencia a la fatiga, una velocidad de contracción más lenta y una menor capacidad de generar fuerza si se compara esta porción con la porción anterior del músclo temporal. Estas características son consistentes con las diferencias funcionales que presentan estas dos porciones, que han sido descritas mediante electromiografía.

Humans , Male , Female , Adult , Middle Aged , Aged , Aged, 80 and over , Temporal Muscle/metabolism , Myosin Heavy Chains/metabolism , Sphenoid Bone , RNA, Messenger/metabolism , Immunohistochemistry , Protein Isoforms , Electromyography , Real-Time Polymerase Chain Reaction
Int. j. morphol ; 40(3): 584-594, jun. 2022. ilus, tab
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1385683


RESUMEN: Se ha postulado que la posición postural mandibular (PPM) no presentaría la menor actividad electromiográfica (EMG) de los músculos masetero y temporal, y que esta menor actividad se encontraría en una apertura mayor. El objetivo de este estudio fue analizar la PPM en pacientes con diferentes relaciones oclusales y según tipo de método de posicionamiento, relacionándolo con la actividad EMG de los músculos Masetero y Temporal, además del registro de la actividad EMG en diferentes aperturas orales. Se analizó una muestra de 25 adultos de 18 a 28 años. Estos fueron clasificados según su sexo y clasificación de Angle. Se realizaron simultáneamente registros de EMG de superficie -masetero y porción anterior del temporal- y de EMA -posición de la mandíbula respecto al maxilar obteniendo distancia y ángulo- en diferentes posiciones mandibulares: PPM-considerando método sin comando y de deglución- y apertura gradual hasta alcanzar la máxima apertura. Se realizó un análisis estadístico descriptivo. La menor PPM obtenida fue de 1,0 ± 0,6 mm en mujeres Clase III y utilizando la técnica sin comando; el mayor fue de 2,5 ± 0,2 mm en mujeres Clase II y utilizando la técnica de deglución. La apertura angular presentó menor variabilidad que las distancias lineales. La actividad de los músculos Maseteros derecho e izquierdo presentaron valores similares entre sí, al igual que en los rangos de apertura hasta 30 mm en hombres y mujeres y en las diferentes relaciones oclusales. La actividad de los Temporales para hombres y mujeres y en las diferentes relaciones oclusales mostraron variaciones importantes entre derecha e izquierda y en los diferentes grados de apertura. La técnica presentada permitió el estudio de la dimensión vertical y aperturas orales a través de EMA y EMG.

SUMMARY: It has been postulated that the mandibular postural position (MPP) could not present the lower electromyographic activity (EMG) of the Masseter and Temporal muscles, and that the lower activity could be found in a larger opening. The objective of this study was to analyze the PPM in patients with different occlusal relationships and according to the positioning method, relating it to the EMG activity of the Masseter and Temporal muscles, in addition to recording the EMG activity in different oral openings. A sample of 25 adults aged 18 to 28 years was analyzed. Participants were classified according to their sex and Angle classification. Simultaneous recordings of surface EMG -Masseter and anterior portion of the Temporal- and EMA -position of the Mandible with respect to the Maxilla obtaining distance and angle- were performed in different mandibular positions: PPM-considering the method "without command" and "swallowing"- and gradual opening until the maximum opening is reached. A descriptive statistical analysis was performed. The lowest PPM obtained was 1.0 ± 0.6 mm in Class III women and using the "without command" method; the largest was 2.5 ± 0.2 mm in Class II women and using the "swallowing" method. The angular opening presented less variability than the linear distances. The activity of the right and left masseter muscles presented similar values, as well as in the opening ranges up to 30 mm in men and women and in the different occlusal relationships. The activity of the Temporals for men and women and in the different occlusal relationships showed important variations between right and left and in the different degrees of opening. The presented technique allowed the study of the vertical dimension and oral openings through EMA and EMG.

