This project was funded by, in part, by start-up funds from Wayne State University to M.H. Malek.

Todos os procedimentos foram aprovados pelo Conselho de Revisão Institucional da Universidade de Seres Humanos. 1. Preparação de Perna do Participante <ol><li> Já o participante ordenadamente arregaçar as calças curtas para a perna desejado. Em seguida, cole os calções para que os quadríceps femoral grupo muscular está exposta e desenhar uma linha ao redor da área do participante precisa fazer a barba. </li><li> IMPORTANTE: Tenha o participante raspar a perna antes do teste, em vez de no dia anterior, pois isso garante que não há restolhos que possam interferir com o sinal de EMG. </li><li> Uma vez que o participante tenha terminado raspar a área desejada da perna, limpar a área raspada com álcool para garantir que não haja vestígios do gel de barbear (ou creme) que podem interferir com o sinal de EMG. </li></ol> 2. Medição de Perna da colocação de eléctrodos <ol><li> A fim de colocar o eletrodo EMG no músculo vasto lateral, fazer o fomedições llowing <ol><li> Já o participante estar em linha reta de frente para o pesquisador. </li><li> Localize a espinha ilíaca anterior superior (EIAS) eo lado lateral da patela. A ASIS é o osso do quadril; palpar-lo, colocando o lado em ambos os lados do abdómen abaixo do umbigo. </li><li> Com uma fita métrica, medir a distância entre os dois locais identificados acima e tomar 2/3 de que o valor na linha de ASIS para o lado lateral da patela. Nota: Para mais informações a respeito da colocação de eletrodos EMG pode ser encontrado no SENIAM (eletromiografia de superfície para a avaliação não invasiva dos músculos) URL: http://www.seniam.org/ </li></ol></li></ol> 3. colocação dos eletrodos EMG <ol><li> Após a localização do vasto lateral foi identificada, adoptar os eletrodos EMG (a maioria dos pesquisadores usar comercialmente disponíveis descartáveis ​​eletrodos Ag Ag-Cl) e coloque sobre o vasto lateral, sem retirar o adesivo shield. Em seguida, com uma marca da pena da área onde a porção de gel do eléctrodo entra em contacto com o músculo. Assegure-se que a distância intereletrodos é 20 milímetros centro-a-centro. </li><li> Utilizar um pedaço de uma lixa (60 grosseiro) para raspar suavemente estas duas áreas para remover a camada superficial da pele. Durante este tempo, pedir ao participante o seu nível de desconforto. Pare de abrasão quando o participante indica a área é quente. </li><li> Limpe as áreas desgastadas com uma toalha que é umedecido com álcool ou um algodão embebido em álcool. Permitir que a zona da perna para secar antes da colocação dos eléctrodos de EMG. </li><li> Coloque os eletrodos EMG sobre os sites que foram desgastados (Figura 2). Tome cuidado para não colocar os eletrodos na banda iliotibial (banda de TI). Peça ao participante para contrair os músculos quadríceps femoral, a fim de palpar o vasto lateral. Coloque os eletrodos no músculo para garantir que ele não está na faixa de TI. Nota: Se os eletrodos sobre a banda de TI, o sinal você está EMGld ser atenuado quando o participante é convidado a um máximo de contrato. </li><li> Coloque o eletrodo de referência (3º eléctrodo) em um local de ligação ósseo tais como a ASIS, portanto, não interfere com os movimentos dos membros inferiores durante o exercício. </li></ol> 4. Verificar o Sinal EMG <ol><li> Antes de iniciar o teste de exercício, verifique a impedância intereletrodos. Nota: Esta etapa é fundamental, porque se o sinal tem muito barulho, em seguida, os dados EMG coletados durante o teste de esforço será inválido. <ol><li> Já o participante sentar em uma cadeira e se conectar a EMG leva a seus respectivos eletrodos ligados a perna do participante. </li><li> Neste ponto, tem o participante relaxar a sua perna, tendo nenhuma tensão no músculo. Em seguida, após cerca de 30 segundos de relaxamento, o participante tem maximamente contrair seus músculos do quadríceps femoral durante 5 segundos e, em seguida, voltar a ser completamente relaxado. </li><li> Ao executar a tarefa umabove (passo 4.1.2), gravar o sinal EMG participantes no computador. </li><li> Certifique-se de que a impedância intereletrodos é &lt;2.000 ohms. Além disso, se um voltímetro está disponível no laboratório, em seguida, verifique o ruído da linha de base e manter abaixo de 5 mV. Além disso, defina a frequência de amostragem em 1.000 Hz. </li></ol></li></ol> 5. Constituição cicloergômetro <ol><li> Depois de verificar a impedância intereletrodos, tem o movimento participante da cadeira para a bicicleta ergométrica. </li><li> Já a participante em pé ao lado da bicicleta ergométrica e elevar seu joelho até a coxa é paralelo ao solo. Em seguida, ter o participante