Effect of force magnitude of touch on the components of postural sway.

BACKGROUND: Lightly touching the tip of the index finger on an external surface reduces the postural sway during upright standing due to the additional somatosensory information provided by the touch to the postural control system. But when the individuals apply more force, it provides more mechanical support. However, because most of the studies investigated only two levels of force, whether the control mechanisms of postural sway are affected by the different force levels was unknown. RESEARCH QUESTION: To examine the influence of the magnitude of force (up to 1, 2, 4, 6 or 8 N) applied to the touch bar on the mechanisms used to control the postural sway during quiet standing with eyes open or closed. METHODS: Ten young right-handed adults stood for 35 s on a force platform, with feet apart, while touched a rigid bar with different force levels with eyes open or closed. The amplitude and velocity of the center of pressure and its components, Rambling and Trembling trajectories, respectively, related to more supraspinal and spinal control mechanisms, were assessed. RESULTS: The touch reduced all trajectories, mainly of the Rambling component and with closed eyes. There was a floor effect of the touch force as amplitudes and velocities were minimal at 4 N of force. SIGNIFICANCE: The component of postural sway under the supraspinal neural control is more affected by different force magnitudes applied to the touch bar.

Target height affects the symmetry of the postural adjustments after (but not prior) the onset of reaching movements in upright standing.

The present study aimed to investigate the influence of target height on the symmetry and amplitude of the postural adjustments assessed by the displacements of the center of pressure (COP) before and during the unilateral, arm movements in the upright position. Thirteen young, right-handed adults stood with each foot on one force platform and reached a target placed at one of three heights displayed on a monitor screen. The performance of the right arm movements (movement time and radial error), amplitude of the COP displacements of each lower limb and the percentage of body weight loading on the right lower limb before and during the reaching movements were compared across target heights conditions. Postural adjustments were symmetrical prior but asymmetrical after movement onset. Effect of target height was observed on the postural adjustments before and during the movements (i.e., amplitudes of the COP displacements increased for the higher target), mainly for the right limb. The arm performance was similar across target heights. The findings of the present study suggested that postural adjustments are dependent on the target heights to ensure success in the arm movements.

Individuals' perception about upper limb influence on participation after stroke: an observational study.

Background Stroke can compromise upper limb performance and influence the individual's participation in real life situations. Objective To investigate how components of body function and activity affect the individuals' self-perception of their participation after stroke. Methods In this observational study, the International Classification of Functioning, Disability and Health was used as model. Body function was assessed by palmar grip and pinch strength; Ashworth modified scale; Fugl-Meyer scale; and Motor-Free Visual Perception Test. The Purdue Pegboard Test and the aiming movement performance measured the activity. Upper limb participation was analyzed by the Hand Function domain of the Stroke Impact Scale (SIS). Thirty-four individuals after chronic stroke were divided into two groups, according to their Hand function SIS scores (severe and non-severe). Differences between groups were analyzed. Relationships between individual variables and the SIS score were verified. A regression model was proposed. Results Strength and the Fugl-Meyer scale score were greater for the non-severe group. Muscle tone was greater for the severe group only in the wrist flexors. None of the activity variables differed between groups. The upper limb Fugl-Meyer score was able to predict 79% of the individuals in SIS Hand Function groups. Conclusion Sensory-motor impairment, as measured by the upper limb Fugl-Meyer scale, can explain the influence of the upper limbs on participation in the individuals' perception.

