Human identification based on cranial computed tomography scan: a case report.

Today, there is increasing use of CT scanning on a clinical basis, aiding in the diagnosis of diseases or injuries. This exam also provides important information that allows identification of individuals. This paper reports the use of a CT scan on the skull, taken when the victim was alive, for the positive identification of a victim of a traffic accident in which the fingerprint analysis was impossible. The authors emphasize that the CT scan is a tool primarily used in clinical diagnosis and may contribute significantly to forensic purpose, allowing the exploration of virtual corpses before the classic autopsy. The use of CT scans might increase the quantity and quality of information involved in the death of the person examined.

Relationship between the angle of the coronoid process of the mandible and the electromyographic activity of the temporal muscle in skeletal Class I and III individuals.

The aim of the present study was to verify the relationship between the angle of the coronoid process of the mandible in the latero-lateral direction and electromyographic activity of the anterior part of the temporal muscle in skeletal Class I and III individuals. Forty-five volunteers were assessed subdivided into two groups, according to angle ANB, in Class I and III. Two radiographic examinations were performed, one lateral cephalogram to measure angle ANB and one frontal cephalogram to measure the angle of the coronoid process. The electromyographic examination of the volunteers' temporal muscles was performed. Statistical analysis of the data showed that the relationship between the angle of the coronoid process and the skeletal class was negative for both classes analysed. The relationship between electromyographic activity of the temporal muscle and angle of the coronoid process was negative for Class I individuals. In the Class III group, smaller angles of the coronoid process were related to higher values of electromyographic activity of the temporal muscle. There was no statistically significant difference between the electromyographic activity of the temporal muscle in skeletal Class I and III individuals. Based on the results obtained, it was concluded that there was no influence of the skeletal classes analysed on the angle of the coronoid; the angle of the coronoid process may be influenced by the electromyographic activity of the temporal muscle in the Class III group; the electromyographic activity of the temporal muscle is not influenced by the skeletal class in Class III individuals.

Electromyographic study of stomatognathic system muscles during chewing of different materials.

OBJECTIVE: The aim of this study was to compare the behavior of the major chewing muscles (anterior temporalis, masseter and suprahyoid muscles) by using two commercial chewing gums (A and B) and two insipid materials (cotton ball and Parafilm M) through analysis of electromyographic signals. METHOD: Ten female young adult subjects, aged from 18 to 27 years, with normal occlusion and no history of craniomandibular disorder were studied The masticatory activity was performed with the subjects comfortably sat so that the Frankfurt plane was parallel to the floor. Electromyographic exams were carried out using bipolar surface passive mini-electrodes positioned on the anterior temporalis, masseter, and suprahyoid muscles. The subjects were guided to chew bilaterally and simultaneously each one of the materials, in aleatory sequence. For the study of the masticatory activity the electromyographic signals were processed through rectification, linear envelope and normalization, so that the coefficient of variation obtained from the procedure was comparatively analyzed. All data were submitted to analysis of variance (uni- and multi-varied). RESULTS: The results of this study indicated that the best materials for electromyographic studies on the chewing were Parafilm and cotton ball because they demonstrated the smallest coefficients of variation. CONCLUSION: In addition, Parafilm showed the best palatability. In a general way, these materials are indicated for the accomplishment of electromyographic exams, since they demonstrated a smaller coefficient of variation as compared to the other materials.

