The purposes of this dissertation were to determine: 1) the relationship betweenmuscle thickness change (MTC) as measured by rehabilitative ultrasound imaging(RUSI) and EMG activity in the lumbar multifidus (LM), 2) if motor control changesproduced by experimentally induced pain are measurable with RUSI, 3) if a differenceexists in MTC between subjects with low back pain (LBP) classified in the treatmentbasedclassification system (TBC) system and controls, 4) if MTC improves followingintervention.Current literature suggests sub-groups of patients with LBP exist and responddifferently to treatment, challenging whether the majority of LBP is "nonspecific". TheTBC system categorizes subjects into one of four categories (stabilization, mobilization,direction specific exercise, or traction). Currently, only stabilization subjects receive anintervention emphasizing stability. Because recent research has demonstrated that motorcontrol impairments of lumbar stabilizing muscles are present in most subjects with LBP,it is hypothesized that impairments may be present across the TBC classifications.Study 1: Established the relationship between MTC as measured by RUSI andEMG in the LM. Study 2: Assessed MTC of the LM during control and painfulconditions to determine if induced pain changes in LM and transverse abdominis (TrA)are measurable with RUSI. Study 3: Measured MTC of the LM and TrA in subjects withLBP classified in the TBC system and 20 controls. Subjects completed a stabilizationprogram and were re-tested.The inter-tester reliability of the RUSI measurements was excellent (ICC3,3 =.91,SEM=3.2%). There was a curvilinear relationship (r = .79) between thickness changeand EMG activity. There was a significant difference (p andlt; .01) between control andpainful conditions on 4 of the 5 LM tasks tested and on the TrA task. There was adifference in MTC between subjects and controls on the loaded LM test which varied bylevel and category. All categories were different from control on the TrA. Followingintervention the TrA MTC improved (p andlt; .01). The LM MTC did not (p values from .13-.86).These findings suggest MTC can be clinically measured and that deficits existwithin TBC system. Significant disability and pain reduction were measured.

Similar to quadrupedal animals, there is evidence in humans of interlimb signalling during upper and lower limb muscular activation. A product of these interconnections is modulation of motor output via remote neural input. Such remote communication can take several forms; for example, movement modifies activity between upper and lower limbs (e.g. arms to legs) and between a limb pair (e.g. one leg to the other). A specific form of modulation between homologous muscles bilaterally (i.e. the corresponding motor unit pool across the spinal cord) is also seen with strength training. However, details of these motor connections are not well known. Improved understanding of remote influences on motor output and coordination patterns may be valuable in an applied motor re-training setting. Abnormal excitability within reflex pathways of lower limb musculature is common among various neurological disorders. Thus, it is of interest whether remote inputs could be exploited to help normalize dysfunctional motor output. The primary goal of this thesis was to better our understanding of neural interlimb connections; specifically, to examine modulatory responses within the ankle flexor and extensor muscles induced by remote muscular activation associated with both rhythmic arm movement and contralateral resistance training. Further, the final objective of this work was to apply these earlier observations in the context of a post-stroke rehabilitation paradigm, aimed at normalizing muscle activation patterns within the more-affected limb. Initially, this thesis examined spinal reflex excitability within functional antagonists of the lower leg, the ankle flexors and extensor muscles, and the impact of transient, rhythmic movement on these neural networks. Hoffmann (H-) reflexes were first used as a measurement probe. Rhythmic arm cycling significantly suppressed reflex amplitude in extensors, but revealed a bidirectional (i.e. either suppression or facilitation) reflex modulation in flexor muscles. Thus, differential regulation of ankle flexor and extensor H-reflex amplitudes was evidenced during rhythmic arm movement. This may stem from differences in locomotor pattern generator output to these groups as well as increased involvement of cortical drive to the flexors relative to the extensors during rhythmic movement. These results support the presence of interlimb neural coupling, such that remote motor action (arm movement) influences lumbar spinal cord excitability. Additionally, these descending signals impact ankle flexors and extensors differentially, which illustrates a method of producing facilitative modulation of ankle flexor motor responses. Second, reciprocal inhibition (RI) was used to examine regulation of excitability between these same lower limb functional antagonists during rhythmic arm movement. Arm cycling significantly increased RI in ankle