Ipsilesional upper limb performance in stroke individuals: relationship among outcomes of different tests used to assess hand function / Relação entre o desempenho em diferentes testes de função manual de indivíduos pós acidente vascular encefálico: avaliação do membro ipsilesional

Abstract Introduction: Stroke individuals have sensorimotor repercussions on their ipsilesional upper limb. Therefore, it is important to use tests that allow an adequate assessment and follow-up of such deficits. Physical and occupational therapists commonly use maximal grip strength tests to assess the functional condition of stroke individuals. However, one could ask whether a single test is able to characterize the hand function in this population. Objective: The aim of this study was to investigate the relationship among outcomes of different tests frequently used to describe the function of the hand in the ipsilesional upper limb of stroke individuals. Methods: Twenty-two stroke individuals performed four hand function tests: maximal handgrip strength (HGSMax), maximal pinch grip strength (PGSMax), Jebsen-Taylor Hand Function Test (JTHFT) and Nine Hole Peg Test (9-HPT). All tests were performed with the ipsilesional hand. Pearson's correlation analyses were performed. Results: the results indicated a moderate and positive relationship between HGSMax and JTHFT (r = 0.50) and between JTHFT and 9-HPT (r = 0.55). Conclusion: We conclude that the existence of only moderate relationships between test outcomes demonstrates the need to use at least two instruments to better describe the ipsilesional hand function of stroke individuals.

Resumo Introdução: Indivíduos que sofreram um acidente vascular encefálico (AVE) apresentam repercussões sensoriomotoras em membro superior ipsilesional, se tornando importante a utilização de testes que possibilitem a avaliação e o acompanhamento adequado de tais déficits. Profissionais da reabilitação, como fisioterapeutas e terapeutas ocupacionais, comumente utilizam testes de força de preensão máxima para avaliar as condições funcionais de indivíduos após um AVE. Porém, será que apenas um teste é capaz de caracterizar a funcionalidade das mãos? Objetivo: O objetivo desse estudo foi examinar a relação do desempenho entre testes comumente utilizados para descrever a função manual do membro ipsilesional de indivíduos que sofreram um AVE. Métodos: Vinte e dois indivíduos pós AVE realizaram quatro testes: força de preensão palmar máxima (FPPMax), força de preensão digital máxima (FPDMax), teste de função manual Jebsen-Taylor (TFMJT) e teste dos nove pinos nos buracos (9-PnB). Todos os testes foram realizados com a mão ipsilesional. Foram realizados testes de correlação de Pearson entre os resultados obtidos em cada teste. Resultados: Os resultados indicaram uma relação positiva e moderada apenas entre TFMJT e FPPMax (r = 0,50) e entre o desempenho no TFMJT e no teste dos 9-PnB (r = 0,55). Conclusão: Conclui-se que a existência de relações de fraca a moderada demonstra a necessidade de utilização de pelo menos dois instrumentos, para que se possa descrever melhor a funcionalidade das mãos de indivíduos pós AVE.

Análise biomecânica do tronco e pelve em exercícios do método pilates: revisão sistemática / Análisis biomecánico del tronco y de la pelvis en ejercicios del método pilates: revisión sistemática / Biomechanical analysis of the trunk and pelvis during pilates method exercises: systematic review

RESUMO O método pilates é atualmente utilizado na reabilitação e na prática de atividade física. Alguns estudos investigaram sua eficácia no tratamento de condições específicas, mas informações sobre a avaliação biomecânica durante a realização dos exercícios ainda são escassas. Portanto, o objetivo deste estudo foi realizar uma revisão sistemática de estudos observacionais com avaliação biomecânica durante os exercícios baseados no método pilates. A busca foi realizada nas bases de dados Embase, CINAHL, Web of Science, SPORTDiscus e PubMed. Alguns dos termos relacionados à biomecânica e pilates, como "cinemática" e "eletromiografia", foram interligados por or/and. A análise da qualidade metodológica e da captação do sinal eletromiográfico foi baseada nas diretrizes do STROBE (Strengthening the Reporting of Observational Studies in Epidemiology) e dos Standards for Reporting EMG Data do ISEK, respectivamente. Dos 14 estudos incluídos na revisão sistemática, apenas um utilizou o desenho de estudo transversal do tipo caso e controle. Exercícios de pilates realizados no solo e os músculos multífidos foram os mais avaliados, utilizando principalmente a avaliação eletromiográfica. Os resultados dos estudos permitiram observar que os músculos multífidos foram os mais ativados em alguns exercícios do método pilates e que a ativação muscular é dependente da posição do praticante e da posição das molas. Os 14 estudos publicados possuem qualidade metodológica satisfatória, mas a maioria deles possui descrição incompleta dos registros eletromiográficos. Assim, podemos sugerir que a mudança de posicionamento do praticante/molas e a escolha dos exercícios interferem diretamente na ativação muscular durante a realização de exercícios.