Humans , Male , Female , Adolescent , Adult , Young Adult , Vertical Dimension , Electromyography , Malocclusion , Mandible/anatomy & histology , Cross-Sectional Studies , Dental Occlusion , Masticatory Muscles/physiology
Distúrb. comun ; 34(2): e52916, jun. 2022. ilus, tab
Article in Portuguese | LILACS | ID: biblio-1396831


Objetivo: Correlacionar os dados acústicos da ausculta cervical com a atividade elétrica dos músculos envolvidos na fase faríngea da deglutição. Métodos: Trata-se de um estudo observacional, transversal, de abordagem quantitativa, aprovado em janeiro pelo CEP/UFSCPA (número 1.389.050). Todos os participantes do estudo assinaram o termo de consentimento livre e esclarecido. A fase faríngea da deglutição foi avaliada por meio de ausculta cervical e eletromiografia de superfície. Os indivíduos ingeriram 90 ml de água. Os dados da ausculta foram transferidos para o DeglutiSom® software, a duração e amplitude da atividade eletromiográfica foram mensuradas durante a deglutição com aparelho de eletromiografia de superfície Miotec®. O nível de significância adotado foi de 5%. Resultados:Cinquenta e sete mulheres participaram deste estudo. A média de idade foi de 23,4 anos. Ressalta-se que quanto maior a frequência média do pico da ausculta, menor é a média do pico do músculo supra-hióideo e quanto maior a intensidade, maior é o pico, assim como a média dos picos supra-hióideos. Foi possível demonstrar que o pico de atividade do músculo supra-hióideo foi significativamente maior do que o pico de atividade do músculo infra-hióideo para a deglutição de 90 ml de água. Conclusão:Os parâmetros acústicos da deglutição em indivíduos saudáveis estão correlacionados com a atividade elétrica dos músculos envolvidos na fase faríngea da deglutição.

Objective: Correlate the acoustic data of cervical auscultation to the electrical activity of the muscles involved in the pharyngeal phase of swallowing. Methods: This is an observational, cross-sectional study involving a quantitative approach and was approved on January by CEP/UFSCPA (number 1.389.050). All participants of the study signed an informed consent form. The pharyngeal phase of swallowing was assessed by employing auscultation and surface electromyography. Individuals ingested 90 ml of water. The auscultation data were transferred to DeglutiSom® software, the duration and amplitude of electromyographic activity was measured during swallowing using a Miotec® surface electromyography device. The level of significance adopted was 5%. Results: Fifty-seven women participated in this study. The average age was 23.4 years on average. It must be highlighted that the greater the average peak frequency of auscultation, lower was the average peak of the suprahyoid muscle and the greater the intensity, the greater was the peak, as well as the average of the suprahyoid peaks. It was possible to demonstrate that the peak of suprahyoid muscle activity was significantly higher than the peak of infra hyoid muscle activity for swallowing 90 ml of water. Conclusion: The acoustic swallowing parameters in healthy individuals are correlated with the electrical activity of muscles involved in the pharyngeal phase of swallowing.

Objetivo: Correlacionar los datos acústicos de la auscultación cervical con la actividad eléctrica de los músculos involucrados en la fase faríngea de la deglución. Métodos: Se trata de un estudio observacional, transversal, de abordaje cuantitativo y aprobado en enero por CEP/UFSCPA (número 1.389.050). Todos los participantes del estudio firmaron un formulario de consentimiento informado. La fase faríngea de la deglución se evaluó mediante auscultación y electromiografía de superficie. Los individuos ingirieron 90 ml de agua. Los datos de auscultación fueron cargados em el software DeglutiSom®, la duración y la amplitud de la actividad electromiográfica se midió durante la deglución utilizando un dispositivo de electromiografía de superficie Miotec®. El nivel de significancia adoptado fue del 5%. Resultados: Cincuenta y siete mujeres participaron en este estudio. La edad promedio fue 23,4 años. Cabe destacar que a mayor frecuencia de pico promedio de auscultación, menor fue el pico promedio del músculo suprahioideo y a mayor intensidad, mayor fue el pico, así como el promedio de los picos suprahioideos. Fue posible demostrar que el pico de actividad del músculo suprahioideo era significativamente más alto que el pico de actividad del músculo infrahioideo para tragar 90 ml de agua. Conclusión: Los parámetros de deglución acústica en individuos sanos se correlacionan con la actividad eléctrica de los músculos involucrados en la fase faríngea de la deglución.

