Dissertations / Theses on the topic 'Flexor muscles of the forearm'

This study is aimed to determine the electromyographic signals of the forearm, using Ag/AgCl electrodes. The four major muscles of forearm, which are providing the bioelectrical currents, have been displayed and analysed to determine the different activities. In order to record the signals, an EMG device has been developed and installed and a schematic has also been presented in this paper.

Orientador: Fausto Berzin
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba
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Resumo: A eletromiografia de superfície é um instrumento potencial para estudos anatômicos, clínicos e cinesiológicos da atividade elétrica muscular e tem sido aplicada para identificar padrões de ativação muscular associados com força e fadiga muscular. A suplementação de creatina tem sido utilizada para aumentar a força e eficiência muscular, bem como diminuir o início da fadiga muscular. Assim, o objetivo deste trabalho foi analisar a atividade eletromiográfica e força dos músculos bíceps braquial (BB), braquiorradial (BR) e flexor ulnar do carpo (FUC) em indivíduos submetidos à suplementação aguda e crônica de creatina. Vinte indivíduos do sexo masculino, idade 18-35 anos, treinados em exercícios resistidos (musculação), foram selecionados para este estudo duplo-cego, randomizado, placebo-controlado. Os voluntários foram divididos em dois grupos: creatina (5 g de creatina e 5 g de maltodextrina, n=10) e placebo (5 g de celulose e 5 g de maltodextrina, n=10). A suplementação foi ingerida quatro vezes ao dia durante os primeiros 7 dias, e uma vez ao dia durante os 49 dias subsequentes. Cada voluntário realizou contração voluntária isométrica máxima (CVIM) de flexão do antebraço e com 30% e 60% da CVIM, antes e após 7 e 56 dias de suplementação. Os sinais eletromiográficos foram captados utilizando eletrodos de superfície passivos conectados a um pré-amplificador, registrados em um eletromiógrafo computadorizado, e analisados pelo software Myosystem-Br1. Uma célula de carga foi empregada para medir a força isométrica máxima durante os testes. Os dados eletromiográficos foram calculados pelos valores de amplitude (RMS - root mean square) e freqüência mediana (FM), e analisados por meio de curva de regressão linear, gerando coeficientes angulares de RMS e FM que foram considerados índices de eficiência e fadiga muscular, respectivamente. Os resultados mostraram que o grupo creatina exibiu aumento da força somente após 56 dias de suplementação (p < 0,05), enquanto nenhuma diferença foi encontrada no grupo placebo. Os músculos BB e BR mostraram decréscimo nos valores de coeficientes angulares de RMS após 7 e 56 dias de suplementação de creatina com 60% da CVIM (p < 0,05). Nenhuma diferença significante foi observada nos valores de coeficientes angulares de FM entre os tempos de suplementação para todos os músculos, em ambos os grupos e cargas. Assim, pode ser concluído que a suplementação crônica de creatina aumenta a força isométrica de flexão do antebraço. Além disso, tanto a suplementação aguda como a crônica de creatina melhoram a eficiência muscular de BB e BR apenas com cargas maiores, porém não tem efeito benéfico na redução da fadiga muscular de BB, BR e FUC, em qualquer intensidade de carga
Abstract: Surface electromyography is a potential tool for anatomic, clinic and kinesiologic studies of muscle electric activity and it has been employed to identify muscular activation levels associated with force and muscular fatigue. Creatine supplementation has been used to augment the strength and muscular efficiency as well to decrease the onset of muscular fatigue. This study aimed to analyze the force and electromyographic activity of biceps brachii (BB), brachioradialis (BR) and flexor carpi ulnaris (FCU) muscles in subjects submitted to acute and chronic creatine supplementation. Twenty resistance-trained male volunteers, aged 18 to 35 years, were selected for this double-blind, controlled-placebo, randomized study. Volunteers were placed into two groups: creatine (5 g creatine and 5 g