Utilização de diferentes estimulações elétricas para o tratamento da dor em mulheres com disfunção temporomandibular / Use of different electrical stimulations for treating pain in women with temporomandibular disorders

OBJETIVO: Analisar a intensidade da dor em indivíduos com disfunção temporomandibular (DTM) tratados com dez sessões de estimulação elétrica nervosa transcutânea (TENS) ou estimulação elétrica de Alta Voltagem (EEAV). MÉTODOS: Foram selecionadas 24 mulheres (22,98±1,86 anos) com diagnóstico de DTM, segundo o Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD), sendo 60 por cento com diagnóstico de DTM do grupo Ia e 40 por cento Ia e IIa. As voluntárias foram divididas em dois grupos denominados grupo TENS (GT) e Grupo Alta Voltagem (GAV). Em ambos os grupos as voluntárias receberam dez aplicações da TENS (10Hz modulada em 50 por cento, 200 µs e intensidade no limiar motor) ou da EEAV (10Hz, pulsos gêmeos com 20µs cada e intervalo 100µs interpulsos gêmeos, 100Volts e pólo positivo) duas vezes por semana por 30 minutos. Para mensurar a intensidade da dor, foi utilizada a escala visual analógica (EVA). Para análise estatística, utilizou-se teste t de Student e análise de regressão linear simples. RESULTADOS: Comparando-se as condições pré e pós TENS observa-se uma redução na intensidade da dor (p<0,05) na maioria das sessões, exceto na sexta, sétima e oitava, enquanto a EEAV reduziu a intensidade da dor (p<0,05) em todas as sessões. Avaliando-se os valores pré-aplicação, os dois recursos diminuíram a intensidade de dor de forma uniforme ao longo das dez sessões (p<0,05). CONCLUSÕES: A TENS e a EEAV promoveram redução da intensidade da dor em mulheres com DTM, sendo a EEAV mais um recurso indicado para o tratamento desses pacientes.

OBJECTIVE: To analyze pain intensity in individuals with temporomandibular disorder (TMD) who were treated with ten sessions of transcutaneous electrical nerve stimulation (TENS) or high voltage electrical stimulation (HVES). METHODS: Twenty-four women (22.98±1.86 years old) with a diagnosis of TMD in accordance with the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) were selected. 60 percent of the subjects had a diagnosis of TMD classified as group Ia and 40 percent as Ia and IIa. They were divided into two groups named the TENS group (TG) and the high voltage group (HVG). Each individual received ten applications of either TENS (10Hz, modulated at 50 percent, 200µs and motor threshold intensity) or HVES (10Hz, twin pulses of 20µs each at intervals of 100µs between the twin pulses, 100volts and positive pole) twice a week for 30 minutes. To measure the pain intensity, a visual analog scale (VAS) was used. Statistical analyses were performed using Student's t test and simple linear regression. RESULTS: Comparison of the pre and post-TENS conditions showed diminished pain intensity (p<0.05) at most sessions except for sessions 6, 7 and 8. In contrast, HVES reduced the pain intensity at all sessions (p<0.05). Evaluation of the pre-application values showed that both treatments decreased the pain intensity uniformly over the ten sessions (p<0.05). CONCLUSIONS: TENS and HVES both promoted reductions in pain intensity in women with TMD. HVES is a therapeutic resource recommended for such patients.

Sinais e sintomas de disfuncao temporomandibular em criancas portadoras de paralisia cerebral / Signs and symptoms of temporomandibular dysfunction in children wit cerebral palsy

O objetivo deste estudo foi analisar os sinais e sintomas de disfuncao temporomandibular em criancas portadoras de paralisia cerebral. Material e metodos: Foram avaliadas 22 criancas entre 5 e 13 anos, sendo 10 portadoras de paralisia cerebral espastica (9,1+-2,64 anos) e 12 normais (7,91+-0,99 anos). Foram colhidas informacoes sobre mastigacao, dor muscular e articular e ruidos articulares. Tambem foi determinado o indice de disfuncao clinica de Helkimo e o grau de espasticidade por meio da Escala de Espasticidade Ashworth Modificada. Resultados: os resultados indicam que nao ha diferenca significativa (p=0,231) na maxima abertura bucal entre os grupos. Contudo, no movimento lateral direito (p=0,001), no movimento lateral esquerdo (p=0,048) e na protusao (p=0,009) observou-se significativa diferenca. Conclusao: muitas criancas com paralisia cerebral nao realizaram o movimento de protrusao (50 por cento) e a lateralidade par um dos lados (40 por cento) , mas a severidade da disfuncao temporomandibular nao esta relacionada com a severidade da espasticidade

Preliminary rapport on head posture and muscle activity in subjects with class I and II.