Humans , Female , Adolescent , Adult , Middle Aged , Auscultation , Deglutition/physiology , Electromyography , Correlation of Data , Pharynx , Cross-Sectional Studies , Deglutition
ABCS health sci ; 47: e022226, 06 abr. 2022. ilus, tab, graf
Article in English | LILACS | ID: biblio-1398289


INTRODUCTION: About 10 million people have low back pain (LBP) disability in Brazil. Several therapies are used to treat this condition, such as kinesiotherapy, manual therapy (MT), and photobiomodulation (PBM). Although the use of these methods in LBP has been investigated, studies evaluating the efficacy of the association between these techniques are still needed. OBJECTIVE: To evaluate the activation of the lumbar region muscles by PBM or MT associated with kinesiotherapy for the treatment of LBP. METHODS: Twenty individuals with chronic LBP were randomlydivided into two groups. The first group (MT) received vertebral mobilization associated with a kinesiotherapy exercise program. The second group (830nm-PBM) received PBM associated with the exercise program, twice a week for 8 weeks. Evaluation of pain perceived was performed by the visual analogic scale (VAS), lumbar disability by the Oswestry questionnaire, muscle strength by strain gauge, and activation through surface electromyography (EMG). Data were collected before and after the treatment. EMG data was analyzed by MatLab®. The ANOVA two-way test was used (degree of significance p≤0.05), and the size of the effect by the Hedge test. RESULTS: Considering pain, the two groups presented a significant result (p<0.05). In muscle activation, only the multifidus was different during the side bridge (p<0.05) when compared intragroup. None of the variables were different when evaluating intergroup. CONCLUSION: Both MT and PBM associated with kinesiotherapy for 8 weeks are effective in reducing pain, and improving motor control and stability of the lumbar spine in patients with chronic LBP.

Humans , Male , Female , Adult , Middle Aged , Young Adult , Low Back Pain/radiotherapy , Low Back Pain/therapy , Musculoskeletal Manipulations , Low-Level Light Therapy , Electromyography
Distúrb. comun ; 34(1): e53050, mar. 2022. ilus, tab
Article in Portuguese | LILACS | ID: biblio-1396344


Introdução: A mastigação tem uma importância significativa para o desenvolvimento das estruturas do Sistema Estomatognático (SE), sendo esta aperfeiçoada no decorrer da vida. A eletromiografia de superfície destaca-se como uma importante ferramenta de avaliação capaz de quantificar a atividade elétrica dos músculos mastigatórios, sendo uma forma de caracterizar o comportamento dessa função estomatognática. Observando a complexidade e importância da mastigação, torna-se importante conhecer melhor as modificações desta função no decorrer dos ciclos de vida. Objetivo: O objetivo do estudo foi realizar análise eletromiográfica dos músculos da mastigação em indivíduos sem queixas orofaciais representantes dos ciclos da infância, adolescência, fase adulta e senescência. Método: A amostra foi composta por 120 voluntários de ambos os sexos, distribuídos em quatro grupos de acordo com a faixa de idade. Os voluntários foram submetidos à avaliação da mastigação por meio da eletromiografia de superfície durante o repouso, contração voluntária máxima, mastigações unilaterais direita e esquerda e mastigação habitual; bem como a verificação da força de mordida entre os dentes incisivos centrais, molares do lado direito e molares do lado esquerdo. Realizou-se, ainda, a tomada de medidas antropométricas faciais das hemifaces direta e esquerda dos voluntários. Resultados: Os resultados apontaram comportamentos morfológicos e funcionais distintos entre os grupos estudados, bem como a influência da variável sexo nas respostas eletrofisiológicas da função mastigatória. Conclusão: foi verificado que o comportamento mastigatório variou segundo a idade e o sexo, apontando uma tendência de correlação entre os componetes anatômicos e funcionais envolvidos nessa função estomatognática.

