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

Todos los procedimientos fueron aprobados por la Junta de Revisión Institucional de la Universidad de Sujetos Humanos. 1. Preparación de la pierna del Participante <ol><li> Haga que el participante cuidadosamente enrollar sus pantalones cortos para el tramo deseado. Luego pegue los cortos para que los cuádriceps femoral grupo muscular está expuesto y trace una línea alrededor de la zona del participante necesita afeitarse. </li><li> IMPORTANTE: Haga que el participante se afeita su pierna antes de la prueba más que el día anterior, ya que asegura que no hay rastrojos que pueden interferir con la señal EMG. </li><li> Una vez que el participante haya terminado de afeitarse la zona deseada de la pierna, limpie la zona afeitada con alcohol para asegurar que no hay restos del gel de afeitar (o crema), que puede interferir con la señal EMG. </li></ol> 2. Medición de la pierna por la colocación de electrodos <ol><li> Para colocar el electrodo EMG en el músculo vasto lateral, hacer el fomediciones llowing <ol><li> Haga que el participante de pie frente recta el investigador. </li><li> Busque el bífida anterior iliaca Superior (ASIS) y el lado lateral de la rótula. El ASIS es el hueso de la cadera; palpar mediante la colocación de la mano en cada lado del abdomen por debajo del ombligo. </li><li> Con una cinta métrica, medir la distancia entre los dos lugares identificados anteriormente y tomar 2/3 de ese valor en la línea de la ASIS en el lado lateral de la rótula. Nota: Para más información sobre la colocación de electrodos EMG se puede encontrar en la SENIAM (electromiografía de superficie para la evaluación no invasiva de los músculos) URL: http://www.seniam.org/ </li></ol></li></ol> 3. La colocación de los electrodos EMG <ol><li> Después se ha identificado la ubicación del vasto lateral, tome los electrodos EMG (la mayoría de los investigadores utilizan comercialmente disponibles desechables electrodos Ag Ag-Cl) y el lugar más vasto lateral sin quitar el adhesivo shield. Luego, con una pluma marcar el área donde la porción de gel del electrodo hace contacto con el músculo. Asegúrese de que la distancia entre los electrodos es de 20 mm de centro a centro. </li><li> Utilice un trozo de papel de lija (60 grueso) para raspar suavemente estas dos áreas para eliminar la capa superficial de la piel. Durante este tiempo, pida al participante su nivel de incomodidad. Deje de abrasión cuando el participante indica el área es cálido. </li><li> Limpie las áreas erosionadas con una toalla humedecido con alcohol o un algodón con alcohol. Deje que la zona en la pierna que se seque antes de colocar los electrodos EMG. </li><li> Coloque los electrodos EMG en los sitios que fueron pulidas (Figura 2). Tenga cuidado de no colocar los electrodos en la banda iliotibial (banda de TI). Pídale al participante que contraer los músculos del cuadriceps femoral con el fin de palpar el vasto lateral. Coloque los electrodos en el músculo para asegurarse de que no está en la banda de TI. Nota: Si los electrodos en la banda de TI, la señal de que está EMGld ser humedecido cuando se le pide al participante que máximamente contrato. </li><li> Coloque el electrodo de referencia (3 rd electrodo) en un sitio de unión huesudo como el ASIS tanto no interfieran con el movimiento de las extremidades inferiores durante la sesión de ejercicio. </li></ol> 4. Comprobación de la señal EMG <ol><li> Antes de iniciar la prueba de esfuerzo, compruebe la impedancia entre los electrodos. Nota: Este paso es fundamental porque si la señal tiene demasiado ruido, entonces los datos EMG recogidos durante la prueba de esfuerzo no serán válidos. <ol><li> Haga que el participante se sienta en una silla y conecte el EMG lleva a sus respectivos electrodos colocados en la pierna del participante. </li><li> En este punto, tiene el participante relajar su pierna, al no tener la tensión en el músculo. Luego, después de unos 30 segundos de relajación, tiene el participante al máximo contraiga sus músculos cuádriceps femoral durante 5 segundos y luego volver a ser completamente relajado. </li><li> Al realizar la tarea de unBove (paso 4.1.2), grabar la señal de EMG participantes en el equipo. </li><li> Asegúrese de que la impedancia entre los electrodos es &lt;2.000 ohmios. Por otra parte, si un voltímetro está disponible en el laboratorio, a continuación, comprobar el ruido de línea de base y mantener por debajo de 5 mV. Además, establecer la frecuencia de muestreo a 1.000 Hz. </li></ol></li></ol> 5. Configurando el cicloergómetro <ol><li> Después de comprobar la impedancia entre los electrodos, que el movimiento de los participantes de la silla a la bicicleta ergométrica. </li><li> Haga que el participante de pie junto a la bicicleta ergométrica y elevar la rodilla hasta que el muslo quede paralelo al suelo. Luego haga que el participante