mantenha esta posição e ajustar a altura do assento para coincidir com a mesma altura que a coxa do participante. </li><li> Depois disso, o participante tem sentar no banco bicicleta ergométrica e depois pedalar algumas vezes enquanto perguntando-lhes se eles estão confortáveis ​​com a altura do assento. Se necessário, ajuste a altura do assento. </li><li> Certifique-se de that pernas do participante estão perto extensão completa com uma ligeira curva (~ 5 °) nos joelhos durante cada revolução do pedal. </li><li> Antes de iniciar o teste, tem o participante usar um monitor de freqüência cardíaca polar de modo a que a frequência cardíaca pode ser documentado em todo o teste de esforço. </li></ol> 6. Realização do Threshold Protocolo EMG Fadiga <ol><li> Já o participante começar a pedalar e, gradualmente, aumentar a sua cadência de 70 revoluções / min. Em seguida, aumente a potência na bicicleta ergométrica a 50 W. </li><li> Já o ciclo de participante neste saída de energia para cerca de 2-3 min. Nota: Este é um exercício de baixa intensidade e servirá como o warm-up. </li><li> Após o período de aquecimento, aumentar a potência de 25 W cada 2 minutos até que o participante já não é capaz de manter a 70 rotações / min cadência ou solicita que o teste ser interrompido. Nota: Deve notar-se que, durante o teste de exercício, o sinal de EMG é gravado para 10seg épocas durante cada estágio 2 min para seg 10-20, 30-40, 50-60, 70-80, 90-100, 110-120 e 21. A maioria dos sistemas de EMG terá uma opção para definir a gravação automática no intervalo desejado. Assim, para cada fase, não deve ser de 6 ficheiros de dados. </li><li> Uma vez que o teste incremental concluiu, tem o participante realizar um fresco para baixo a 50 W. Verifique se o comprimento do arrefecimento corresponde com ter frequência cardíaca retorno do participante para o valor durante a fase de aquecimento. Monitorar isso verificando a freqüência cardíaca do participante utilizando o monitor de freqüência cardíaca polar. </li><li> Uma vez que o resfriamento for concluído, remova o EMG lidera e tem o participante sair da bicicleta ergométrica e retornar à cadeira. Em seguida, retire cuidadosamente os eletrodos EMG e limpe as áreas com uma toalha limpo umedecido com álcool ou um algodão embebido em álcool. </li></ol> 7. processamento do sinal de EMG <ol><li> Após a conclusão do teste, próCESS os ficheiros de dados brutos que EMG foram recolhidas durante o teste de exercício, de modo que os dados podem ser usados ​​para determinar o limiar de fadiga EMG. <ol><li> Executar o processamento do sinal EMG tanto com o software usado para coletar o sinal EMG ou software personalizado escrito usando várias plataformas, como MATLAB ou LabVIEW. </li><li> Filtrar os sinais EMG recolhidas utilizando um filtro passa-banda. Use uma configuração de 10 a 500 Hz. Nota: Isto altera a frequência do sinal de forma que os artefatos de baixa freqüência devido ao movimento dos condutores EMG (&lt;10 Hz), e artefatos de alta freqüência a partir do ambiente (&gt; 500 Hz), são removidos. Usar um filtro de corte de 60 Hz se houver qualquer interferência da fonte de alimentação do computador ou do sistema de EMG. </li><li> Uma vez que o sinal foi filtrado, determinar a amplitude do sinal por meio do cálculo do valor médio quadrático do sinal: Quadrado cada um dos pontos de dados, somá-los, dividir pelo número de pontos de dados, em seguida, tomar a raiz quadrada do valor resultante. Realizar estes cálculos utilizando o software acima mencionado. </li></ol></li></ol> 8. Determinação do Limiar de Fadiga EMG para cada participante <ol><li> Execute as seguintes etapas para cada participante. <ol><li> Após o sinal EMG foi processado; usar um programa estatístico (por exemplo: GraphPad Prism) e rotular a primeira coluna &quot;Time&quot; e as colunas subseqüentes com as saídas de potência utilizados para o ensaio. </li><li> Para cada saída de energia, preencher o valor correspondente amplitude EMG para cada intervalo de 20 segundos. </li><li> Para cada saída de energia, analisar o tempo (eixo dos xx) versus amplitude EMG (eixo y) em relação com a regressão linear para determinar se o declive da linha de regressão é significativa (p &lt;0,05) diferente de zero. </li><li> Depois de realizar a análises de regressão linear para todas as saídas de energia, identificar a potência máxima com uma inclinação não-significativa (p&gt; 0,05). </li><li> Em seguida, identificar o ldeves potência de saída com uma inclinação significativa (p &lt;0,05). </li><li> Uma vez que estas duas saídas de energia foram identificados, adicioná-los e dividir por 2; a potência de saída resultante é o limiar de fadiga EMG estimada. </li></ol></li></ol>