RESUMEN La acumulación de la grasa torácica puede contribuir a la reducción de la movilidad torácica (MT) con disminución del volumen pulmonar. También las alteraciones de la MT pueden ocurrir en el envejecimiento, debido a la progresiva calcificación de las articulaciones implicadas en los movimientos respiratorios y a la reducción de los espacios intervertebrales. Este estudio tuvo el objetivo de verificar la influencia de la edad, de las características antropométricas y de la distribución de grasa corporal en conductas de la MT de mujeres, así como verificar cuál de las variables es la más relevante para la MT. Se trata de un estudio transversal, del cual participaron 100 mujeres con edades entre 25 y 75 años y con índice de masa corporal (IMC) entre 18,5 y 55kg/m2. Se midieron las circunferencias del cuello (CC), de la cintura, de las caderas y la relación entre cintura/cadera. Se evaluó la MT a través de la cirtometría torácica en los niveles axilar y xifoides y, tras realizarse las tres mediciones, se determinó la MT por la diferencia entre el valor más grande obtenido en la inspiración y el menor valor en la espiración. Se emplearon los test de correlación y de regresión lineal múltiple. Mediante las correlaciones significativas, los resultados demostraron que la MT disminuye debido al aumento de edad y a la obesidad. La CC tuvo mayor influencia (16,60%) bajo la MT en el nivel axilar y el IMC en el nivel xifoides (18,16%). Se concluyó que la MT redujo con el envejecimiento y la obesidad, y que la acumulación de grasa en el cuello y el aumento del IMC son los factores que más influyen en el comprometimiento de la MT de mujeres.

ABSTRACT The pilates method is currently used in the rehabilitation and practice of physical activity. Some studies have investigated the effectiveness of the pilates method in the treatment of specific conditions, but information about the Biomechanical evaluation during the exercises are still scarce. Therefore, the purpose of this study was to conduct a systematic review of observational studies with biomechanical evaluation during the exercises based on the pilates method. The search was conducted based on data of the EMBASE, CINAHL, Web of Science, SPORTDiscus and PubMed databases. Some of the terms related to Biomechanics and pilates, as "cinematic" and "electromyography", were connected by or/and. The analysis of the methodological quality and electromyographic signal capture was based on the guidelines of STROBE (Strengthening the Reporting of Observational Studies in Epidemiology) and Standards for Reporting EMG Data of ISEK, respectively. Of the 14 studies included in a systematic review, only one cross-sectional study design was used of the case and control type. pilates exercises carried out in the soil and multifidus muscles were the most evaluated, using mainly the electromyographic evaluation. The results of the studies made it possible to observe that the multifidus muscles were the most used in some exercises of the pilates method and muscle activation is dependent upon the position of the practitioner and the position of the springs. The 14 studies published have a satisfactory methodological quality, but most of them have incomplete description of electromyography records. Thus, we can suggest that the change of positioningof the practitioner/springs and the choice of exercises interfere directly in the muscle activation during exercises of the pilates method.

Uncertainty in aiming movements and its association to hand function / Incerteza de movimentos dirigidos ao alvo e sua associação com a função manual / La incertidumbre de movimientos dirigidos a la diana y su asociación con la función manual

The purpose of this study was to analyze the influence of the uncertainty of target location on the planning and execution of aiming movements performed towards the ipsilateral and contralateral directions by the right and left upper limbs. In addition, the association between the performance of aiming movements and the performance of functional manual tasks was investigated. Two tasks were proposed: with prior knowledge of the movement direction (simple reaction time) or not (choice reaction time). The grip strength and manual dexterity were measured. The choice option in response (i.e. uncertainty) influenced planning of the aiming movements, but not its execution, while movements performed towards the contralateral direction were worse in execution as compared to the ipsilateral direction. Manual dexterity was significantly correlated with reaction times, while the performance during movement execution was significantly correlated with handgrip/pinch strength.