extensors, but had no effect in the flexors. This extends observation of remote motor activity-induced modulation on spinal excitability to the core circuitry that comprises the interaction between functional agonist/antagonist pairs. Moreover, the asymmetry of this effect highlights differences in descending supraspinal inputs to ankle flexors vs. extensors, and may be related to functional dorsiflexion requirements during locomotion. Subsequently, this thesis explored long term plasticity of interlimb neural modulation resulting from remote motor activation in the form of resistance training. Specifically, the within limb pair ‘cross-education’ phenomenon was investigated via unilateral isometric strength training of the ankle flexors. The first of these training interventions was implemented in a cohort of neurologically intact subjects who performed five weeks of one-sided maximal isometric dorsiflexion training. H-reflex recruitment curves were used to probe for training-induced spinal plasticity within the agonist (flexor) and antagonist (extensor) muscles bilaterally. Post-intervention, dorsiflexor torque significantly increased in the trained and untrained limbs. Further, significant changes in H-reflex excitability were detected in the trained flexor (agonist) muscle and in both extensor (antagonist) muscles. These findings reveal that muscular crossed effects can be obtained in the ankle dorsiflexor muscles, and provide novel information on agonist and antagonist spinal adaptations that accompany unilateral training. They also suggest potential for application of remote motor activation (resistance training) to induce interlimb neural plasticity within a clinical context, such as improving one-sided weakness and/or motor dysfunction following neurotrauma. The final training intervention was implemented in a chronic (>6mo post-infarct) stroke clinical group who completed six weeks of maximal isometric dorsiflexion training in the less-affected leg. Voluntary isometric strength (dorsiflexion torque, muscle activation), reciprocal inhibition (RI), walking ability and clinical function were used to quantify training effects. Post-intervention, dorsiflexion torque and maximal flexor muscle activation significantly increased in both the more-affected (untrained) and less-affected (trained) legs. Further, the relation between size of RI and level of muscle activation in the more-affected flexor muscle was significantly altered by training, and the Timed Up and Go clinical test was significantly improved. Thus, significant gains in voluntary strength, muscle activation and spinal excitability on the untrained, more-affected side after stroke can be invoked through training the opposite limb. This translates into small but observable functional improvements. Taken together, the data in this thesis provide a basis for novel motor re-training approaches. Improved understanding has been gained of the similarities and differences between remote motor influences received by ankle flexor and extensor muscles in the lower leg. These observations culminate in the implementation of a novel post-stroke training paradigm, which shows that remote muscle activation, i.e. the cross-education effect, can induce strength and functional gains in the more-affected limb. / Graduate

In the healthy young, stimulation of superficial peroneal nerve (SPn) cutaneous afferents at the ankle during walking has been shown to elicit functionally relevant neural and mechanical responses that contribute to obstacle avoidance during swing and have been referred to as stumble corrective responses. However, specific age-related differences in the stumble corrective response induced by electrically evoked cutaneous stimulation have yet to be determined. As a confounding contributor to age related changes in dynamic stability during locomotion, neural and mechanical changes in the stumble corrective response may result in a decreased ability to recover from a destabilizing incident and provide key markers of neuromuscular decline. Therefore the purpose of this study was to compare age-dependent differences in responses to electrically evoked stimulation of the superficial peroneal nerve at the ankle during walking in healthy young and elderly groups. Electromyograms (EMG) of the tibialis anterior (TA), soleus (Sol), medial gastrocnemius (MG), biceps femoris (BF) and vastus lateralis (VL) were recorded along with gait kinematics including joint displacement and angular velocity at the ankle and knee as well as toe clearance relative to the walking surface. Overall, the stumble corrective response was preserved in the elderly as evident by significant responses in kinematics and muscle activity that were similar in sign and phase to those seen in the healthy young. However, the magnitude of the kinematic responses and resulting toe clearance in older adults were significantly smaller than in the young. Further, during the swing phase of unstimulated walking cycles, there were reduced knee flexion, plantarflexion and toe clearance in the elderly with corresponding differences in muscle activity. Therefore, smaller kinematic responses to stimulation, in the elderly, superimposed on a different undisturbed gait profile, resulting in reduced toe clearance, reflects early degradation of the stumble corrective response. This early degradation is likely a prodromal sign of increased fall risk. This supports the potential use of cutaneous reflexes in quantifying degradation of neuromuscular control and its contribution to fall risk. / Graduate / 0317 / 0758 / rbrodie@uvic.ca