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The authors have nothing to disclose.

Nós aqui apresentamos um método para determinar a fadiga neuromuscular no quadríceps femoral para o exercício dinâmico. Este método proporciona uma abordagem simples e não invasivo para usando EMG de superfície. Além disso, a versatilidade deste método é que os investigadores podem adaptar a outros modos de exercício tal como tapete rolante 20. Teoricamente, para intensidades iguais ou abaixo do limiar de fadiga EMG o participante deverá ser capaz de sustentar o exerc...

Eletromiografia de superfície (EMG) é uma abordagem não-invasiva de estudar recrutamento motor unidade durante isométrica 1-3, 4-6 isocinético, ou contínua ação 7-10 muscular. A amplitude do sinal de EMG representa activação muscular, que consiste em o número de unidades motoras activado, a taxa de disparo das unidades motoras, ou ambos 11. O conceito do limiar de fadiga EMG é usado para indicar a maior carga de trabalho em que uma pessoa pode exercer indefinidamente sem um aumento na amplitude EMG 8. É importante discussão brevemente a origem do limiar de fadiga EMG. O estudo original de deVries et al. 12 envolveu um protocolo que consistiu de múltipla (geralmente 3-4) lutas descontínuas de trabalho, onde a amplitude EMG foi plotado em função do tempo para cada turno de trabalho. A saída de energia foi então representados graficamente em função dos coeficientes de inclinação da amplitude EMG contra rela tempo<html> lação e, em seguida extrapolados para inclinação zero (a intercepção-y) 12. Os autores 12 originalmente denominado protocolo que a capacidade de trabalho físico no limiar de fadiga (PWCFT). Em um outro estudo, deVries et al. 13 utilizaram ataques de trabalho descontínuos, mas utilizada a regressão linear para encontrar a primeira potência, que resultou em uma inclinação significativa para a amplitude EMG em relação relacionamento tempo. Os autores 13 também denominado que o protocolo PWCFT, criando alguma confusão na literatura. Em um artigo posterior, deVries et al. 14 modificado seu protocolo anterior 13 e desenvolveu um protocolo incremental contínua. A amplitude EMG foi representada graficamente contra o tempo para cada saída de potência e a PWCFT foi definido como a média da potência de saída mais elevada que resultou em nenhuma alteração na amplitude EMG ao longo do tempo e a saída de potência mais baixa, que resultou em um aumento na amplitude EMG ao longo do tempo 14 . ent &quot;&gt; Note-se que o termo PWC foi originalmente introduzido no final dos anos 1950 15,16 e é sinônimo de uma pletora de literatura (passado, presente e em diferentes países) examinando a capacidade aeróbica em uma determinada carga de trabalho 17. Além disso, o termo é usado na literatura ergonômico e industrial que se concentrar no dia-a-dia produtividade dos trabalhadores que exercem ação repetitiva durante os dias de 8 horas de trabalho, tais como indivíduos em uma fábrica de montagem 18. O limite de fadiga EMG termo foi inicialmente utilizado por Matsumoto e colegas 19 depois de o protocolo modificado deVries 12, onde a saída de potência contra coeficientes angulares de amplitude EMG contra relação de tempo estão representados graficamente e extrapolada para o ponto de inclinação zero. Mais recentemente, Guffey et ai. 20 e Briscoe et al. 8 utilizado o método de Vries et al. 14 e a terminologia de Matsumoto et all. 19 para definir operacionalmente o limiar de fadiga EMG. Avançando, recomendamos que o limiar de fadiga EMG termo ser usado. Assim, a amplitude EMG contra relação do tempo é representado para cada potência de saída e, em seguida, analisada utilizando análise de regressão linear (Figura 1). Para estimar o limite de fadiga EMG, a maior potência de saída com uma (p&gt; 0,05) inclinação não significativa e a saída de potência mais baixa com um aumento significativo (p &lt;0,05) declive é identificado e, em seguida, a média é calculada 14. Este protocolo é simples, conveniente e concluída dentro de 15-20 min. Além disso, a taxa incremental pode ser modulada com base no nível do indivíduo de atividade física habitual, e, portanto, tem aplicações potenciais em ambientes clínicos.