maltodextrine, n=10) and placebo (5 g cellulose and 5g maltodextrine, n=10). Oral supplementation was given 4 times per day during the first 7days and once a day in the 49 subsequent days. Volunteers performed maximum isometric voluntary contraction (MIVC) of forearm flexion and with 30% and 60% MIVC, before and after 7 and 56 days of supplementation. Electromyographic signs were captured using passive surface electrodes joined to a pre-amplifier, recorded in a computer-connected electromyography and analyzed by the Myosystem-Br1 software. A load cell was used to measure the maximum isometric strength during the tests. Electromyographic data were calculated by values of amplitude (RMS - root mean square) and median frequency (MF) and analyzed by linear regression curve, generating RMS and MF slopes that were considered muscular efficiency and fatigue indices, respectively. Results showed that creatine group exhibited an increase of strength only after 56 days of supplementation (p < 0.05), while no significant difference was found in placebo group. BB and BR muscles showed a decrease of RMS slopes after 7 and 56 days of creatine supplementation with 60% MIVC (p < 0.05). No significant difference was observed in MF slopes among times of supplementation for all muscles in both loads and groups. It can be concluded that the chronic creatine supplementation increases the isometric strength of forearm flexion. Also, both acute and chronic creatine supplementation improve the BB and BR muscular efficiency only with high loads, but do not have beneficial effect on reducing muscular fatigue of BB, BR and FCU, whichever the load
Doutorado
Anatomia
Doutor em Biologia Buco-Dental

Aim The present thesis aimsto provide scientific based evidence that might expand the limited information available regarding the post-activation potentiation (PAP) effects on the rate of torque development (RTD) and muscle activity during repeated isokinetic concentric maximal voluntary contractions(MVC). Additionally, we aim to provide new insights related to the possible effects that such repeated maximal contractions might have on the muscle tendon unit (MTU) stiffness. Methods Nine active participants were tested in two separate sessions. Participants performed plantar flexor supra-maximal twitches evoked via electrical stimulation of the tibial nerve and concentric MVC sat 60°/s. These were evoked/performed before and from 5s to 15 minutes after a 6s plantar flexion maximal voluntary isometric contraction (MVIC). Twitch RTD and time to peak torque (TTP) were measured. Concentric MVC peak torque (PT), soleus, medial and lateral gastrocnemius muscle activation, as well as RTD during different portions of the rising torque curve (e.g.50-100ms) were assessed. Passive stiffness index of the MTU was calculated using the torque-angle relation attained during the 5°/spassive ankle angle rotation that followed each maximal concentric contraction. Results TwitchRTD significantly increased immediately after the conditioning contraction (CC)and remained enhanced for 5s-8min, with increases of 59.7%-6.0%. Twitch TTP significantly decreased from 5s-1min postCC by 9.9%-2.0%. TTP then increased by 4.6%-2.2% from 3-8min. In the maximal voluntary concentric contractions, there was a significant increase of 5.7, 6.0 and 5.9% at 1.5, 3, and 5min respectively in the PT. Voluntary RTD showed significant increases during the 100-200ms, 50-200ms and 0-200ms phases. These increases were seen at 3min (7.3%), 1.5-5min (8.0-6.9%), and 1.5-5min (8.6-9.5%) respectively. Stiffness showed no significant changes and any changes in EMG do not appear to be due to PAP effects. Conclusions The results from the current study show that PAP affects voluntary performance at a lower angular velocitythan previously reported and in a time frame where twitch contractile properties were also potentiated. The lack of stiffness changes suggests that the acute effects might be mainly related to mechanisms within the muscle and that similar testing protocols should expect low interference from factors related to passive MTU stiffness changes.

Kursen Projektarbete.