This thesis provides new insights about how the brain controls skilled movements, through the study of limb apraxia in two major neurological disorders: Stroke and Corticobasal Syndrome (CBS). Limb apraxia is a cognitive-motor deficit characterized by impairment in the performance of skilled movement. The Conceptual-Production systems model, used as framework in this thesis, proposes that skilled movement is under the control of three systems: a sensory/perceptual system, a conceptual system and a production system. Deficits in any of these systems produce limb apraxia, and depending on which system is affected, a distinct pattern of apraxia emerges. This information processing approach was used to evaluate performance levels, study brain asymmetries and discern patterns of deficits in each population. In addition, longitudinal assessments in sample subsets revealed patterns of recovery after stroke and of progression in CBS. The first study examined acute-subacute and chronic stroke patients with left (LHD) and right hemisphere damage (RHD) for their ability to pantomime and imitate transitive and intransitive gestures. The results indicated that LHD and acute-subacute were more severely impaired. Concurrent deficits in pantomime and imitation were most common, especially after LHD. Since acute-subacute patients were more severely impaired, in the absence of any therapies, it is likely that some degree of recovery occurs over time. The second study study examined longitudinal recovery in a series of transitive gestures tasks among stroke patients and indicated that patients significantly recovered in all tasks, except in Action Identification, a conceptual apraxia task which probes knowledge of actions. Finally, two comparative studies were conducted in CBS, a neurodegenerative disorder in which apraxia is common, making this one of the first studies that evaluated patient performance on a complete limb apraxia battery. The first study found that patients were often impaired on all gesture production tasks, while conceptual knowledge of gestures and tools was usually preserved. A case series constituted the second study, which documented the progression of apraxia in CBS demonstrating that, while deficits in gesture production usually are present at first examination, deficits in conceptual knowledge are infrequent and in many cases do not develop at all. Study limitations were discussed and it was suggested that future research should expand on our findings for recovery in stroke and progression in CBS.

A variabilidade da força muscular, geralmente em uma tarefa de força constante e isométrica, tem sido estudada tanto de forma experimental quanto com o uso de ferramentas computacionais. No entanto, a maioria dos estudos utilizando simulações computacionais tem sido feita em tarefas que utilizam apenas um músculo, geralmente da mão. Até onde se tem conhecimento, não foi feito um estudo, nem experimental nem teórico, abrangendo o comportamento da variabilidade do torque durante a flexão plantar de uma forma geral. Considerando isso, esse trabalho tem como objetivo estudar a variabilidade do torque de flexão plantar por meio de simulações e de modelos matemáticos, comparando os resultados com os obtidos em experimentos realizados localmente. Uma primeira tentativa foi feita utilizando um modelo de contração muscular do tipo Hill ativado pela envoltória dos sinais de eletromiograma captados de cada um dos três músculos do tríceps sural. Essa abordagem não foi bem sucedida em termos da reprodução dos resultados experimentais obtidos de variabilidade do torque em humanos, embora tenha reproduzido bem o valor médio do torque da flexão plantar. Essa impossibilidade em reproduzir os dados experimentais de variabilidade do torque com um modelo ativado por envoltória do eletromiograma provavelmente deveu-se à perda de informação no eletromiograma sobre os disparos dos motoneurônios. Em uma segunda tentativa, os disparos individuais dos motoneurônios foram obtidos de um simulador desenvolvido localmente, chamado de ReMoto, capaz de fornecer os instantes de disparos de todos os modelos de motoneurônios que ativam cada músculo, além de ser capaz de fornecer a força produzida por esse músculo, calculada a partir da força produzida pelas unidades motoras individualmente. No entanto, a versão original do ReMoto foi parametrizada quase que totalmente utilizando dados de gatos e, por isso, foi necessário modificar diversos parâmetros (como amplitude dos abalos e amplitude do potencial de ação da unidade motora) e modelos (como limiar de recrutamento e saturação da força) antes de utilizar o simulador para o estudo da variabilidade do