<table border="0" cellpadding="0" cellspacing="0">
	<tbody>
		<tr>
			<td>839 E Monark cycle ergometer&#160;</td>
			<td>Monark Exercise AB</td>
			<td>839 E</td>
			<td></td>
		</tr>
		<tr>
			<td>Heart rate monitor</td>
			<td>Polar</td>
			<td>Polar H1</td>
			<td></td>
		</tr>
		<tr>
			<td>Laptop</td>
			<td>Dell Inspiron</td>
			<td>varies</td>
			<td>any laptop computer with USB slots should work.</td>
		</tr>
		<tr>
			<td>EMG amplifiers</td>
			<td>BioPac Systems, Inc.</td>
			<td>100B</td>
			<td>100C are the latest version</td>
		</tr>
		<tr>
			<td>Disposable EMG electrodes</td>
			<td>BioPac Systems, Inc.</td>
			<td>EL-500</td>
			<td></td>
		</tr>
		<tr>
			<td>Sandpaper</td>
			<td>Home Depot</td>
			<td>9 in. x 11 in. 60 Grit course no-slip grip Advanced Sandpaper (3-Pack)</td>
			<td></td>
		</tr>
	</tbody>
</table>

determining the electromyographic fatigue threshold following a single visit exercise test

Teoricamente, o eletromiográficas (EMG) limiar de fadiga é a intensidade do exercício um indivíduo pode manter indefinidamente sem a necessidade de recrutar mais unidades motoras que está associada com um aumento na amplitude EMG. Embora os protocolos diferentes foram utilizadas para estimar o limite de fadiga EMG eles requerem visitas múltiplas que são impraticáveis ​​para um ambiente clínico. Aqui, apresentamos um protocolo para estimar o limiar de fadiga EMG para bicicleta ergométrica que exige uma única visita. Este protocolo é simples, conveniente e concluída dentro de 15-20 minutos, portanto, tem o potencial de ser traduzido em uma ferramenta que os clínicos podem usar em prescrição do exercício.

Como mostrado na Figura 1, para um único participante, cada saída de potência que é completada tem seis pontos de dados que representam a amplitude EMG do músculo vastus lateralis. Portanto, neste exemplo, a maior potência de saída com um não significativa (p&gt; 0,05) encosta-se a 200 watts, ao passo que a saída de potência mais baixa com um aumento significativo (p &lt;0,05) é de 225 W. inclinação Portanto, para este participante EMG limiar de fadiga é 213 W. Uma vez qu...

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Determining The Electromyographic Fatigue Threshold Following a Single Visit Exercise Test

This protocol describes the electromyographic fatigue threshold which demarcates between nonfatiguing and fatiguing exercise workloads. This information could be used to develop a more individualized training program.

Determinar o limiar de fadiga eletromiográfica Após um teste de esforço única visita

Theoretically, the electromyographic (EMG) fatigue threshold is the exercise intensity an individual can maintain indefinitely without the need to recruit ...

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12.5K visualizações.  Wayne State University. This protocol describes the electromyographic fatigue threshold which demarcates between nonfatiguing and fatiguing exercise workloads. This information could be used to develop a more individualized training program.