Los movimientos voluntarios del cuerpo son controlados por el sistema nervioso central y periférico a través de la contracción de los músculos esqueléticos. La contracción se inicia al liberarse un neurotransmisor sobre la unión neuromuscular, iniciando la propagación de un biopotencial sobre la membrana de las fibras musculares que se desplaza hacia los tendones: el Potencial de Acción de la Unidad Motora (MUAP). La señal electromiográfica de superficie registra la activación continua de dichos potenciales sobre la superficie de la piel y constituye una valiosa herramienta para la investigación, diagnóstico y seguimiento clínico de trastornos musculares, así como para la identificación de la intención movimiento tanto en términos de dirección como de potencia. En el estudio de las enfermedades del sistema neuromuscular es necesario analizar el nivel de actividad, la capacidad de producción de fuerza, la activación muscular conjunta y la predisposición a la fatiga muscular, todos ellos asociados con factores fisiológicos que determinan la resultante contracción mioeléctrica. Además, el uso de matrices de electrodos facilita la investigación de las propiedades periféricas de las unidades motoras activas, las características anatómicas del músculo y los cambios espaciales en su activación, ocasionados por el tipo de tarea motora o la potencia de la misma. El objetivo principal de esta tesis es el diseño e implementación de protocolos experimentales y algoritmos de procesado para extraer información fiable de señales sEMG multicanal en 1 y 2 dimensiones del espacio. Dicha información ha sido interpretada y relacionada con dos patologías específicas de la extremidad superior: Epicondilitis Lateral y Lesión de Esfuerzo Repetitivo. También fue utilizada para identificar la dirección de movimiento y la fuerza asociada a la contracción muscular, cuyos patrones podrían ser de utilidad en aplicaciones donde la señal electromiográfica se utilice para controlar interfaces hombre-máquina como es el caso de terapia física basada en robots, entornos virtuales de rehabilitación o realimentación de la actividad muscular. En resumen, las aportaciones más relevantes de esta tesis son: * La definición de protocolos experimentales orientados al registro de señales sEMG en una región óptima del músculo. * Definición de índices asociados a la co-activación de diferentes músculos * Identificación de señales artefactuadas en registros multicanal * Selección de los canales mas relevantes para el análisis  Extracción de un conjunto de características que permita una alta exactitud en la identificación de tareas motoras Los protocolos experimentales y los índices propuestos permitieron establecer que diversos desequilibrios entre músculos extrínsecos del antebrazo podrían desempeñar un papel clave en la fisiopatología de la epicondilitis lateral. Los resultados fueron consistentes en diferentes ejercicios y pueden definir un marco de evaluación para el seguimiento y evaluación de pacientes en programas de rehabilitación motora. Por otra parte, se encontró que las características asociadas con la distribución espacial de los MUAPs mejoran la exactitud en la identificación de la intención de movimiento. Lo que es más, las características extraídas de registros sEMG de alta densidad son más robustas que las extraídas de señales bipolares simples, no sólo por la redundancia de contacto implicada en HD-EMG, sino también porque permite monitorizar las regiones del músculo donde la amplitud de la señal es máxima y que varían con el tipo de ejercicio, permitiendo así una mejor estimación de la activación muscular mediante el análisis de los canales mas relevantes.