torque. Também foi adicionado um segundo modelo de gerador de força, que consegue reproduzir melhor as características temporais dos abalos das unidades motoras. Adicionalmente, um modelo do tipo Hill também foi modificado para ser ativado pelo conjunto de motoneurônios do simulador ReMoto. Novas simulações foram feitas com a nova versão do simulador (adaptada a dados de humanos) e os resultados foram condizentes com os dados experimentais (variabilidade do torque e do eletromiograma), indicando que os modelos no simulador são uma representação razoável do que acontece no ser humano. / The muscle force variability, usually in a constant and isometric force task, has been studied both experimentally and using computational tools. However, most studies using computer simulations have been made on tasks that use only one muscle, usually in the hand. As far as is known, no study has analyzed, either theoretically or experimentally, the overall behavior of the torque variability during plantar flexion. Therefore, this work aims to study the plantar flexion torque variability by means of mathematical models and simulations, comparing the results with those obtained in human experiments carried out locally. A first attempt was made using a Hill-type muscle contraction model activated by the electromyogram obtained from each of the three triceps surae muscles. This approach was not successful in terms of reproducing the torque variability results obtained from humans, although it estimated well the average value of plantar flexion torque. This inability to reproduce the torque variability found in experimental data was probably due to the information loss in the electromyogram of the spike times of motoneurons. In a second approach, the firing of individual motoneuron were obtained from a neuromuscular simulator developed locally, called ReMoto, capable of providing the spike times of all motoneuron models that activate each muscle and the respective muscle force. The latter is generated in the simulator from the forces generated by each motor unit that composes the muscle. However, the ReMoto original version was almost completely parameterized using data from cats and, hence, it was necessary to modify various parameter values (such as motor unit twitchs and action potential amplitudes) and models (such as the recruitment threshold and force saturation) before using the simulator to study torque variability in humans. Besides the second order twitch model already implemented in the original version of the simulator, two other models were implemented in this work. One was a more refined twitch model and the second was a Hill-type model modified to be activated by the ReMoto simulator motoneuron pool. New simulations were run with the new version of the simulator (adapted to human data) and the fittings to the experimental data (torque and electomyogram envelope variability) were good, suggesting that the models in the simulator are a reasonable representation of what occurs in the living human being.

Sequences of stereotyped actions are central to the everyday lives of humans and animals, from the kingfisher's dive to the performance of a piano concerto. Lashley asked how neural circuits managed this feat nearly 6 decades ago, and to this day it remains a fundamental question in neuroscience. Toward answering this question, vocal performance in the songbird was used as a model to study the performance of learned, stereotyped motor sequences. The first component of this work considers the song motor cortical zone HVC in the zebra finch, an area that sends precise timing signals to both the descending motor pathway, responsible for stereotyped vocal performance in the adult, and the basal ganglia, which is responsible for both motor variability and song learning. Despite intense interest in HVC, previous research has exclusively focused on describing the activity of small numbers of neurons recorded serially as the bird sings. To better understand HVC network dynamics, both single units and local field potentials were sampled across multiple electrodes simultaneously in awake behaving zebra finches. The local field potential and spiking data reveal a stereotyped spatio-temporal pattern of inhibition operating on a 30 ms time-scale that coordinates the neural sequences in principal cells underlying song. The second component addresses the resilience of the song circuit through cutting the motor cortical zone HVC in half along one axis. Despite this large-scale perturbation, the finch quickly recovers and sings a near-perfect song within a single day. These first two studies suggest that HVC is functionally organized to robustly generate neural dynamics that enable vocal performance. The final component concerns a statistical study of the complex, flexible songs of the domesticated canary. This study revealed that canary song is characterized by specific long-range correlations up to 7 seconds long-a time-scale more typical of human music than animal vocalizations. Thus, the neural sequences underlying birdsong must be capable of generating more structure and complexity than previously thought.