Vídeo: Determining The Electromyographic Fatigue Threshold Following a Single Visit Exercise Test

Making Sense of Listening: The IMAP Test Battery

The ability to hear is only the first step towards making sense of the range of information contained in an auditory signal. Of equal importance are the abilities to extract and use the information encoded in the auditory signal. We refer to these as listening skills (or auditory processing AP). Deficits in these skills are associated with delayed language and literacy development, though the nature of the relevant deficits and their causal connection with these delays is hotly debated.
When a child is referred to a health professional with normal hearing and unexplained difficulties in listening, or associated delays in language or literacy development, they should ideally be assessed with a combination of psychoacoustic (AP) tests, suitable for children and for use in a clinic, together with cognitive tests to measure attention, working memory, IQ, and language skills. Such a detailed examination needs to be relatively short and within the technical capability of any suitably qualified professional. Current tests for the presence of AP deficits tend to be poorly constructed and inadequately validated within the normal population. They have little or no reference to the presenting symptoms of the child, and typically include a linguistic component. Poor performance may thus reflect problems with language rather than with AP. To assist in the assessment of children with listening difficulties, pediatric audiologists need a single, standardized child-appropriate test battery based on the use of language-free stimuli.
We present the IMAP test battery which was developed at the MRC Institute of Hearing Research to supplement tests currently used to investigate cases of suspected AP deficits. IMAP assesses a range of relevant auditory and cognitive skills and takes about one hour to complete. It has been standardized in 1500 normally-hearing children from across the UK, aged 6-11 years. Since its development, it has been successfully used in a number of large scale studies both in the UK and the USA. IMAP provides measures for separating out sensory from cognitive contributions to hearing. It further limits confounds due to procedural effects by presenting tests in a child-friendly game-format. Stimulus-generation, management of test protocols and control of test presentation is mediated by the IHR-STAR software platform. This provides a standardized methodology for a range of applications and ensures replicable procedures across testers. IHR-STAR provides a flexible, user-programmable environment that currently has additional applications for hearing screening, mapping cochlear implant electrodes, and academic research or teaching.

A test battery (IMAP) for performing an in-depth assessment of auditory and cognitive abilities contributing to listening skills is described. It is quick to administer, child-friendly and free from linguistic confounds. Stimulus generation and protocol management are controlled via a software platform (IHR-STAR) to ensure replicable procedures.

Making Sense of Listening: A bateria de testes IMAP

The ability to hear is only the first step towards making sense of the range of information contained in an auditory signal. Of equal importance are the ...

Medicina

The Trier Social Stress Test Protocol for Inducing Psychological Stress

This article demonstrates a psychological stress protocol for use in a laboratory setting. Protocols that allow researchers to study the biological pathways of the stress response in health and disease are fundamental to the progress of research in stress and anxiety.1 Although numerous protocols exist for inducing stress response in the laboratory, many neglect to provide a naturalistic context or to incorporate aspects of social and psychological stress. Of psychological stress protocols, meta-analysis suggests that the Trier Social Stress Test (TSST) is the most useful and appropriate standardized protocol for studies of stress hormone reactivity.2 In the original description of the TSST, researchers sought to design and evaluate a procedure capable of inducing a reliable stress response in the majority of healthy volunteers.3 These researchers found elevations in heart rate, blood pressure and several endocrine stress markers in response to the TSST (a psychological stressor) compared to a saline injection (a physical stressor).3 Although the TSST has been modified to meet the needs of various research groups, it generally consists of a waiting period upon arrival, anticipatory speech preparation, speech performance, and verbal arithmetic performance periods, followed by one or more recovery periods. The TSST requires participants to prepare and deliver a speech, and verbally respond to a challenging arithmetic problem in the presence of a socially evaluative audience.3 Social evaluation and uncontrollability have been identified as key components of stress induction by the TSST.4 In use for over a decade, the goal of the TSST is to systematically induce a stress response in order to measure differences in reactivity, anxiety and activation of the hypothalamic-pituitary-adrenal (HPA) or sympathetic-adrenal-medullary (SAM) axis during the task.1 Researchers generally assess changes in self-reported anxiety, physiological measures (e.g. heart rate), and/or neuroendocrine indices (e.g. the stress hormone cortisol) in response to the TSST. Many investigators have adopted salivary sampling for stress markers such as cortisol and alpha-amylase (a marker of autonomic nervous system activation) as an alternative to blood sampling to reduce the confounding stress of blood-collection techniques. In addition to changes experienced by an individual completing the TSST, researchers can compare changes between different treatment groups (e.g. clinical versus healthy control samples) or the effectiveness of stress-reducing interventions.1

This article describes a protocol for inducing psychological stress in participants, which enables researchers to measure psychological, physiological and neuroendocrine responses to stress within single participants or between groups.

O Trier Protocolo de teste de estresse social para induzir Estresse Psicológico

This article demonstrates a psychological stress protocol for use in a laboratory setting.  Protocols that allow researchers to study the biological ...