Voluntary movements are achieved by the contraction of skeletal muscles controlled by the Central and Peripheral Nervous system. The contraction is initiated by the release of a neurotransmitter that promotes a reaction in the walls of the muscular fiber, producing a biopotential known as Motor Unit Action Potential (MUAP) that travels from the neuromuscular junction to the tendons. The surface electromyographic signal records the continuous activation of such potentials over the surface of the skin and constitutes a valuable tool for the diagnosis, monitoring and clinical research of muscular disorders as well as to infer motion intention not only regarding the direction of the movement but also its power. In the study of diseases of the neuromuscular system it is necessary to analyze the level of activity, the capacity of production of strength, the load-sharing between muscles and the probably predisposition to muscular fatigue, all of them associated with physiological factors determining the resultant muscular contraction. Moreover, the use of electrode arrays facilitate the investigation of the peripheral properties of the active Motor Units, the anatomical characteristics of the muscle and the spatial changes induced in their activation of as product of type of movement or power of the contraction.The main objective of this thesis was the design and implementation of experimental protocols, and algorithms to extract information from multichannel sEMG signals in 1 and 2 dimensions of the space. Such information was interpreted and related to pathological events associated to two upper-limb conditions: Lateral Epicondylitis and Repetitive Strain Injury. It was also used to identify the direction of movement and contraction strength which could be useful in applications concerning the use of biofeedback from EMG like in robotic- aided therapies and computer-based rehabilitation training.In summary, the most relevant contributions are:§The definition of experimental protocols intended to find optimal regions for the recording of sEMG signals. §The definition of indices associated to the co- activation of different muscles. §The detection of low-quality signals in multichannel sEMG recordings.§ The selection of the most relevant EMG channels for the analysis§The extraction of a set of features that led to high classification accuracy in the identification of tasks.The experimental protocols and the proposed indices allowed establishing that imbalances between extrinsic muscles of the forearm could play a key role in the pathophysiology of lateral epicondylalgia. Results were consistent in different types of motor task and may define an assessment framework for the monitoring and evaluation of patients during rehabilitation programs.On the other hand, it was found that features associated with the spatial distribution of the MUAPs improve the accuracy of the identification of motion intention. What is more, features extracted from high density EMG recordings are more robust not only because it implies contact redundancy but also because it allows the tracking of (task changing) skin surface areas where EMG amplitude is maximal and a better estimation of muscle activity by the proper selection of the most significant channels.

This thesis presents contributions to the kinematic and muscular characterisation of the hand during the activities of daily living (ADL). Orientation and position data of the rotation axes of metacarpophalangeal and interphalangeal joints are provided, obtained in vivo using a robust optimization method. Multivariate statistical methods are used for dimensional reduction of kinematics by identifying synergies (and providing their temporal evolution during ADL and grasps), and to identify a minimum set of representative forearm areas of superficial muscle activity (sEMG) during ADL. The role of the muscles to perform different grasps is deepened, and a synchronized database of sEMG and hand kinematics in ADL is presented. Finally, the database is used in a preliminary study of the relationship between kinematics and sEMG during reaching and manipulation phases. The results can be applied in prosthetic control and functional evaluation.
Esta tesis presenta contribuciones a la caracterización cinemática y muscular de la mano durante la realización de actividades de la vida diaria (AVD). Se proporcionan datos de orientación y posición de los ejes de rotación de articulaciones metacarpofalángicas e interfalángicas, obtenidos in vivo aplicando un método de optimización robusto. Se utilizan métodos de estadística multivariante para la reducción dimensional de la cinemática identificando sinergias (y proporcionando su evolución temporal durante AVD y agarres), y para identificar un conjunto mínimo de zonas representativas de la actividad muscular superficial (sEMG) durante AVD. Se profundiza en el rol de los músculos para realizar diferentes agarres, y se presenta una base de datos sincronizada de sEMG y cinemática en AVD, sobre la que se acomete un estudio preliminar de la relación entre cinemática y sEMG en las fases de alcance y manipulación, con resultados de aplicación en el control de prótesis y evaluación funcional.