Introduction: Chewing is of significant importance for the development of the structures of the Stomatognathic System (SE), which is improved throughout life. Surface electromyography stands out as an important assessment tool capable of quantifying the electrical activity of the masticatory muscles, being a way to characterize the behavior of this stomatognathic function. Observing the complexity and importance of chewing, it is important to better understand the changes in this function during the life cycles. Objective: The objective of the study was to perform an electromyographic analysis of the muscles of mastication in individuals without orofacial complaints representing the cycles of childhood, adolescence, adulthood and senescence. Method: The sample consisted of 120 volunteers of both sexes, distributed in four groups according to the age group. The volunteers underwent chewing assessment by means of surface electromyography during rest, maximum voluntary contraction, unilateral right and left chewing and habitual chewing; as well as the verification of the bite force between the central incisor teeth, molars on the right side and molars on the left side. Facial anthropometric measurements of the direct and left hemifaces of the volunteers were also taken. Results: The results showed distinct morphological and functional behaviors between the groups studied, as well as the influence of the gender variable on the electrophysiological responses of the masticatory function. Conclusion: it was found that the masticatory behavior varied according to age and sex, pointing to a trend of correlation between the anatomical and functional components involved in this stomatognathic function.

Introducción: La masticación es de gran importancia para el desarrollo de las estructuras del Sistema Estomatognático (SE), que se mejora a lo largo de la vida. La electromiografía de superficie se destaca como una importante herramienta de evaluación capaz de cuantificar la actividad eléctrica de los músculos masticatorios, siendo una forma de caracterizar el comportamiento de esta función estomatognática. Observando la complejidad de esta función, es importante conocer mejor los cambios de esta función durante los ciclos de vida. Objetivo: El objetivo del estudio fue realizar un análisis electromiográfico de los músculos de la masticación en individuos sin quejas orofaciales representando los ciclos de niñez, adolescencia, adultez y senescencia. Método: La muestra estuvo formada por 120 voluntarios de ambos sexos, distribuidos en cuatro grupos según el grupo de edad. Los voluntarios fueron sometidos a valoración masticatoria mediante electromiografía de superficie en reposo, máxima contracción voluntaria, masticación unilateral derecha e izquierda y masticación habitual; así como la verificación de la fuerza de mordida entre los incisivos centrales, molares del lado derecho y molares del lado izquierdo. También se tomaron medidas antropométricas faciales de los hemifaces directo e izquierdo de los voluntarios. Resultados: Los resultados mostraron distintos comportamientos morfológicos y funcionales entre los grupos estudiados, así como la influencia de la variable género en las respuestas electrofisiológicas de la función masticatoria. Conclusión: se encontró que el comportamiento masticatorio varió según la edad y el sexo, apuntando a una tendencia de correlación entre los componentes anatómicos y funcionales involucrados en esta función estomatognática.

Humans , Male , Female , Child, Preschool , Child , Adolescent , Adult , Middle Aged , Aged , Aged, 80 and over , Age Factors , Electromyography , Masticatory Muscles/physiology , Bite Force , Cross-Sectional Studies
Distúrb. comun ; 34(1): e51813, mar. 2022. ilus, tab
Article in Portuguese | LILACS | ID: biblio-1396521