Computerized Dynamic Posturography for Postural Control Assessment in Patients with Intermittent Claudication

Computerized dynamic posturography with the EquiTest is an objective technique for measuring postural strategies under challenging static and dynamic conditions. As part of a diagnostic assessment, the early detection of postural deficits is important so that appropriate and targeted interventions can be prescribed. The Sensory Organization Test (SOT) on the EquiTest determines an individual&#39;s use of the sensory systems (somatosensory, visual, and vestibular) that are responsible for postural control. Somatosensory and visual input are altered by the calibrated sway-referenced support surface and visual surround, which move in the anterior-posterior direction in response to the individual&#39;s postural sway. This creates a conflicting sensory experience. The Motor Control Test (MCT) challenges postural control by creating unexpected postural disturbances in the form of backwards and forwards translations. The translations are graded in magnitude and the time to recover from the perturbation is computed.
Intermittent claudication, the most common symptom of peripheral arterial disease, is characterized by a cramping pain in the lower limbs and caused by muscle ischemia secondary to reduced blood flow to working muscles during physical exertion. Claudicants often display poor balance, making them susceptible to falls and activity avoidance. The Ankle Brachial Pressure Index (ABPI) is a noninvasive method for indicating the presence of peripheral arterial disease and intermittent claudication, a common symptom in the lower extremities. ABPI is measured as the highest systolic pressure from either the dorsalis pedis or posterior tibial artery divided by the highest brachial artery systolic pressure from either arm. This paper will focus on the use of computerized dynamic posturography in the assessment of balance in claudicants.

Individuals with intermittent claudication exhibit poor balance compared to healthy controls. Computerized dynamic posturography is an objective method for measuring an individual's postural responses to balance disturbances. This provides an objective reflection of the person&#x2019;s ability to respond to situations under which sensory stimuli are altered and unexpected perturbations occur.

Posturografia Dinâmica Computadorizada para Avaliação do controle postural em pacientes com claudicação intermitente

Computerized dynamic posturography with the EquiTest is an objective technique for measuring postural strategies under challenging static and dynamic ...

A Methodological Approach to Non-invasive Assessments of Vascular Function and Morphology

The endothelium is the innermost lining of the vasculature and is involved in the maintenance of vascular homeostasis. Damage to the endothelium may predispose the vessel to atherosclerosis and increase the risk for cardiovascular disease. Assessments of peripheral endothelial function are good indicators of early abnormalities in the vascular wall and correlate well with assessments of coronary endothelial function. The present manuscript details the important methodological steps necessary for the assessment of microvascular endothelial function using laser Doppler imaging with iontophoresis, large vessel endothelial function using flow-mediated dilatation, and carotid atherosclerosis using carotid artery ultrasound. A discussion on the methodological considerations for each of the techniques is also presented, and recommendations are made for future research.

The present article describes the methodological considerations for several non-invasive assessments of vascular function and morphology that are commonly used in medical research to assess different stages of atherosclerosis.

Uma abordagem metodológica para avaliações não-invasivas de função vascular e Morfologia

The endothelium is the innermost lining of the vasculature and is involved in the maintenance of vascular homeostasis.  Damage to the endothelium may ...

Ultrasound Assessment of Endothelial Function: A Technical Guideline of the Flow-mediated Dilation Test

Cardiovascular disease is the primary cause of mortality and a major cause of disability worldwide. The dysfunction of the vascular endothelium is a pathological condition characterized mainly by a disruption in the balance between vasodilator and vasoconstrictor substances and is proposed to play an important role in the development of atherosclerotic cardiovascular disease. Therefore, a precise evaluation of endothelial function in humans represents an important tool that could help better understand the etiology of multiple cardio-centric pathologies.
Over the past twenty-five years, many methodological approaches have been developed to provide an assessment of endothelial function in humans. Introduced in 1989, the FMD test incorporates a forearm occlusion and subsequent reactive hyperemia that promotes nitric oxide production and vasodilation of the brachial artery. The FMD test is now the most widely utilized, non-invasive, ultrasonic assessment of endothelial function in humans and has been associated with future cardiovascular events.
Although the FMD test could have clinical utility, it is a physiological assessment that has inherited several confounding factors that need to be considered. This article describes a standardized protocol for determining FMD including the recommended methodology to help minimize the physiological and technical issues and improve the precision and reproducibility of the assessment.