Purpose: 1, to determine effect of education and exercise on neck pain, disability, cervical posture and muscle function in office workers with sub-clinical neck symptoms; 2, to determine differences in forward head posture in preferred and standardized posture, and 3, to explore the influence of time on work posture in a sub-group of office workers. Subjects: Sixty-six office workers with sub-clinical neck symptoms who utilize computers at least 4 hours per day participated. A sub-group of 27 were videotaped to assess posture over a workday. Methods: Videotaping was performed 15 minutes of the first and last hour of the workday for analysis of the craniovertebral angle. Cervical posture using the CROM was measured on all subjects in standardized and preferred positioning of the trunk and lower extremities. Subjects were randomly assigned to one of three groups: education only (EOG), education and exercise (EEG), or control (CG). Pre and post-test measurements of pain (Visual Analog Scale), disability (NeckDisability Index), forward head posture (FHP), and deep cervical flexor muscle function (Craniocervical Flexion Test and Short Neck Flexor Endurance Test) were assessed for change within group as well as differences between groups over the 8 week period. Results: No difference was found for FHP over 8 hours in the subgroup. FHP was greater in preferred position compared to standardized by 7.59 mm (95% CI 6.27-8.92, p<.001). Median and mean scores improved for all 3 groups on pain and disability with greater improvement in intervention groups. FHP was unchanged/slightly worse in the CG and EOG, and improved in the EEG. Muscle function improved for the EEG. Statistical significance was not found for change scores between groups. Posttest scores were statistically significant for the NDI between EEG (20.45) and the CG (34.47), p=.042, and between the EEG and the EOG (34.59), p=.023 using Kruskall Wallis with adjusted significance for pairwise comparisons. Discussion/Conclusions: Posture over the workday did not change, differences were found based on preferred and standardized positions. Exercise and education intervention for those with sub-clinical neck symptoms show promise but did not demonstrate significance improvement over controls in this study.

O controle postural em idosos tem sido estudado com o objetivo de melhor entender os fatores que levam esta população a sofrer mais quedas que os indivíduos jovens. A maior variabilidade de força dos músculos flexores plantares (MFP) aparenta estar diretamente associada ao menor controle postural principalmente em adultos jovens. Além disto, o treinamento específico de estabilidade de força dos MFP em baixas intensidades parece diminuir a variabilidade de força destes músculos e também diminuir a oscilação postural de adultos jovens. Entretanto, faltam esclarecimentos sobre a associação entre variabilidade de força dos MFP e oscilação postural na população idosa, bem como os efeitos de um treinamento específico de estabilidade de força destes músculos para esta mesma população. Sendo assim, o objetivo do presente estudo foi analisar a associação entre variabilidade de força dos MFP e a oscilação postural de idosas e examinar os efeitos do treinamento de estabilidade de força na variabilidade da força dos MFP, na coativação muscular dos músculos tibial anterior (TA) e gastrocnêmio medial (GM) e na oscilação corporal destas idosas. Para isto, 40 mulheres idosas foram divididas em quatro grupos: Grupo GT5 (n=10) que realizou treinamentos a 5% da contração isométrica voluntária máxima (CIVM) dos MFP; Grupo GT10 (n=10) que realizou treinamentos a 10% da CIVM dos MFP; Grupo GTLP (n=10) que realizou treinamentos a 10% de uma repetição máxima dos MFP no equipamento Leg Press; Grupo GC (n=10) que não realizou nenhum treinamento específico para os MFP e foi utilizado como controle. Foram avaliadas a oscilação corporal durante a manutenção da postura bipodal ereta, a variabilidade da força dos MFP e a coativação muscular dos músculos TA e GM antes e após o período de treinamento. Este treinamento foi realizado uma vez por semana durante quatro semanas. Em cada sessão de treino a participante realizou cinco séries em que mantinha por 30 segundos a força isométrica de flexão plantar, de acordo com as especificações de seu grupo. Os resultados revelaram que o treinamento de estabilidade de força dos MFP realizado pelos grupos GT5, GT10 e GTLP foi eficiente e diminuiu a variabilidade de força das participantes na condição de 5% da CIVM com feedback visual, além disso, mostrou que o grupo GT5 também diminuiu sua variabilidade de força para a condição 10% da CIVM com feedback visual. Em relação ao controle postural, foi observado que os grupos GT5 e GT10 aumentaram sua amplitude média de oscilação na direção ântero-posterior após o