O objetivo desse estudo foi avaliar a influência da incerteza da localização do alvo no planejamento e execução de movimentos dirigidos ao alvo realizados para as direções ipsilateral e contralateral pelos membros superiores direito e esquerdo. Em adição, a associação entre o desempenho do movimento dirigido ao alvo e o desempenho em tarefas manuais funcionais foi investigada. Duas tarefas foram propostas: com o conhecimento prévio da direção do movimento (tempo de reação simples) ou não (tempo de reação de escolha). Foram avaliadas a força de preensão palmar e a destreza manual. A opção de escolha na resposta (ex. incerteza) influenciou o planejamento do movimento dirigido ao alvo, mas não a sua execução, enquanto os movimentos realizados para a direção contralateral apresentaram pior execução quando comparados à direção ipsilateral. Destreza manual foi significativamente correlacionada com tempos de reação, enquanto o desempenho durante a execução do movimento foi significativamente correlacionado com forças de preensão/pinça.

El propósito de este estudio fue evaluar la influencia de la incertidumbre ubicación de la diana en la planificación y ejecución de movimientos dirigidos a la diana realizado por direcciones ipsilateral y contralateral por los miembros superiores derecho e izquierdo. Además, se investigó la asociación entre el rendimiento de movimiento dirigido a la diana y el rendimiento de la mano para tareas funcionales. Se propusieron dos tareas: con el conocimiento previo de la dirección del movimiento (tiempo de reacción simple) o no (tiempo de reacción del elección). Se evaluó la fuerza de prensión y la destreza manual. La opción de elección en responder (Incertidumbre por ejemplo.) influido en la planificación del movimiento dirigido a la diana, pero no su aplicación, mientras que el movimiento de la dirección contralateral tuvo un peor rendimiento en comparación con la dirección ipsilateral. La destreza manual se correlacionó significativamente con los tiempos de reacción, mientras que el rendimiento durante la realización del movimiento se correlacionó significativamente con la fuerza de prensión / pinzas.

Ipsilesional arm motor sequence performance after right and left hemisphere damage.

Aiming movements are part of daily activities but the brain hemispheres' role in targeted aiming sequential movements is not fully clear. Start and execution of discrete and sequential tasks toward targets were analyzed in 10 individuals with left-hemisphere damage, 10 right-hemisphere-damaged, and 10 healthy ones. Arm movements were performed over a digitizing tablet, following stimuli on a monitor, from initial position toward right and left-positioned targets. Poststroke individuals used their ipsilesional arm and healthy individuals, both arms. Right-hemisphere-damaged individuals showed higher reaction time and left-hemisphere-damaged individuals, lower smoothness. Due to spatial demand of tasks, the right hemisphere played a major role in movement planning, while the left, in movement execution.

Uso da informação somatossensorial adicional no controle postural: efeito da dominância manual / The use of additional somatosensory information on postural control: effect of handedness

Buscamos com o presente estudo investigar o efeito da dominância manual e da visão no uso da informação somatossensorial adicional fornecida pelo toque suave no controle postural. Quinze adultos jovens e destros permaneceram em pé sobre uma plataforma de força com a) olhos abertos ou fechados e b) braços ao lado do corpo ou o dedo indicador direito ou esquerdo tocando a barra fixa. A área do centro de pressão (CP), amplitude e velocidade médias do CP nas direções anteroposterior e médio-lateral foram avaliadas. Os resultados indicaram uma redução nas medidas nas condições de toque e aumento com os olhos fechados, exceto quando o toque foi realizado com dedo indicador direito. A força máxima foi maior para a mão direita, enquanto a sensibilidade cutânea e as forças aplicadas à barra foram similares entre os hemicorpos. Esses resultados sugerem um efeito da dominância manual e visão no uso da informação somatossensorial adicional no controle postural...