Introdução: A eletromiografia de superfície (EMGs) é um exame objetivo, indolor, não invasivo e de fácil aplicação utilizado para avaliar as atividades elétricas de determinado músculo ou grupo muscular durante a máxima contração voluntária, repouso e dinâmica funcional. Objetivo: Comparar a variação do potencial elétrico dos músculos masseteres entre o repouso e máxima contração voluntária em indivíduos com faixas etárias diferentes. Método: A pesquisa foi aprovada em comitê de ética e executada na Clínica Escola do Departamento de Fonoaudiologia da Universidade Federal de Sergipe obedecendo aos rigores éticos e de biossegurança. A amostra foi composta por 26 adultos sem queixas orofaciais, sexo masculino e idade variando entre 26 e 42 anos, divididos em Grupo 1 e Grupo 2, os quais assinaram um termo de consentimento livre e esclarecido concordando com a participação na pesquisa. Os voluntários foram submetidos à avaliação eletromiográfica dos músculos masseteres durante o repouso e máxima contração voluntária. Resultados: Houve uma diminuição da atividade elétrica do masseter quando se comparou o G1 com o G2, porém não foi observada uma linearidade desse declínio ao analisar o universo estudado. Por isso, deve-se levar em consideração que o envelhecimento é um processo fisiológico particular de cada ser, sendo influenciado por múltiplos fatores intrínsecos e extrínsecos ao organismo. Observou-se, também, que no repouso nenhum indivíduo teve absolutamente 0 nos seus registros eletromiográficos, caracterizando um estado basal de atividade elétrica para garantia do tônus. Conclusão: Foi verificado que os voluntários com 30 anos ou mais apresentaram um declínio nos potenciais mioelétricos e, possivelmente, um déficit de força associado.

Introduction: Surface electromyography (EMGs) is an objective, painless, non-invasive and easily applied test used to assess the electrical activities of a particular muscle or muscle group during maximum voluntary contraction, rest and functional dynamics. Objective: Compare the variation in the electrical potential of the masseter muscles between rest and maximum voluntary contraction in individuals with different age groups. Method: The research was approved by the ethics committee and carried out at the Clínica Escola of the department of Speech, Language and Hearing Sciences at the Federal University of Sergipe, obeying ethical and biosafety rigors. The sample consisted of 26 adults without orofacial complaints, male with age from 26 to 42 years old, divided into Group 1 and Group 2, who signed a consent form agreeing to participate in the research. The volunteers underwent electromyographic evaluation of the masseter muscles during rest and maximum voluntary contraction. Results: There was a decrease in the electrical activity of the masseter when comparing G1 to G2; however, there was no linearity of this decline when analyzing the universe studied. Therefore, it must be taken into account that aging is a particular physiological process of each individual, being influenced by multiple factors, intrinsic and extrinsic to the organism. It was also observed at rest, no individual had absolutely 0 in their electromyographic records, characterizing a baseline state of electrical activity to guarantee tone. Conclusion: It was found that volunteers aged 30 years or more showed a decline in myoelectric potentials and possibly an associated strength deficit.

Introducción: Electromiografía de superficie (EMG) es una prueba objetiva, indolora, no invasiva y de fácil aplicación que se utiliza para evaluar actividades eléctricas de un músculo o grupo muscular en particular durante la contracción voluntaria máxima, el reposo y la dinámica funcional. Objetivo: Comparar la variación del potencial eléctrico de los maseteros entre reposo y contracción voluntaria máxima en individuos de diferentes grupos de edad. Método: La investigación fue aprobada por el comité de ética y realizada en la Clínica Escola del departamento de logopedia de la Universidad Federal de Sergipe obedeciendo rigores éticos y de bioseguridad. La muestra estuvo conformada por 26 adultos sin quejas orofaciales, varones y edades comprendidas entre 26 y 42 años dividido en Grupo 1 y Grupo 2, quienes firmaron formulario de consentimiento aceptando participar en la investigación. Los voluntarios se sometieron a evaluación electromiográfica de los músculos maseteros durante reposo y la máxima contracción voluntaria. Resultados: Hubo disminución en la actividad eléctrica del masetero cuando se comparó G1 con G2, sin embargo no hubo linealidad de esta disminución al analizar el universo estudiado. Por tanto, hay que tener en cuenta que el envejecimiento es proceso fisiológico particular de cada ser, siendo influenciado por múltiples factores intrínsecos y extrínsecos al organismo. También se observó que en reposo ningún individuo tenía absolutamente 0 en sus registros electromiográficos, caracterizando estado basal de actividad eléctrica para garantizar el tono. Conclusión: Se encontró que los voluntarios de 30 años o más mostraron una disminución en los potenciales mioeléctricos y posiblemente un déficit de fuerza asociado.