treinamento. Com relação à ativação dos músculos TA e GM, os grupos GT5 e GT10 diminuíram o índice de coativação muscular para as condições 5% e 10% com feedback visual após o treinamento e o grupo GT5 ainda apresentou diminuição da coativação para a condição 5% sem feedback visual. Finalmente, os resultados apontaram que para população idosa não há relação entre a variabilidade de força dos MFP e o controle da postura. Portanto, estes resultados indicam que, na população idosa não existe associação entre controle postural e variabilidade de força dos MFP, e mesmo que não esteja claro o efeito do treinamento no controle da postura, a redução da variabilidade da força e coativação muscular podem ser interpretadas como um ganho em termos de controle motor
Elderly postural control has been studied in order to better understand the factors that lead this population to suffer more falls than young individuals. Greater variability of plantar flexor muscles (PFM) strength appears to be directly associated to lower postural control mainly in young adults. In addition, specific training of PFM strength stability at low intensities seems to decrease force variability of these muscles and also to decrease postural oscillation of young adults. However, there is a lack of clarification about the association between PFM force variability and postural oscillation in elderly population, as well as the effects of specific stability strength training of these muscles for this same population. Thus, the objective of the present study was to analyze the association between PFM force variability and postural oscillation in elderly, and to examine the effects of strength stability training on PFM force variability in the muscle coactivation of anterior tibial muscles (AT) and medial gastrocnemius (MG) and in the body oscillation of these elderly women. For this, 40 elderly women were divided into four groups: Group TG5 (n = 10) who performed training at 5% of maximal voluntary isometric contraction (MVIC) of PFM; TG10 group (n = 10) who performed training at 10% of the MVIC of PFM; TGLP group (n = 10) who underwent training at 10% of a maximum repetition of the PFMs in the Leg Press equipment; Group CG (n = 10) who did not perform any specific training for PFMs and was used as control. Body oscillation was evaluated during maintenance of upright bipodal posture, PFM force variability, and muscle coactivation of AT and MG muscles before and after the training period. This training was performed once a week for four weeks. In each training session participant performed five series in which he maintained for 30 seconds the isometric force of plantar flexion, according to the specifications of his group. The results showed that the PFM force stability training performed by TG5, TG10 and TGLP groups was efficient and decreased the strength variability of the participants in the 5% condition of the MVIC with visual feedback, in addition, showed that the TG5 group also decreased its force variability to the 10% MVIC condition with visual feedback. Regarding the postural control, it was observed that the TG5 and TG10 groups increased their mean amplitude of oscillation in the anteroposterior direction after the training. Regarding the activation of the AT and MG muscles, the TG5 and TG10 groups decreased the muscle activation rate for the 5% and 10% conditions with visual feedback after the training and the TG5 group still showed a decrease of the coactivation for the condition 5% without visual feedback. Finally, the results pointed out that for the elderly population there is no relation between the PFM strength variability and the posture control. Therefore, these results indicate that, in the elderly population, there is no association between postural control and PFM strength variability, and even though the effect of training on posture control is not clear, the reduction in strength variability and muscle coactivation can be interpreted as a gain in terms of motor control

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Universidade Federal de Minas Gerais
The relation between flexibility alterations and muscular torque posstretching is not so exploited in literature. There are many stretching techniques and posture used in clinics and sportive activities. The technique of eccentric active stretching in a standing posture, with weight unloading in the stretched limb, is one of them. Thus, a better knowledge of the alterations caused after its application will provide scientific support for its usage. Objective: To evaluate the effects of an eccentric active stretching program of the knee flexor muscles in the standing posture on the evaluated limb on: knee extension ROM, passive torque of knee flexor muscles and isometric and isokinetic concentric and eccentric torque of flexor and