mantenga esta posición y ajustar la altura del asiento para que coincida con la misma altura que el muslo de la participante. </li><li> A partir de entonces, tiene el participante se sienta en el asiento del cicloergómetro y luego pedalear un par de veces mientras preguntándoles si se sienten cómodos con la altura del asiento. Si es necesario, ajustar la altura del asiento. </li><li> Asegurar that piernas de los participantes son la extensión completa próximo con una ligera flexión (~ 5 °) en las rodillas durante cada revolución del pedal. </li><li> Antes de comenzar la prueba, tiene el participante use un monitor de ritmo cardíaco polar para que la frecuencia cardíaca se puede documentar toda la prueba de esfuerzo. </li></ol> 6. Realizar el Protocolo Umbral EMG Fatiga <ol><li> Haga que el participante inicia el ciclismo y poco a poco aumentar su cadencia de 70 revoluciones / min. A continuación, aumentar la potencia de salida en el cicloergómetro a 50 W. </li><li> Tener el ciclo participante en esta salida de potencia durante aproximadamente 2-3 minutos. Nota: Este es un ejercicio de baja intensidad y servirá de calentamiento. </li><li> Después del período de calentamiento, aumentar la potencia de salida de 25 W cada 2 min hasta que el participante ya no es capaz de mantener el 70 revoluciones / min cadencia o pide que se detuvo la prueba. Nota: Cabe señalar que durante la prueba de ejercicio, la señal de EMG se registra para 10épocas seg durante cada etapa de 2 min para seg 10-20, 30-40, 50-60, 70-80, 90-100 y 110-120 21. La mayoría de los sistemas EMG tendrán una opción para configurar la grabación automática en el intervalo deseado. Por lo tanto, para cada etapa no debería ser 6 archivos de datos. </li><li> Una vez que el test incremental ha llegado a la conclusión, que el participante realice un enfriamiento a 50 W. Compruebe que la longitud del enfriamiento corresponde con tener la frecuencia cardíaca regreso del participante en el valor durante la fase de calentamiento. Monitorear esto comprobando la frecuencia cardíaca de los participantes mediante el monitor de ritmo cardíaco polar. </li><li> Una vez completado el enfriamiento, retirar el EMG conduce y tiene el participante baje del cicloergómetro y volver a la silla. A continuación, retire con cuidado los electrodos EMG y limpie las áreas con una toalla limpia humedecida con alcohol o un algodón con alcohol. </li></ol> 7. El procesamiento de la señal EMG <ol><li> Después de que se complete la prueba, proCESS los archivos RAW de datos EMG que se recogieron durante la prueba de ejercicio para que los datos pueden ser utilizados para determinar el umbral de fatiga EMG. <ol><li> Realizar el procesamiento de la señal EMG, ya sea con el software utilizado para recoger la señal de EMG o software escrito personalizado utilizando diversas plataformas como MATLAB o LabVIEW. </li><li> Filtra las señales EMG recogidas utilizando un filtro de paso de banda. Utilice un ajuste de 10 a 500 Hz. Nota: Esto altera la frecuencia de la señal de modo que los artefactos de baja frecuencia debido al movimiento de los cables EMG (&lt;10 Hz), y artefactos de alta frecuencia desde el medio ambiente (&gt; 500 Hz), se eliminan. Use un filtro de corte de 60 Hz si hay alguna interferencia de la fuente de alimentación del ordenador o sistema de EMG. </li><li> Una vez que la señal ha sido filtrada, determinar la amplitud de la señal mediante el cálculo del valor cuadrático medio de la señal: la plaza cada uno de los puntos de datos, resumir ellos, se divide por el número de puntos de datos, luego tomar la raíz cuadrada del valor resultante. Lleve a cabo estos cálculos utilizando el software mencionado. </li></ol></li></ol> 8. Determinación del Umbral EMG Fatiga para cada participante <ol><li> Realice los siguientes pasos para cada participante. <ol><li> Después de la señal EMG ha sido procesado; utilizar un programa estadístico (por ejemplo: GraphPad Prism) y la etiqueta de la primera columna &quot;Tiempo&quot; y las columnas posteriores con las salidas de potencia utilizados para la prueba. </li><li> Para cada salida de potencia, rellenar el valor correspondiente amplitud EMG para cada intervalo de 20 seg. </li><li> Para cada salida de potencia, analizar el tiempo (eje x) vs EMG amplitud (eje y) con relación de regresión lineal para determinar si la pendiente de la línea de regresión es significativa (p &lt;0,05) diferente de cero. </li><li> Después de realizar el análisis de regresión lineal para todas las salidas de potencia, identificar la potencia de salida más alta con una no significativa (p&gt; 0,05) pendiente. </li><li> Luego identificar el lpotencia owest con una pendiente significativa (p &lt;0,05). </li><li> Una vez que estas dos potencias han sido identificados, añadirlos y dividir por 2; la potencia de salida resultante es el umbral de fatiga estimada EMG. </li></ol></li></ol>