Forward head posture may cause alterations in the stomatognathic system, including changes in the muscle activity of the masticatory muscles and dental occlusion alterations. Considering the need for further understanding of the relationship between the stomatognathic system and the cervical region, the purpose of this study was to analyse the head posture and the electromyographic (EMG) activity of the anterior portion of temporal and masseter muscles bilaterally among bruxist's subjects with different dental occlusion classifications using the Angle method. The study consisted of 20 female volunteers, between the ages of 17 and 27 years. They were separated into two groups (class I and class II occlusions) according to a dentist-performed evaluation. An assessment of forward head posture was conducted using a photographic technique (angular calculus) combined with a clinical analysis. In the EMG analyses, active differential surface electrodes (Ag) were utilized and were placed bilaterally on the belly of masseter and temporal muscles, perpendicular to the muscles fibres. The EMG signal recorded during bilateral isotonic mastication, was presented using the Root Mean Square and was processed by Matlab software. The results indicated that the EMG responses of temporal and masseter muscles tend to be modified by occlusion alteration class II. Subjects with class II occlusion tended to present more occurrence of forward head posture with alterations in the muscle activity pattern between masseter and temporal muscles.

Avaliação propriocepção do joelho em individuos portadores de disfunção femoropatelar / Evaluation of proprioception on the knee among individuals with patellofemoral dysfunctuion

Avaliar a propriocepcao do joelho de individuos portadores de disfuncao femoropatelar (DFP) e de individuos-controle em dinamometro isocinetico. Metodo: forma selecionados 20 sujeitos do sexo feminino, sendo 10 (22,5 +- 2,3 anos) portadores de DFP unilateral sem sintomatologia dolorosa (grupo DFP) e 10 (21,3 +- 1,7 anos) clinicamente normais (grupo N). As voluntarias, sentadas na cadeira do dinamometro isocinetico e com os olhos vendados, realizaram tres reposicionamentos ativos para tres diferentes angulos-alvo (30, 45 e 60 graus) de flexao do joelho. As variaveis estudads foram o angulo de reposicionamento ativo do joelho e os erros absoluto e relativo em relacao a cada angulo-alvo avaliado. Resultados: o teste t evidenciou que nao houve diferenca significativa na media dos reposicionamentos ativos (P30º=0,33l; P45º=0,39; e P60º=0,96) entre os grupos DFP e controle. Alem disso, a analise de variancia (ANOVA) nao mostrou diferenca significativa, tanto na media do erro absoluto (p=0,66) quanto na media do erro relativo (p=0,81) entre os diferentes angulos-alvo de flexao do joelho. Conclusao: nas condicoes experimentais utilizadas, os dados do presente estudo nao evidenciam deficit proprioceptivo em realacao ao senso de posicao articular entre os grupos DFP e controle

Avaliação da amplitude eletromiográfica do musculo deltoide em diferentes faixas etárias / Eletromyografic evaluation of deltoid muscle in different age groups