abstract: The ability to plan, execute, and control goal oriented reaching and grasping movements is among the most essential functions of the brain. Yet, these movements are inherently variable; a result of the noise pervading the neural signals underlying sensorimotor processing. The specific influences and interactions of these noise processes remain unclear. Thus several studies have been performed to elucidate the role and influence of sensorimotor noise on movement variability. The first study focuses on sensory integration and movement planning across the reaching workspace. An experiment was designed to examine the relative contributions of vision and proprioception to movement planning by measuring the rotation of the initial movement direction induced by a perturbation of the visual feedback prior to movement onset. The results suggest that contribution of vision was relatively consistent across the evaluated workspace depths; however, the influence of vision differed between the vertical and later axes indicate that additional factors beyond vision and proprioception influence movement planning of 3-dimensional movements. If the first study investigated the role of noise in sensorimotor integration, the second and third studies investigate relative influence of sensorimotor noise on reaching performance. Specifically, they evaluate how the characteristics of neural processing that underlie movement planning and execution manifest in movement variability during natural reaching. Subjects performed reaching movements with and without visual feedback throughout the movement and the patterns of endpoint variability were compared across movement directions. The results of these studies suggest a primary role of visual feedback noise in shaping patterns of variability and in determining the relative influence of planning and execution related noise sources. The final work considers a computational approach to characterizing how sensorimotor processes interact to shape movement variability. A model of multi-modal feedback control was developed to simulate the interaction of planning and execution noise on reaching variability. The model predictions suggest that anisotropic properties of feedback noise significantly affect the relative influence of planning and execution noise on patterns of reaching variability. / Dissertation/Thesis / Ph.D. Bioengineering 2012

Cognitive and motor impairments have been identified as signs following a concussion which may compromise the performance of everyday tasks or physical activities. However, little work has been done in the adolescent population using laboratory based measurements of attention or balance control to identify recovery from concussion. Therefore, the purpose of this dissertation was to prospectively and longitudinally observe how individuals who have sustained a concussion recover on measures of attention and gait balance control in comparison to individually matched, healthy control subjects from within 72 hours of injury up to two months following injury. Individuals were identified as sustaining a concussion by healthcare professionals and began participation in the study within 72 hours of injury. They then returned to the laboratory at approximately 1 week, 2 weeks, 1 month, and 2 months post-injury. Control subjects were individually matched by sex, age, height, and weight and tested in similar time increments. Attentional abilities were measured via multiple computerized testing assessments, and gait balance control was measured with whole-body motion analysis. The results indicated that following concussion, adolescents display deficits in conflict resolution ability, task switching ability, and gait balance control during dual-task walking for a time period of up to two months following injury in comparison to a matched control group. During dual-task walking, the complexity of the cognitive task performed may affect adolescents with concussion to a greater degree than matched control subjects. Adolescents also displayed regressions to gait stability recovery following their return to physical activities. Finally, adolescents with concussion displayed greater gait balance control deficits than young adults with concussion throughout the two months of testing when each group was compared to a respective healthy control group. Results from this dissertation indicate that concussion affects cognitive and motor functions in adolescents, who display deficits throughout two months post-injury. Computerized attentional tests and dual-task dynamic balance control assessments represent a multifaceted approach to concussion management and may provide another assessment battery for healthcare professionals to utilize in order to identify recovery following concussion. This dissertation includes previously published/unpublished co-authored material.

1.1 Background This thesis is presented as an investigation into the movement integration, performance processes and effects of anxiety on the skill acquisition of individuals diagnosed with Down syndrome or DS as it will be referred to in this thesis (a full description of this genetic condition is presented in the thesis introduction). The investigation of several features of motor control and performance pressure in individuals with DS is carried out through several related research projects which will be rationalised and outlined throughout. In both everyday life and in sporting situations, people are required to perform tasks quickly and accurately and these tasks vary in complexity. Some of these actions consist of one segment movements (e.g. turning on a light switch), whilst other actions have multiple segments (e.g. making a cup of tea) and the need to be fast whilst maintaining a high degree of accuracy is very important. Therefore understanding the basic principles behind these actions in individuals with DS and how performance pressure may affect speed and accuracy of movements will not just have theoretical implications, but also practical importance such as designing practice protocols to enhance functional independence. Motor skill control, learning and performance are imperative for everyday activities such as signing one’s name, dressing oneself and personal hygiene. The capability to perform these motor skills with or without support is of the upmost importance for individuals with DS. Discovering new channels of enhancement in motor skill control, learning and performance for individuals with DS is extremely important and vital step on the pathway to improving functional independence for personal and professional gains. 1.2 Outline of thesis This thesis attempts to investigate the issues relating to the programming of movements and the affects of anxiety on the motor skill learning of individuals with DS. The first experimental chapter focuses on the underlying mechanisms responsible for the planning, control and integration of multiple target aiming extension movements in individuals with DS. The aim of this chapter was utilise to the One Target Advantage (OTA) phenomenon in sequential extension movements to see if individuals with DS utilise similar movement planning and control strategies to typically developing (TD) individuals and individuals with an undifferentiated intellectual disability (UID). The second experimental chapter was designed to further understand the control of multiple directional movement actions in the DS population and the possible central and peripheral movement deficits. This experimental chapter aims to examine both the directional requirement of the second movement together with the effects of practice on the OTA phenomenon in persons with DS. Specifically, as in the first experimental chapter, we compare single-target movements with two-target extension sequences when the two-target responses are performed with a single arm and when there is a switch between the arms used to execute the first and second movement segments. However, in this chapter we also include sequences where the second movement in the sequence requires a reversal in direction to that of the first movement. The purpose of the third experimental chapter was to investigate the effects of environmental characteristics outside of those associated with the number of targets within a sequence. Specifically, the effects of performance pressure on the speed and accuracy of the movements of persons with DS. 1.3 Thesis format This thesis consists of a review of the literature, three research papers and a general discussion. All three manuscripts were written as stand-alone research articles and have been or are currently being prepared to be submitted for publication in international disability research journals. For consistency, all manuscripts have been written in the style of the American Psychological Association Publication Manual (Deckers, 2001) and the current recommendations adopted by the School of Sport, Health and Exercise Sciences, Bangor University for thesis preparation. For this purpose, all illustrations are numbered consecutively and citations are included in a single section at the end of this thesis. For ease of reading, all abbreviations are defined at their first appearance within each chapter of the thesis. Any contribution of co-authors is detailed in the ‘acknowledgements’ section of this thesis. All experimental chapters of this thesis are independent but linked, therefore at times there may be a necessary overlap in content between chapters.