The flow mediated dilation (FMD) test is the most commonly utilized, non-invasive, ultrasound assessment of endothelial function in humans. Although the FMD test has been related with the prediction of future cardiovascular disease and events, it is a physiological assessment with many inherent confounding factors that need to be considered.

Avaliação ultra-sons da função endotelial: A Orientação Técnica do Teste de dilatação fluxo-mediada

Cardiovascular disease is the primary cause of mortality and a major cause of disability worldwide. The dysfunction of the vascular endothelium is a ...

Experimental Protocol of a Three-minute, All-out Arm Crank Exercise Test in Spinal-cord Injured and Able-bodied Individuals

Reliable exercise protocols are required to test changes in exercise performance in elite athletes. Performance improvements in these athletes may be small; therefore, sensitive tools are fundamental to exercise physiology. There are currently many exercise tests that allow for the examination of exercise capacity in able-bodied athletes, with protocols mainly for lower-body or whole-body exercise. There is a trend to test athletes in a sport-specific setting that closely resembles the actions that the participants are used to performing. Only a few protocols test short-term, high-intensity exercise capacity in participants with an impairment of the lower body. Most of these protocols are very sport-specific and are not applicable to a wide range of athletes. One well-known test protocol is the 30 s Wingate test, which is well-established in cycling and in arm crank exercise testing. This test analyzes high-intensity exercise performance over a 30 s time duration. In order to monitor exercise performance over a longer duration, a different method was modified for application to the upper body. The 3 min, all-out arm crank ergometer test allows athletes to be tested in a manner specific to 1,500 m wheelchair racing (in terms of exercise duration), as well as to upper body exercises such as rowing or hand-cycling. In order to increase the reliability with identical test conditions, it is crucial to precisely replicate settings such as the resistance (i.e., torque factor) and the position of the participants (i.e., the height of the crank, the distance between the crank and the participant, and the fixation of the participant). Another important issue concerns the beginning of the exercise test. Fixed revolutions per minute are required to standardize the test conditions for the start of the exercise test. This exercise protocol shows the importance of accurate operations to reproduce identical test conditions and settings.

We present a protocol to test the aerobic and anaerobic power of the upper body muscles over a duration of 3 min in able-bodied as well as in paraplegic and tetraplegic individuals. The protocol presents specific modifications in its application for upper-body exercise in individuals with or without disability.

Protocolo Experimental de um Teste de Exercício de Manivela de Braga de 3 minutos, em todos os casos, em indivíduos com feridas e indivíduos não capacitados.

Reliable exercise protocols are required to test changes in exercise performance in elite athletes. Performance improvements in these athletes may be ...

Taste Exam: A Brief and Validated Test

The emerging importance of taste in medicine and biomedical research, and new knowledge about its genetic underpinnings, has motivated us to supplement classic taste-testing methods in two ways. First, we explain how to do a brief assessment of the mouth, including the tongue, to ensure that taste papillae are present and to note evidence of relevant disease. Second, we draw on genetics to validate taste test data by comparing reports of perceived bitterness intensity and inborn receptor genotypes. Discordance between objective measures of genotype and subjective reports of taste experience can identify data collection errors, distracted subjects or those who have not understood or followed instructions. Our expectation is that fast and valid taste tests may persuade researchers and clinicians to assess taste regularly, making taste testing as common as testing for hearing and vision. Finally, because many tissues of the body express taste receptors, taste responses may provide a proxy for tissue sensitivity elsewhere in the body and, thereby, serve as a rapid, point-of-care test to guide diagnosis and a research tool to evaluate taste receptor protein function.

This protocol measures human taste responses and includes a brief anatomical assessment, a short taste test, and a validation method using the subject&#39;s reported sensation and taste receptor genotype.

: Sabor um breve e validado teste exame

The emerging importance of taste in medicine and biomedical research, and new knowledge about its genetic underpinnings, has motivated us to supplement ...