Humans , Male , Adult , Electric Stimulation , Masseter Muscle/physiology , Muscle Contraction , Cross-Sectional Studies , Electromyography , Masticatory Muscles/physiology
Motriz (Online) ; 28: e10220009221, 2022. graf
Article in English | LILACS | ID: biblio-1351122


Abstract Aim: The present study aimed to compare the strength performance and the neuromuscular activity during one maximum repetition test (1RM), and the maximum voluntary isometric contractions (MVIC) performed with whole-body vibration (WBV), local vibration (LV), and no vibration (NV). Methods: The sample consisted of 15 males, experienced in strength training for at least 6 months, which performed all strength tests in the barbell curl exercise across randomized trials on the following conditions: NV, WBV, and LV. During all tests, the normalized root means square values of the electromyographic signals (EMGRMS) of the biceps brachii and brachioradialis were recorded and compared between the conditions. The one-way ANOVAs with repeated measures were used to compare the results of 1RM and MVIC tests and the normalized EMGRMS between the conditions. When necessary, a post hoc Scott-Knott test was used to identify the differences reported in the ANOVAs. The significance level adopted was α < 0.05. Results: The EMGRMS response of the biceps brachii and brachioradialis muscles during the 1RM and MVIC tests presented significantly higher values at LV compared to WBV, and NV (p < 0.001). The 1RM tests, and the MVIC results were similar between conditions (p = 0.9803; p = 0.061, respectively). Conclusion: These results indicate that the application of MV was not sufficient to increase strength performance.

Humans , Exercise , Muscle Spindles , Electromyography/instrumentation , Resistance Training/instrumentation , Isometric Contraction
Rev. colomb. med. fis. rehabil. (En línea) ; 32(1): 24-35, 2022. tab, graf
Article in Spanish | LILACS, COLNAL | ID: biblio-1451633


Introducción. El estudio de las ondas F evalúa la fisiología normal y anormal del sistema nervioso central y periférico. Sus valores de referencia utilizados actualmente se obtienen según la edad y estatura de poblaciones europeas y estadounidenses y no existe ningún estudio que analice sistemáticamente los valores normales en población colombiana. Objetivo. Analizar los parámetros de ondas F en adultos sanos asistentes a la IPS Rangel de Bogotá para crear una base de datos de valores de referencia que permita determinarycrear una guía de parámetros de normalidad de ondas F en población colombiana adulta sana. Métodos. Estudio observacional desarrollado entre enero de 2019 y diciembre de 2020 y realizado en 53 hombres y mujeres de entre 18 y 60 años asistentes a la IPS Rangel. Se registraron los valores de las ondas F de los nervios mediano, cubital, peroneo y tibial, bilateralmente, según parámetros de latencia mínima, latencia máxima, cronodispersión y persistencia. Los datos recolectados se registraron en una base de datos para su análisis. Resultados. En los miembros superiores se encontraron latencias medias mínimas de 22-26ms y en los inferiores, de 36-46ms. No se encontraron diferencias significativas según la lateralidad y el grupo etario. En el análisis de resultados porsexo se hallaron diferencias significativas entre las latencias mínimas y máximas. La talla se dividió en 3 categorías, encontrándose diferencias significativas entre las latencias distales mínimasy máximas. Conclusiones. El presente estudio determinó los valores de referencia clínicamente útiles para los parámetros de las ondas F en bogotanos sanos de 18 a 60 años de edad para los principales nervios motores, lo cual permite incrementar la calidad de detección de la neuropatía periférica proximal.

Introduction. The study of F waves evaluates the normal and abnormal physiology of the central and peripheral nervous system. Its currently used reference values are obtained according to age and height in European and American populations and there is no study that systematically analyzes the normal values in the Colombian population. Objective. To analyze the F-wave parameters in healthy adults attending the IPS Rangel in Bogotá in order to create a database of reference values to determine and create a guide of F-wave normality parameters in a healthy adult Colombian population. Methods. Observational study developed between January 2019 and December 2020 and conducted in 53 men and women aged 18 to 60 years attending the IPS Rangel. The values of F waves of the median, ulnar, peroneal and tibial nerves were recorded bilaterally, according to parameters of minimum latency, maximum latency, chronodispersion and persistence. The collected data were recorded in a database for analysis. Results. Minimum mean latencies of 22-26ms were found in the upper limbs and 36-46ms in the lower limbs. No significant differences were found according to laterality and age group. In the analysis of results by sex, significant differences were found between minimum and maximum latencies. The height was divided into 3 categories, and significant differences were found between the minimum and maximum distal latencies. Conclusions. The present study determined clinically useful reference values for F-wave parameters in healthy Bogotanos aged 18 to 60 years for the main motor nerves, which allows to increase the quality of detection of proximal peripheral neuropathy.