extensor muscles of the knee. Methodology: 34 healthy and sedentary volunteers, both genders (34,42 ± 9,3 years) were evaluated. All of them had 20° or more knee flexor muscles shortening. The stretching program was performed twice a week, for four weeks and consisted of 7 consecutive repetitions of 1 min each one with a 30s rest between them. Knee ROM and knee torque were evaluated using an Isokinetic Dynamometer before and after four weeks of intervention. The passive torque and knee ROM were measured passively, while the isometric, concentric and eccentric torque of the flexor and extensor of the knee were measured through maximal voluntary contractions (speeds 30°/s, 60°/s). Results: There was an increase in the knee extensor ROM from 53,7 ± 13° to 30,1 ± 16° (p = 0,0001). No alteration occurred in the passive torque (from 11,2 ± 3N to 10,6 ± 3N; p = 0,09). The isometric extensor and flexor torque increased from 68 ± 67,8N to 187,58 ± 73,5N (p = 0,006) and from 89,68 ± 32,62N to 93,87 ± 33,12N (p = 0,01), respectively. There was a gain of knee extensor concentric torque at 60°/s from 144,44 ± 51,6N to 151,57 ± 58,2N (p = 0,02) and knee extensor eccentric torque at 30°/s from 175,4 ± 71,6N to 189,9 ± 73,8N (p = 0,01). There was an improvement in the flexor eccentric and concentric torque at 30º /s (from 100,3 ± 34,2N to 105,63 ± 35N; p = 0,02 and from 90,7 ± 31,7N to 96,7 ± 31,8N; p = 0,001, respectively). Conclusions: The eccentric active stretching program of the knee flexor muscles in a standing posture was effective to increase knee extension ROM, improving flexibility in the knee flexor muscles, although there was no change in the passive torque. It also improved the isometric and isokinetic peak torque from the muscle group submitted to the stretching and its antagonist group.
A relação entre alterações na flexibilidade e torque muscular pósalongamentos tem sido pouco explorada pela literatura. São inúmeras as técnicas e posturas de alongamento sendo utilizadas tanto nas clínicas quanto em atividades esportivas. A técnica de alongamento ativo excêntrico realizada na postura em pé, com descarga de peso no membro alongado, estão entre elas. Sendo assim, o maior conhecimento das alterações geradas após sua aplicação, dará suporte para que sejam executadas mediante evidências científicas que comprovem sua eficácia. Objetivo: foi avaliar o efeito de um programa de alongamento ativo excêntrico dos músculos flexores do joelho na postura em pé com descarga de peso no membro avaliado, sobre as variáveis: Amplitude de movimento (AM) de extensão do joelho, torque passivo dos músculos flexores do joelho e torque isométrico e isocinético dos músculos extensores e flexores do joelho. Metodologia: foram selecionados 34 voluntários, de ambos os sexos, com idade de 34,42 ± 9,3 anos, sedentários, saudáveis e com, no mínimo, 20º de encurtamento dos músculos flexores do joelho. Todas as variáveis estudadas foram avaliadas pré e pós-programa de alongamento, em um Dinamômetro Isocinético (Biodex Multi-joint System 3). O programa de alongamento dos músculos flexores do joelho foi realizado duas vezes por semana durante quatro semanas. Cada sessão de alongamento consistiu de sete repetições de 1min de alongamento intercaladas com 30 s de repouso. A avaliação da Amplitude de movimento e do torque passivo foram realizados passivamente. O toque isométrico e isocinético concêntrico e excêntrico dos músculos extensores e flexores do joelho, foram testados por meio de contrações voluntárias máximas Contração Voluntária Máxima (CVM) nas velocidades a 30º/s e 60º/s. Resultados: demonstraram aumento na amplitude de movimento de extensão do joelho de 53,7 ± 13° para 30,1 ± 16° (p = 0,0001). O valor do torque passivo não alterou significativamente (11,2 ± 3N para 10,6 ± 3N; p = 0,09). O torque isométrico extensor aumentou de 178,68 ± 67,8N para 187,58 ± 73,5N (p = 0,006) e o flexor de 89,68 ± 32,62N para 93,87 ± 33,12N (p = 0,01). O torque isocinético concêntrico dos músculos extensores aumentou a 60°/s de 144,44 ± 51,6 N para 151,57 ± 58,2N; (p = 0,02) e o excêntrico a 30°/s de 175,4 ± 71,6 N para 189,9 ± 73,8 N; (p = 0,01). O torque isocinético tanto excêntrico quanto concêntrico dos músculos flexores do joelho aumentou a 30°/s (de 100,3 ± 34,2 N para 105,63 ± 35 N; p = 0,01 e de 90,7 ± 31,7 N para 96,7 ± 31,8 N; p = 0,001, respectivamente). Conclusão: o programa de alongamento ativo excêntrico dos músculos flexores do joelho, realizado na postura em pé, foi efetivo em aumentar a amplitude de movimento de extensão do joelho, sendo assim aumentou a flexibilidade dos flexores do joelho, embora não tenha constatado alteração no torque passivo. Também se mostrou eficaz em aumentar o pico de torque isométrico e isocinético tanto do grupo muscular submetido ao alongamento quanto do seu antagonista.