'Boden Food Plate': Novel Interactive Web-based Method for the Assessment of Dietary Intake

Different methods can be used in research to assess dietary intake, many of which are still paper-based. Written estimated food diaries are often utilized in clinical trials, despite being a burden for both study participants and researchers. This method requires participant literacy, it is time consuming, labor intensive, and can easily lead to under-reporting. With advancements in technology, there is a growing interest in electronic diaries that automate the dietary assessment process. These are focused on improving accuracy, reducing both time and cost and providing users with a visual and more enjoyable experience. The methodology presented here aimed to validate the &#39;Boden Food Plate&#39;, a novel web-based platform for self-recording of food and drink items, compared to a traditional estimated food diary. The application was also rated on a satisfaction scale by study participants using a paper-based questionnaire. Sixty-seven participants completed the dietary measures on both the three-day electronic and paper food diaries. For the analysis, only dietary data completed at both study time points (baseline and week six) was utilized. Despite small mean differences between dietary data collection methods, Bland Altman analysis showed fairly wide 95% limits of agreement between the electronic platform and the written estimated food diary and there were few cases which did not fall within the 95% confidence intervals. Overall, participants found the electronic food diary to be more fun than the paper method and as easy to use as hard copy diaries. The new platform has potential as a self-recording tool for the collection of dietary data, particularly when utilized in clinical trial settings. However, further validation studies are needed to improve the validity of this novel electronic dietary data collection tool.

&#039;Boden Food Plate&#039;: Novel Interactive Web-based Method for the Assessment of Dietary Intake

The &#39;Boden Food Plate&#39; is an electronic food diary designed to be an interactive and fun method to collect dietary intake using visual depictions. The purpose of this study was to validate the web-based application against a traditional three-day estimated food diary method.

«Placa de Boden Food»: novo método interativo baseado na Web para a avaliação da ingestão alimentar

Different methods can be used in research to assess dietary intake, many of which are still paper-based. Written estimated food diaries are often utilized ...

Conducting Maximal and Submaximal Endurance Exercise Testing to Measure Physiological and Biological Responses to Acute Exercise in Humans

Regular physical activity has a positive effect on human health, but the mechanisms controlling these effects remain unclear. The physiologic and biologic responses to acute exercise are predominantly influenced by the duration and intensity of the exercise regimen. As exercise is increasingly thought of as a therapeutic treatment and/or diagnostic tool, it is important that standardizable methodologies be utilized to understand the variability and to increase the reproducibility of exercise outputs and measurements of responses to such regimens. To that end, we describe two different cycling exercise regimens that yield different physiologic outputs. In a maximal exercise test, exercise intensity is continually increased with a greater workload resulting in an increasing cardiopulmonary and metabolic response (heart rate, stroke volume, ventilation, oxygen consumption and carbon dioxide production). In contrast, during endurance exercise tests, the demand is increased from that at rest, but is raised to a fixed submaximal exercise intensity resulting in a cardiopulmonary and metabolic response that typically plateaus. Along with the protocols, we provide suggestions on measuring physiologic outputs that include, but are not limited to, heart rate, slow and forced vital capacity, gas exchange metrics, and blood pressure to enable the comparison of exercise outputs between studies. Biospecimens can then be sampled to assess cellular, protein, and/or gene expression responses. Overall, this approach can be easily adapted into both short- and long-term effects of two distinct exercise regimens.

To assess the influence of exercise intensity on physiologic and biologic responses, two different exercise testing protocols were utilized. Methods outlining exercise testing on a cycle ergometer as an incremental maximal oxygen consumption test and endurance, steady state submaximal endurance test are described.

Realização de exercícios de resistência máxima e submáxima testes para medir as respostas fisiológicas e biológicas ao exercício agudo em humanos

Regular physical activity has a positive effect on human health, but the mechanisms controlling these effects remain unclear. The physiologic and biologic ...

Setup and Execution Of the Blindfolded Code Training Exercise

Miscommunication is the most common cause of preventable patient harm in medicine. Currently, there is limited knowledge of innovative techniques to improve resident physician communication and leadership strategies in high-acuity situations. The blindfolded code training exercise removes visual stimuli from the team leader, forcing the team leader to effectively utilize closed-loop communication. The simple act of blindfolding the team leader creates a learning environment where the leader must utilize a conceptual framework and critical thinking strategies to organize the team and manage the resuscitation. An advantage to this teaching technique is that it does not require any special simulation equipment, making it a low-cost approach. The blindfolded code training exercise can be applied to the management of any critically ill patient where the primary objective is to focus on developing communication skills in acute resuscitations. The purpose of the description of the blindfolded code training exercise is to provide guidance on how to perform this innovative teaching technique to force effective closed-loop communication.

The blindfolded code training exercise, which blindfolds the team leader in a code resuscitation simulation, is an advanced teaching technique to improve closed-loop communication, organizational skills, and critical thinking.&#160;

Instalação e execução do exercício de treino código com os olhos vendados

Miscommunication is the most common cause of preventable patient harm in medicine. Currently, there is limited knowledge of innovative techniques to ...