Humans , Adult , Middle Aged , Electromyography , Colombia
Article in Chinese | WPRIM | ID: wpr-928897


Premature delivery is one of the direct factors that affect the early development and safety of infants. Its direct clinical manifestation is the change of uterine contraction intensity and frequency. Uterine Electrohysterography(EHG) signal collected from the abdomen of pregnant women can accurately and effectively reflect the uterine contraction, which has higher clinical application value than invasive monitoring technology such as intrauterine pressure catheter. Therefore, the research of fetal preterm birth recognition algorithm based on EHG is particularly important for perinatal fetal monitoring. We proposed a convolution neural network(CNN) based on EHG fetal preterm birth recognition algorithm, and a deep CNN model was constructed by combining the Gramian angular difference field(GADF) with the transfer learning technology. The structure of the model was optimized using the clinical measured term-preterm EHG database. The classification accuracy of 94.38% and F1 value of 97.11% were achieved. The experimental results showed that the model constructed in this paper has a certain auxiliary diagnostic value for clinical prediction of premature delivery.

Female , Humans , Infant, Newborn , Pregnancy , Algorithms , Electromyography , Neural Networks, Computer , Premature Birth/diagnosis , Uterine Contraction
Article in Chinese | WPRIM | ID: wpr-928203


At present, fatigue state monitoring of upper limb movement generally relies solely on surface electromyographic signal (sEMG) to identify and classify fatigue, resulting in unstable results and certain limitations. This paper introduces the sEMG signal recognition and motion capture technology into the fatigue state monitoring process and proposes a fatigue analysis method combining an improved EMG fatigue threshold algorithm and biomechanical analysis. In this study, the right upper limb load elbow flexion test was used to simultaneously collect the biceps brachii sEMG signal and upper limb motion capture data, and at the same time the Borg Fatigue Subjective and Self-awareness Scale were used to record the fatigue feelings of the subjects. Then, the fatigue analysis method combining the EMG fatigue threshold algorithm and the biomechanical analysis was combined with four single types: mean power frequency (MPF), spectral moments ratio (SMR), fuzzy approximate entropy (fApEn) and Lempel-Ziv complexity (LZC). The test results of the evaluation index fatigue evaluation method were compared. The test results show that the method in this paper has a recognition rate of 98.6% for the overall fatigue state and 97%, 100%, and 99% for the three states of ease, transition and fatigue, which are more advantageous than other methods. The research results of this paper prove that the method in this paper can effectively prevent secondary injury caused by overtraining during upper limb exercises, and is of great significance for fatigue monitoring.

Humans , Electromyography/methods , Fatigue , Muscle Fatigue , Muscle, Skeletal , Upper Extremity
Article in Chinese | WPRIM | ID: wpr-928201


Lower limb ankle exoskeletons have been used to improve walking efficiency and assist the elderly and patients with motor dysfunction in daily activities or rehabilitation training, while the assistance patterns may influence the wearer's lower limb muscle activities and coordination patterns. In this paper, we aim to evaluate the effects of different ankle exoskeleton assistance patterns on wearer's lower limb muscle activities and coordination patterns. A tethered ankle exoskeleton with nine assistance patterns that combined with differenet actuation timing values and torque magnitude levels was used to assist human walking. Lower limb muscle surface electromyography signals were collected from 7 participants walking on a treadmill at a speed of 1.25 m/s. Results showed that the soleus muscle activities were significantly reduced during assisted walking. In one assistance pattern with peak time in 49% of stride and peak torque at 0.7 N·m/kg, the soleus muscle activity was decreased by (38.5 ± 10.8)%. Compared with actuation timing, the assistance torque magnitude had a more significant influence on soleus muscle activity. In all assistance patterns, the eight lower limb muscle activities could be decomposed to five basic muscle synergies. The muscle synergies changed little under assistance with appropriate actuation timing and torque magnitude. Besides, co-contraction indexs of soleus and tibialis anterior, rectus femoris and semitendinosus under exoskeleton assistance were higher than normal walking. Our results are expected to help to understand how healthy wearers adjust their neuromuscular control mechanisms to adapt to different exoskeleton assistance patterns, and provide reference to select appropriate assistance to improve walking efficiency.