Title: Effect of strength training with vascular occlusion on the forearm flexor muscle strength. Aims: The aim is to determine the effect of vascular occlusion on maximum isometric strength of forearm muscles. Methodology: The research group of 8 volunteers underwent six weeks of exercise program for upper limb (UL). The exercise program was different for each upper limb. Probands practiced one UL with vascular occlusion and second one without vascular occlusion. The research group was measured maximal isometric strength of forearm muscles before the 6-week exercise block, after 3 weeks of training and after completion of the cycle. All measurements were carried out in the laboratory climbing walls FTVS UK. The results were statistically evaluated using test ANOVA with repeated measurement. Results: The results of examining the impact of vascular occlusion to increase muscle strength flexor forearm in this thesis confirmed. Testing did not find significant differences in absolute strength or relative strength between exercise with vascular occlusion and exercise without vascular occlusion. Absolute strength at exercise with vascular occlusion averaged before exercise program 422 N, after the completion of 461 N. Absolute strength at exercise without vascular occlusion averaged before exercise...

The intensity of corticosteroid-induced blanching has been found to vary at different areas of the flexor aspect of the human forearm. A retrospective analysis of 38,880 observations of skin blanching in 56 volunteers was conducted to assess the sensitivity of forearm skin to betamethasone 17-valerate. The mid-forearm appears to be more sensitive to the blanching response than do the areas close to the wrist or elbow. These results indicate that each preparation under evaluation should be applied to several sites along the forearm when using the human skin blanching assay in order to obtain an accurate comparative assessment of corticosteroid release from topical delivery vehicles.

Title: Discrimination of EMG signals from individual forearm muscles from surface EMG Abstract: Location of electrodes for sensing the forearm muscles using surface electromyography is not accurately described. It is based only on recommendations by various authors in making researches. The aim of this study was to determine the optimal placement of electrodes on the forearm and describe it to another repeatable measurements. By analyzing the amplitude of EMG recording is confirmed not only the optimal location of electrodes, but either suggested muscle synergies that are possible to analyze more deeply in other studies because a detailed examination of muscle synergies are considerable application in upper limb prosthetics Keywords: Surface electromyography, forearm muscles, amplitude analysis

Thesis (M.Tech.: Chiropractic)- Dept. of Chiropractic, Durban Institute of Technology, 2002. 113 leaves
Lateral epicondylitis is the most common cause of chronic lateral elbow pain in adults (Bowen et al. 2001:642). No uniform treatment regime is available for lateral epicondylitis, although most authors do agree that treatment should begin with a conservative approach before progressing to more complex and invasive therapies (Kamien 1990:174). The purpose of this study was to investigate the relative effectiveness of dry needling myofascial trigger points of the forearm extensor muscles as an adjunct to cross friction massage, in the treatment of lateral epicondylitis.