Made available in DSpace on 2014-06-11T19:34:58Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-01-23Bitstream added on 2014-06-13T20:05:58Z : No. of bitstreams: 1 amorim_cf_dr_guara.pdf: 1558739 bytes, checksum: cf912517af4f1c4f658892c975ee2aa1 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O controle postural é um fator determinante na execução de gestos funcionais que necessitam de um alto desempenho da coordenação motora, como por exemplo, nas atividades esportivas. Neste presente trabalho foi abordada a modalidade esportiva do futebol, e de forma mais específica, o gesto técnico do chute. Neste sentido, o objetivo deste trabalho foi de investigar o equilíbrio dinâmico durante o chute futebolístico por meio de um sistema de análise com uma tarefa controlada. O sistema proposto foi constituído por um dispositivo disparador vertical de bola, alvo de acerto, sistema de aquisição de sinais com eletromiografia, acelerômetria, registro do instante do acionamento do disparador, e por uma plataforma de força. A amostra foi constituída por 11 atletas profissionais de futsal, os quais realizaram a tarefa de vinte e cinco chutes ao alvo com a bola em movimento vertical. Para análise dos dados foi proposta a identificação e análise do comportamento dos sinais dos músculos Glúteo média (GM), Tibial anterior (TA), Fibular longo (FL) e Vasto lateral (VL), em relação às variáveis estabilométricas do equilíbrio postural no pré-chute, durante o chute e após-chute. Foram apresentados os gráficos das médias das variáveis estabilométricas: posição média, desvio padrão, deslocamento total, amplitude, velocidades, freqüências médias e freqüências medianas na direção ântero-posterior (AP) e médio-lateral (ML), centro de pressão (COP) e respectiva direção de oscilação, desenvolvidas durante a execução da tarefa controlada do chute. Os resultados apresentaram o comportamento das médias dos valores RMS (root mean square) dos músculos glúteo médio (GL), tibial anterior (TA), fibular longo (FL) e vasto lateral (VL) no pré-chute, durante o chute e pós-chute em relação a análise postural através do COP... / Postural control is a determining factor in the execution of functional movements that require a high performance of the motor control coordination, such as sporting activities. In this study the soccer sports activity was chosen, and more specifically, the technical movement of the kick. The objective this study was to investigate the postural sway through the kick’s movement control. A vertical ball shooting machine (VBS) with an active target was especially developed to measure the effectiveness of the kick. This system was synchronized with electromyographic signal, accelerometer and force platform in order to recognize the movement. Eleven professional athletes of soccer kicked the ball twenty-five times on target using the VBS system by EMG System do Brasil. Data analysis was proposed for identification and correlation of the signal behavior of the middle gluteus muscle (GM), tibialis anterior (TA), peroneus longus (FL) and vastus lateralis (VL) in relation stabilometric variables of postural sway before the kick, during the kick and after the kick. It was analysed of stabilometric variables: the mean position, standard deviation, total displacement, amplitude, speed, median frequencies in the anteroposterior (AP) and mediolateral (ML) of the center of pressure (COP ) and direction of oscillation during the controlled kick. The results showed the same trends in the behavior of the RMS (root mean square) of the gluteus medius muscle (LG), tibialis anterior (TA), peroneus longus (FL) and vastus lateralis (VL) before the kick during the kick and after the kick. This was also observed in the analysis of the variables stabilometric, standard deviation, speed, median frequency in anteroposterior (AP) and mediolateral (ML). Considering the results of this study, analysis of the behavior of EMG signals of the muscles involved in... (Complete abstract click eletronic access below)