O objetivo deste trabalho foi estimar o padrao de ativacao eletromiografica das tres porcoes do musculo deltoide, em diferentes faixas etarias, durante o movimento dinamico de abducao do braco, realizado no plano escapular com variacao da rotacao axial do umero. Participaram dessa pesquisa 20 voluntarias, sedentarias e destras, igualmente divididas em 2 grupos. O grupo 1 com media de idade 24(+-3) anos e o grupo 2 com media de idade de 57(+-10) anos. Os sinais de EMG foram adquiridos com eletrodos ativos duplos diferenciais e frequencia de amostragem de 1 KHz. O sinal EMG bruto foi retificado, os envoltorios lineares foram obtidos pela media movel de 250ms e normalizados pela amplitude media do sinal retificado e pela amplitude de movimento. Para examinar os efeitos da faixa etaria e das porcoes do musculo deltoide, os valores medios dos coeficientes de variacao e os proprios envoltorios de cada uma das porcoes do musculo deltoide foram comparados por meio da analise de variancia de dois fatores ( ANOVA e two-way) e pos teste de Bonferroni, com nivel de significacao de 5 (por cento). Os resultados deste estudo mostram que entre os grupos pesquisados, de diferentes faixas etarias, nao ha diferenca nos envoltorios lineares normalizados e nos valores de coeficientes de variacao das tres porcoes do musculo deltoide. Assim, os resultados indicam que a ativacao eletrica das porcoes do musculo deltoide esta presente durante todoo movimento de abducao, independente da rotacao umeral, e que ha mudancas nas proporcoes de atividade mioeletrica esperadas entre as faixas etarias estudadas

Avaliacao multidimensional da dor em portadores de desordem temporomandibular utilizando uma versao brasileira do questionario McGill de dor / Multidimensional pain evaluation in patients with temporomandibular disorders using brazilian version of the McGill pain questionarie

O objetivo deste estudo foi avaliar, discriminar e comparar a queixa dolorosa de portadores de desordem temporomandibular (DTM), classificados segundo indice clinico de diagnostico, ,utilizando versao brasileira do Questionario McGill de Dor (Br-MPQ). Foram estudados 23 pacientes, sendo 21 mulheres e 2 homens (28 +- 11 anos). Oito voluntarios foram classificados como portadores de DTM moderada e 15 como de severa. Sao apresentadas as distribuicoes das frequencias dos achados do Br-MPQ e os resultados do teste Q-quadrado, com nivel de significancia de 5 (por cento). No grupo DTM severa a articulacao temporomandibular foi anotada como a regiao mais dolorosa, enquanto no grupo DTM moderada foi a cervical (p<0,05). O musculo temporal foi indicado como o mais doloroso por ambos os grupos (p<0,05). Para o padrao temporal da dor, 50 (por cento) do grupo com DTM moderada anotou a carcteristica ritmada, periodica, intermitente, enquanto o grupo DTM severa preferiu o padrao continuo, estavel, constante. A analise da intensidade da dor (PPI) revelou que o grupo DTM severa concentrou as anotacoes em niveis de intensidade menores que o grupo DTM moderada (P<0,05). Os valores medios da intensidade da dor (PRI) foram maiores para a dimensao de palavras mistas em ambos os grupos. Assim, os resultados do Br-MPQ foram capazes de diferenciar o padrao temporal, o local de maior queixa de dor e a intensidade da dor de portadores de DTM classificados por um indice diagnostico. No entanto, o carater afetivo, ligado a memoria e a percepcao das dores relacionadas a essa desordem, foi semelhante entre grupos de estudo, independentemente da severidade

Estudo eletromiografico dos musculos vasto medial obliquo e vasto lateral, no dominio temporal, durante a marcha humana / Electromyographic study of the vastus medialis oblique and vastus lateralis muscles during walking

Ha uma crescente preocupacao com o estudo da articulacao do joelho durante atividade funcionais com a marcha humana, embora haja estudos detalhados extensos sobre essa tematica, nada ha na literatura sobre a analise eletromiografica da articulacao do joelho,associando-a a instabilidade femuro-pastelar. O presente estudo teve por objetivo apresrntar atividade eletromiografica dos musculos vasto medial obliquo e vasto lateral, durante a marcha realizada em aclive e declive. Os resultados, por meio da analise do coeficiente de variacao e correlacao cruzada no dominio temporal, indicaram a existencia de padroes semelhantes para as curvas eletromiograficas medias dos musculos supra citados dos voluntarios.Concluiu-se, portanto, que existe um padrao comum de atividade em voluntarios saudaveis para os musculos vasto medial obliquo e vasto lateral

Electromyographic analysis of the extending muscles of the knee during functional activities.