Aged , Humans , Ankle/physiology , Ankle Joint/physiology , Biomechanical Phenomena/physiology , Electromyography , Exoskeleton Device , Gait/physiology , Muscle Contraction , Muscle, Skeletal/physiology , Walking/physiology
Article in Chinese | WPRIM | ID: wpr-939618


The automatic recognition technology of muscle fatigue has widespread application in the field of kinesiology and rehabilitation medicine. In this paper, we used surface electromyography (sEMG) to study the recognition of leg muscle fatigue during circuit resistance training. The purpose of this study was to solve the problem that the sEMG signals have a lot of noise interference and the recognition accuracy of the existing muscle fatigue recognition model is not high enough. First, we proposed an improved wavelet threshold function denoising algorithm to denoise the sEMG signal. Then, we build a muscle fatigue state recognition model based on long short-term memory (LSTM), and used the Holdout method to evaluate the performance of the model. Finally, the denoising effect of the improved wavelet threshold function denoising method proposed in this paper was compared with the denoising effect of the traditional wavelet threshold denoising method. We compared the performance of the proposed muscle fatigue recognition model with that of particle swarm optimization support vector machine (PSO-SVM) and convolutional neural network (CNN). The results showed that the new wavelet threshold function had better denoising performance than hard and soft threshold functions. The accuracy of LSTM network model in identifying muscle fatigue was 4.89% and 2.47% higher than that of PSO-SVM and CNN, respectively. The sEMG signal denoising method and muscle fatigue recognition model proposed in this paper have important implications for monitoring muscle fatigue during rehabilitation training and exercise.

Electromyography , Memory, Short-Term , Muscle Fatigue , Neural Networks, Computer , Recognition, Psychology
Article in Chinese | WPRIM | ID: wpr-935742


Objective: To simulate and evaluate the scraping and grinding work of workers with different spinal anteversion angles, and to explore the effects of different anteversion angles on the erector spinae muscles of scrapers. Methods: In November 2019, 16 male college student volunteers were recruited to simulate workers' scraping and grinding work. The parameters were 25°, 15 times/min, 15°, 30 times/min, 5°, 60 times/min respectively. The surface electromyography (sEMG) was used to collect the electromyographic signals of the erector spinae muscles, and the surface electromyographic characteristics of the erector spinae muscles were evaluated with Borg Scale. Results: There were significant differences between the maximum voluntary contraction percentage (MVE%) of the left and right erector spinae muscles groups in the three groups with different spinal anteversion angles (F(left)=13.41, P(left)<0.001; F(right)=4.74, P(right)=0.005) , and the EMG amplitude was higher at 25°, 15 times/min. At 15°, 30 times/min, MVE% of the left side was significantly higher than that of the right side (t=2.58, P=0.021) . There was significant difference in the mean power frequency (MPF) of the right erector spinae muscle in the three groups (F=9.42, P<0.001) , but there was no significant difference in the MPF of the left erector spinae muscle (F=0.30, P=0.823) . The fitting line showed that the left erector spinae muscle showed a downward trend at 5°, 60 times/min (t=-5.39, P=0.012) . Conclusion: Scrapers are less likely to be fatigued when the posture is 15°, 30 times/min, but they are more likely to be fatigued when working at 5°, 60 times/min.

Humans , Male , Electromyography , Muscle, Skeletal/physiology , Muscles/physiology , Posture/physiology