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The authors have nothing to disclose.

Estamos aquí presentamos un método para determinar la fatiga neuromuscular en el cuádriceps femoral músculos para el ejercicio dinámico. Este método proporciona un enfoque sencillo y no invasivo para el uso de EMG superficial. Por otra parte, la versatilidad de este método es que los investigadores puedan adaptarlo a otros modos de ejercicio, como la cinta de correr 20. Teóricamente, para intensidades en o por debajo del umbral de fatiga EMG el participante debe ser capaz ...

Electromiografía de superficie (EMG) es un enfoque no invasivo de estudio reclutamiento de unidades motoras durante isométrica 1-3, isocinético 4-6, 7-10 o acción muscular continua. La amplitud de la señal de EMG representa la activación muscular que consiste en el número de unidades motoras activado, la tasa de disparo de las unidades de motor, o ambos 11. El concepto de umbral de la fatiga EMG se utiliza para indicar la más alta carga de trabajo en la que un individuo puede ejercer indefinidamente sin un aumento en la amplitud EMG 8. Es importante discusión brevemente el origen del umbral de fatiga EMG. El estudio original de deVries et al. 12 implicó un protocolo que consistió en múltiples (generalmente 3-4) series de trabajo discontinuos, donde la amplitud EMG se representa en función del tiempo para cada pelea trabajo. A continuación, la potencia de salida se representó frente a los coeficientes de pendiente de la amplitud EMG frente rela tiempo<html> rela-, y luego extrapolada a cero pendiente (la intersección) 12. Los autores 12 denominaron originalmente que el protocolo de la capacidad de trabajo físico en el umbral de fatiga (PWCFT). En otro estudio, deVries et al. 13 utilizaron series de trabajo discontinuos, pero utilizó regresión lineal para encontrar la primera potencia que resultó en una pendiente significativa para la amplitud EMG frente relación de tiempo. Los autores 13 también denominados ese protocolo del PWCFT, creando cierta confusión en la literatura. En un artículo posterior, deVries et al. 14 modificó su protocolo anterior 13 y se desarrolló un protocolo de incremento continuo. La amplitud EMG se representó gráficamente contra el tiempo para cada salida de potencia y la PWCFT se definió como el promedio de la potencia de salida más alto que resultó en ningún cambio en la amplitud EMG con el tiempo y la potencia de salida más bajo que resultó en un aumento de la amplitud en el tiempo EMG 14 . ent &quot;&gt; Cabe señalar que el término PWC fue introducido originalmente a finales de 1950 15,16 y es sinónimo de una gran cantidad de literatura (pasado, presente, y en diferentes países) el examen de la capacidad aeróbica a una determinada carga de trabajo 17. Por otra parte, el término se utiliza en la literatura ergonómico e industrial que se centran en la productividad del día a día de los trabajadores que realizan la acción repetitiva durante el día de trabajo 8 horas como individuos en una planta de montaje 18. El umbral de fatiga EMG término fue utilizado inicialmente por Matsumoto et al 19 después de que se modificaron el 12 deVries protocolo donde la salida de potencia en comparación con coeficientes de pendiente de la amplitud EMG frente relación de tiempo se representan y se extrapoló hasta el punto de pendiente cero. Más recientemente, Guffey et al. 20 y Briscoe et al. 8 utiliza el método de deVries et al. 14 y la terminología de Matsumoto et una. l 19 para definir operacionalmente el umbral de fatiga EMG. En el futuro, se recomienda que se utilice el umbral EMG fatiga plazo. Por lo tanto, la amplitud EMG frente a la relación tiempo se traza para cada salida de potencia y después se analizó mediante análisis de regresión lineal (Figura 1). Para estimar el umbral de fatiga EMG, la potencia de salida más alta con una (p&gt; 0,05) la pendiente no significativa y la salida de energía más bajo, con una disminución significativa (p &lt;0,05) la pendiente se identifica y luego el promedio se calcula 14. Este protocolo es simple, conveniente y completado dentro de 15 a 20 min. Por otra parte, la tasa de incremento puede ser modulada en función del nivel del individuo de la actividad física habitual, y por lo tanto tiene aplicaciones potenciales en el ámbito clínico.