The purpose of this study is to analyze the behavior of electrical activity of the muscles vastus medialis oblique (VMO), vastus medialis long (VML), and, rectus femoris (RF) during functional activities. The electromyography of the VMO, VML and RF muscles were analyzed in ten healthy volunteers. Signs were collected through superficial electrodes and a electrogoniometer, connected to a signal condition module. The analysis of the results after treating the signals shows us that there is a similar electromyographical behavior in the three studied muscles. Therefore, these discoveries suggest a common electrical behavior pattern especially between VMO and VL muscles in healthy volunteers.

Analise da frequencia mediana do sinal eletromiografico de superficie antes e depois da aplicacao da TENS em individuos com DCM e normais / Frequency Analysis of the surface eletromyographical signal before and after TENS in CMDs and health subjects

Sabendo-se que a dor e a fadiga muscular sao sintomas frequentemente relatados por individuos portadores de desordem craniomandibular (DCM), objetivo desta pesquisa foi avaliar o efeito da estimulacao eletrica nervosa transcutanea(TENS) sobre a frequencia mediana do sinal eletromiografico do M. masseter direito e esquerdo. Para tal, foram selecionados 20 voluntarios do sexo feminino (20-33 anos, x=24,6), sendo 10 com DCM e 10 sem DCM. A TENS (pulso quadratico bifasico simetrico, 150 Hz,20 us, intensidade agradavel, modulacao em frequencia (= 50 por cento) foi aplicada uma vez em ambos os grupos, por 45 min. O exame eletromiografico foi realizado antes e imediatamente apos a aplicacao da TENS. A frequencia mediana do sinal eletromiografico foi obtida por meio da transformada Rapida de Fourier(FFT)e os dados foram analizados pelo Teste t para dados pareados e pelo Teste t para duas amostras independentes. O estudo mostrou que em ambos os grupos a media da frequencia mediana do M. masseter direito e esquerda foi menor apos a aplicacao da TENS. Comparando-se os dois grupos antes da aplicacao da TENS, pode-se observar que, no grupo com DCM, a media da frequencia mediana foi menor que no grupo sem DCM e que essa situacao nao foi revertida apos a aplicacao da TENS. Esses resultados sugerem que apenas uma aplicacao da TENS promove um deslocamento do espectro de frequencia em direcao as baixas frequencias, o que pode ser um indicativo de fadiga M. masseter, tanto no grupo com DCM como no grupo sem DCM

Atividade eletromiografica das porçöes anterior, media e posterior do musculo deltoide na abduçäo do braço

O objetivo deste trabalho foi apresentar uma analise eletromiografica das porcoes anterior, medica e posterior do musculo deltoide de vez voluntarios adultos jovens, do sexo feminino, durante o movimento isotonico de abducao livre realizado nos planos escapular e frontal. Os sinais eletromiograficos de superficie foram adquiridos com eletrodos ativos duplo diferenciais, com ganho total de 3.000 vezes e frequencia de amostragem de 1.000Hz. as amostras foram digitalizadas por uma placa conversora A/D de 12bits. Os resultados mostram que, independe do plano de abducao do ombro, os valores de RMS das porcoes media e posterior nao possuem diferencas estatisticaamente significativas e ambas as porcoes possuem valores de RMS inferiores ao da porcao anterior

Electromyographic analysis of fatigue in temporalis and masseter muscles during continuous chewing.

The aim of this study was to evaluate the electromyographic changes in the anterior temporalis and masseter muscles after fatigue induced by continuous chewing. Surface electrodes were placed bilaterally over the anterior temporalis and masseter muscles of 31 subjects with normal dentition. Recordings were taken every minute from the beginning of chewing to the exact moment the volunteer reported subjective sensation of fatigue in the jaw muscles. The length of endurance period (fatigue threshold) was measured to each subject, as well as the average amplitude and duration of activation phase and duration of relaxation phase through electromyographic recording of each muscle. The average endurance period was about 500 s. No significant change occurred on the average amplitude of activation phase meanwhile the duration of both the activation and relaxation phase diminished after fatigue.