In this study we investigated the effect of handedness and vision on the use of additional somatosensory information provided by the light touch in postural control. Fifteen right-handed, young adults quietly stood on a force plate with a) eyes open or closed and b) arms hanging along the body or with the right or left index finger in contact with a rigid bar. We assessed the center of pressure (CP) area and CP mean sway amplitude and velocity in anterior-posterior and medial-lateral directions. The results revealed a reduction of these measures in the touch conditions and increase with the eyes closed, except when the touch was performed with right index fingertip. The grip strength was greater for the right hand, while the cutaneous sensitivity and the forces applied on the bar were similar between the two sides of the body. These results suggested an effect of the handedness and vision in the use of additional somatosensory information on the postural control...

Effects of target location and uncertainty on reaching movements in standing position / Efeitos da localização do alvo e da incerteza em movimentos de alcance na postura ereta / Los efectos de la ubicación de la diana y la incertidumbre en los movimientos de alcance en la posición vertical

The effects of target location and uncertainty of target position on reaching movements while standing were investigated. Ten healthy, right-handed adults stood facing a 17'' touchscreen. They were instructed to press with their right index fingertip a push bottom and touch the center of the target displayed on the screen after it was lighted on, moving quickly their arm. The target was shown either ipsi- or contralateral to the right arm and either in a certain or uncertain position. Reaction time (RT), movement time (MT), and radial error (RE) were assessed. Results revealed shorter RT (≈ 35 ms) and smaller RE (≈ 0.19 cm) for certain than for uncertain condition and slightly longer RT (≈ 8 ms) and MT (≈ 18 ms) for reaches towards the contralateral target. In conclusion, the findings of this study showing the effect of uncertainty of target location as well as target position are also applied to arm reaching in standing position.

Os efeitos da localização do alvo e da incerteza quanto à posição do alvo em movimentos de alcance foram investigados. Dez adultos permaneceram em pé em frente a um monitor sensível ao toque. Eles foram instruídos a pressionar com o dedo indicador direito um interruptor e tocar o centro do alvo apresentado no monitor após ele acender, movendo o membro superior rapidamente. O alvo foi mostrado ipsi ou contralateralmente e os participantes tinham ou não certeza sobre a posição do alvo. O tempo de reação (TR) e movimento (TM) e o erro radial (ER) foram avaliados. Os resultados revelaram menor TR (≈35 ms) e ER (≈0,19 cm) para a condição de certeza e maiores TR (≈8 ms) e TM (≈18 ms) para os moimentos ao alvo contralateral. Concluindo, esses achados mostraram que os efeitos da incerteza da localização e a posição final do alvo podem ser aplicados para movimentos de alcance na posição ereta.

Los efectos de la ubicación de la diana y la incertidumbre acerca de la posición de la diana en los movimientos de alcance fueron investigados. Diez adultos sanos y diestros estaban frente a una pantalla táctil de 17''. Se les instruyó para presionar un interruptor con el dedo índice derecho y tocar el centro de la diana que aparece en la pantalla después de haber sido iluminado, moviéndo rápidamente su miembro superior. La diana fue mostrada ya sea ipsi o contralateralmente y los participantes tenían o no certidumbre sobre la posición de la misma. El tiempo de reacción (TR), el tiempo de movimiento (TM), y el error radial (ER) fueron evaluados. Los resultados revelaron ser más cortos TR (≈ 35 ms) y RE menor (≈ 0,19cm) en la condición de certeza y mayores TR (≈ 8 ms) y TM (≈ 18 ms) en los movimientos hacia la meta contralateral. En conclusión, los hallazgos de este estudio que muestra los efectos de la incertidumbre de la ubicación de la diana, así como la posición de la diana se aplican también a movimientos de alcance en la posición erecta.