<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

Teóricamente, el (EMG) umbral de fatiga electromiográfica es la intensidad del ejercicio que un individuo puede mantener indefinidamente sin la necesidad de reclutar más unidades motoras que se asocia con un aumento en la amplitud EMG. Aunque protocolos diferentes se han utilizado para estimar el umbral de fatiga EMG que requieren múltiples visitas que son poco práctico para un entorno clínico. A continuación, presentamos un protocolo para la estimación del umbral de fatiga EMG para cicloergometría que requiere una sola visita. Este protocolo es simple, conveniente y completado dentro de 15 a 20 minutos, por lo tanto, tiene el potencial de traducirse en una herramienta que los médicos pueden usar en la prescripción del ejercicio.

Como se muestra en la Figura 1, para un único participante, cada salida de potencia que se completa tiene seis puntos de datos que representan la amplitud EMG para el músculo vasto lateral. Por lo tanto, en este ejemplo, la salida de potencia más alta con una no significativa (p&gt; 0,05) pendiente es 200 vatios, mientras que la salida de potencia más bajo con una disminución significativa (p &lt;0,05) pendiente es 225 W. Por lo tanto, para este participante la EMG umbral de la fa...

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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 el umbral de fatiga electromiográfica Tras una prueba de esfuerzo individual Visita

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

determining-electromyographic-fatigue-threshold-following-single

Research

JoVE Journal

Medicine

12.4K vistas.  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.

Video: 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.

Tener sentido de la escucha: la batería de pruebas 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 ...

Investigación

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.

El estrés social Trier Protocolo de prueba para la inducción de estrés 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.

Posturografía dinámica computarizada para la evaluación de control postural en pacientes con claudicación intermitente

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

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.

La evaluación ecográfica de la función endotelial: Una guía técnica de la prueba de dilatación mediada por flujo

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 una prueba de esfuerzo de manivela de tres minutos y de brazo completo en individuos con lesión o con cuerpos espinales

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

A Technique for Subcutaneous Abdominal Adipose Tissue Biopsy via a Non-diathermy Method

Adipose tissue biopsies offer tissue samples that, upon analysis, may provide insightful overviews of mechanisms relating to metabolism and disease. To obtain subcutaneous adipose tissue biopsies in the abdominal area, researchers and physicians use either a surgical or a needle-based technique. However, surgical subcutaneous fat biopsies can offer tissue samples that may provide a more comprehensive overview of the complexities of biological indices in white adipose tissue. Usually, a surgical adipose tissue biopsy includes a diathermy treatment for cauterizing blood vessels to prevent excessive bleeding. Nevertheless, side effects, such as flash fires and skin lesions in the tissue, have been reported after diathermy. Therefore, we aimed to standardize a surgical abdominal adipose tissue biopsy performed under local anesthesia using a non-diathermy method. We conducted 115 subcutaneous adipose tissue biopsies in healthy men using a non-diathermy abdominal surgical biopsy method. Our results showed three cases of excessive post-operation bleeding out of 115 operations (2.61%).In conclusion, our standardized subcutaneous abdominal adipose tissue surgical biopsy using a non-diathermy method can be safely applied to healthy men at the bedside, with minimal side effects.

We standardized an abdominal adipose tissue biopsy using a non-diathermy method performed under local anesthesia. Three cases of excessive post-operation bleeding out of 115 operations (2.61%) occurred.We conclude that an abdominal adipose tissue surgical biopsy using a non-diathermy method can be safely applied to healthy men.

Una técnica para biopsia de tejido adiposo Abdominal subcutáneo mediante un método no-diatermia

Adipose tissue biopsies offer tissue samples that, upon analysis, may provide insightful overviews of mechanisms relating to metabolism and disease. To ...

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.

Examen de gusto: Una prueba breve y validada

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 del alimento de Boden': nuevo método interactivo basado en Web para la evaluación de ingesta dietética

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.

Realización de ejercicio máximo y submáximo resistencia pruebas para medir las respuestas fisiológicas y biológicas al ejercicio agudo en seres 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;

Configuración y ejecución del ejercicio de entrenamiento de código con los ojos vendados

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