Estudo eletromiográfico comparativo de movimentos de facilitaçäo neuromuscular proprioceptiva com os realizados nos planos sagital / Comparative eletromyographic study of movements of proprioceptive neuromuscular facilitation with the realized in sagittal planes

O objetivo deste estudo foi comparar a atividade eletromiográfica dos músculos semitendinosus (SEMI) e bíceps femuris (caput logum) - (BCCL) aos 30§, 60§ e 90§ de flexão do joelho durante movimentos realizados no plano igual, que caracterizam os padrões do Facilitação Neurouscular Proprieceptiva - FNP (Kabat), e os movimentos realizados no plano sagital comumente indicados para reabilitação e treinamento. Estes movimentos foram realizados com e sem aplicação de resistência mecânica por meio do Sistema de Polias Duplas e os graus foram registrados por eletrogoniômetro. Os padrões de movimento no plano diagonal foram: 1) extensão, abdução, rotação medial do quadril, flexão do joelho, flexão plantar com eversão do tornozelo, flexão e adução dos dedos; 2) extensão, adução e rotação lateral do quadril, com flexão do joelho, flexão plantar com inversão do tornozelo, flexão e adução dos dedos. Em ambos os movimentos o voluntário estava em decúbito dorsal. O movimento realizado no plano sagital foi: flexão do joelho com o voluntário posicionado em decúbito ventral. No delineamento estatístico foi verificado os fatores: movimento; carga: sem (L) e com (C); e ângulo: 30§, 60§ e 90§. Para cada um dos músculos, separadamente, foi efetuada Analise de Variância. A interação entre estes fatores foi detalhada para verificar diferenças entre níveis de um fator em cada nível do outro. Nestes casos, calculou-se a DMS para contrastes entre pares de médias pelo método de TUKEY. Os resultados obtidos foram: Efeito de movimento: (M1= M2) < M3, p

The effect of free isotonic and maximal isometric contraction exercises of the hip adduction on vastus medialis oblique muscle: an electromyographic study.

The purpose of this study was to analyse the activity of the vastus medialis oblique (VMO) muscle electromyographically during free isotonic and maximal isometric contraction of the hip adduction with knee extension performing exercises at sitting and in decubitus lateralis positions. Using a 8 channels Nicolet Electromyograph and Beckman surface mini electrodes, the activity of the vastus medialis oblique muscle was recorded among 15 healthy subjects, aged 19 to 33 years, (mean = 24.4, SD = 4.1) without prior knee and hip joints pathology. The sign was recorded in root mean square (RMS), expressed in microvolts. The data were statistically calculated employing an analysis of variance (ANOVA) and the Tukey test, at 5% of significance. The results showed that the electromyographic (EMG) activity of the vastus medialis oblique muscle was significantly greater in both exercises of maximal contraction when compared with free isotonic at decubitus lateralis. On the other hand, there was no significant difference of the electromyographic activity of the vastus medialis oblique muscle between the two exercises of maximal isometric contraction. These findings, within the experimental conditions used, suggest that prior stages of patellofemoral dysfunction, the exercises of hip adduction with knee extension could be performed isometrically or isotonically, at sitting and in decubitus lateralis positions, depending on the biological conditions of each patient.

Influence of myofunctional therapy on the perioral muscles. Clinical and electromyographic evaluations.

The purpose of this study was to evaluate the influence of oral myofunctional therapy on the superior and inferior orbicularis oris (OOS and OOI) and mentalis (MT) muscles at rest and with lips closed in mouth breathing patients with no nasal airway obstruction. The sample consisted of 13 children aged 5-10 years. Clinical and electromyographic evaluations were performed before and after treatment. The results showed that muscles (P < 0.05) and functions (P < 0.01) improved after therapy, which can be observed by clinical evaluations. The electrical activity increase between rest and closed lip positions was statistically significant for the muscles studied. Before therapy the significant minimal level (s.m.l.) was P < 0.01 and after therapy it was P < 0.05. When the difference between the rest and closed lip positions before and after therapy was compared, a statistically significant decrease (P < 0.05) in the electrical activity of the OOI and MT muscles was observed. There was no correlation between the root-mean-square (RMS) of the OOI and MT muscles with the morphological and functional evaluations. The therapy can improve morphology and function of the muscles in mouth breathing patients with no nasal airway obstruction.

EMG activity of the orbicularis oris and mentalis muscles in children with malocclusion, incompetent lips and atypical swallowing--part II.

The EMG activity of the orbicularis oris (upper and lower), and of the mentalis muscles was verified during several movements of the lips, in 18 children ageing from 8 to 12 years, divided into three groups: one with normal occlusion, and two with class II division 1, with atypical swallowing and/or incompetent lips and who had received no orthodontic treatment. In blowing through a straw the muscular activity of the orbicularis oris and the mentalis was significantly greater in the incompetent lips group. The mentalis presented moderate activity in the competent lips group and negligible in normal occlusion. In puffing out of the cheeks, the malocclusion groups developed marked activity of the orbicularis oris and very marked activity of the mentalis, while the normal occlusion presented moderate and negligible activities, respectively. In pursing of the lips, only the incompetent lips group presented a very marked activity of the lower segment. The compression of the lips against the teeth revealed a marked activity of the upper segment of the orbicularis oris in the groups of malocclusion and the mentalis presented greater activity in the competent lips group. The reciprocal compression of the lips presented a hyperactivity of the three muscles.

Electromyographic analysis of the superior belly of the omohyoid muscle and anterior belly of the digastric muscle in tongue and head movements.

The participation of the superior belly of the omohyoid muscle and anterior belly of the digastric muscle in tongue and head movements was studied eletromyographically in 20 normal young volunteers. A pair of monopolar electrodes was used in each muscle for simultaneous recording of their actions. The muscles act in the following tongue movements: protrusion, right and left lateral movements, placement of the tip of the tongue on soft and hard palates and on the floor of the mouth. The strongest levels of activity of the superior belly of the omohyoid muscle were observed in the placement of the tip of the tongue on the soft palate, coincidentally with a greater dislocation of hyoid bone. Both of the muscles studied did not participate in the head's kinesiology.

Evaluation of electromyographic activity and heart rate responses to isometric exercise. The role played by muscular mass and type.

The purpose of the present study was to examine the relationship between the electromyographic (EMG) activity and heart rate (HR) responses induced by isometric exercise performed by knee extension (KE) and flexion (KF) in men. Fifteen healthy male subjects, 21 +/- 1.3 years (mean +/- SD), were submitted to KE and KF isometric exercise tests at 100% of maximal voluntary contraction (MVC). The exercises were performed with one leg (right or left) and with two legs simultaneously, for 10 s in the sitting position with the hip and knee flexed at 90 degrees. EMG activity (root mean square values) and HR (beats/min) were recorded simultaneously both at rest and throughout the sustained contraction. The HR responses to isometric exercise in KE and KF were similar when performed with one and two legs. However, the HR increase was always significantly higher in KE than KF (P < 0.05), whereas the EMG activity was higher in KE than in KF (P < 0.05), regardless of the muscle mass (one or two legs) involved in the effort. The correlation coefficients between HR response and the EMG activity during KE (r = 0.33, P > 0.05) and KF (r = 0.15, P > 0.05) contractions were not significant. These results suggest that the predominant mechanism responsible for the larger increase in HR response to KE as compared to KF in our study could be dependent on qualitative and quantitative differences in the fiber type composition found in each muscle group. This mechanism seems to demand a higher activation of motor units with a corresponding increase in central command to the cardiovascular centers that modulate HR control.