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

Toutes les procédures ont été approuvées par l&#39;Institutional Review Board de l&#39;Université pour des sujets humains. 1. Préparation de la jambe du participant <ol><li> Vous avez parfaitement le participant retrousser leurs shorts pour la jambe souhaitée. Puis collez-le short de sorte que les quadriceps fémoral groupe musculaire est exposée et tracer une ligne autour de la zone le participant a besoin de se raser. </li><li> IMPORTANT: Vous avez le participant raser leur jambe avant le test plutôt que le jour précédent, ce qui assure qu&#39;il n&#39;y a pas chaumes qui peuvent interférer avec le signal EMG. </li><li> Une fois que le participant a terminé le rasage de la zone souhaitée de la jambe, nettoyer la zone rasée avec alcool à friction pour assurer qu&#39;il n&#39;y a pas de restes de gel de rasage (ou crème) qui peuvent interférer avec le signal EMG. </li></ol> 2. Mesure de la jambe pour le placement des électrodes <ol><li> Afin de placer l&#39;électrode EMG sur le muscle vaste externe, faire de la foLes mesures de llowing <ol><li> Demandez au participant de se tenir droit face le chercheur. </li><li> Localisez le spina antérieure iliaca supérieure (ASIS) et le côté latéral de la rotule. L&#39;ASIS est l&#39;os de la hanche; palper en plaçant la main de chaque côté de l&#39;abdomen dessous de l&#39;ombilic. </li><li> Avec un ruban à mesurer, mesurer la distance entre les deux endroits identifiés ci-dessus et de prendre 2/3 de cette valeur sur la ligne de l&#39;ASIS pour le côté latéral de la rotule. Remarque: Pour plus d&#39;informations concernant le placement des électrodes EMG peut être trouvé sur le SENIAM (en électromyographie de surface pour l&#39;évaluation non invasive des muscles) URL: http://www.seniam.org/ </li></ol></li></ol> 3. placement des électrodes EMG <ol><li> Après l&#39;emplacement du vaste externe a été identifié, prendre les électrodes EMG (la plupart des chercheurs utilisent des électrodes jetables disponibles dans le commerce Ag-Ag Cl) et le lieu plus vaste externe sans enlever le sh adhésifield. Ensuite, avec un stylo marquer la zone où la partie de gel de l&#39;électrode entre en contact avec le muscle. Assurez-vous que la distance inter-est de 20 mm de centre à centre. </li><li> Utilisez un morceau de papier de verre (60 grossière) pour roder doucement ces deux domaines pour enlever la couche superficielle de la peau. Pendant ce temps, demander au participant de leur niveau d&#39;inconfort. Arrêtez abrasion lorsque le participant indique la zone est chaude. </li><li> Nettoyez les zones abrasées avec une serviette qui est imbibé d&#39;alcool ou un tampon imbibé d&#39;alcool à friction. Laisser la région sur la jambe de sécher avant de placer les électrodes EMG. </li><li> Placer les électrodes EMG sur les sites qui ont été abrasée (figure 2). Prenez soin de ne pas placer les électrodes sur la bandelette de Maissiat (bande IT). Demandez au participant de contracter les muscles de quadriceps afin de palper le vaste externe. Placer les électrodes sur le muscle pour assurer qu&#39;il ne figure pas sur la bande de l&#39;information. Remarque: Si les électrodes sur la bande informatique, le signal EMG would être freinée lorsque le participant est invité à maximum contrat. </li><li> Placez l&#39;électrode de référence (3 e de l&#39;électrode) sur un site de fixation de Boney comme l&#39;ASIS donc pas interférer avec le mouvement des membres inférieurs au cours de la séance d&#39;exercice. </li></ol> 4. Vérification du signal EMG <ol><li> Avant de commencer le test d&#39;exercice, vérifiez l&#39;impédance inter. Remarque: Cette étape est essentielle car si le signal a trop de bruit, alors les données EMG réunies lors du test d&#39;exercice seront invalides. <ol><li> Demandez le participant assis dans un fauteuil et brancher le EMG conduit à leurs électrodes respectives attachées à la jambe du participant. </li><li> À ce stade, ont le participant se détendre leur jambe, ayant aucune tension dans le muscle. Puis, après environ 30 secondes de détente, ont le participant contracter au maximum leurs muscles quadriceps fémoral pendant 5 secondes, puis revenir à étant complètement détendu. </li><li> Lors de l&#39;exécution de la tâche d&#39;unBove (étape 4.1.2), enregistrer la participants de signal EMG sur l&#39;ordinateur. </li><li> Assurez-vous que l&#39;impédance inter est &lt;2.000 ohms. En outre, si un voltmètre est disponible dans le laboratoire, puis vérifier le bruit de fond et de garder en dessous de 5 mV. En outre, régler la fréquence d&#39;échantillonnage à 1000 Hz. </li></ol></li></ol> 5. Mise en place du cycle ergomètre <ol><li> Après avoir vérifié l&#39;impédance inter, avoir le déménagement des participants de la chaise à l&#39;ergomètre. </li><li> Demandez le participant debout à côté de l&#39;ergomètre et augmenter leur genou jusqu&#39;à la cuisse est parallèle au sol. Puis ont le participant maintenez cette position et d&#39;ajuster la hauteur du siège pour correspondre à la même hauteur que la cuisse du participant. </li><li> Par la suite, ont le participant assis sur le siège de bicyclette ergométrique puis pédaler à quelques reprises tout en leur demandant si elles sont à l&#39;aise avec la hauteur du siège. Si nécessaire, ajuster la hauteur du siège. </li><li> Assurez-that les jambes des participants sont l&#39;extension presque plein avec une légère courbure (~ 5 °) dans les genoux pendant chaque tour de pédale. </li><li> Avant de commencer le test, ont le participant de porter un moniteur de fréquence cardiaque Polar sorte que la fréquence cardiaque peut être documenté tout au long du test d&#39;effort. </li></ol> 6. Effectuer le Protocole de seuil EMG Fatigue <ol><li> Demandez le participant démarre le cyclisme et progressivement augmenter leur cadence à 70 tours / min. Puis augmenter la puissance de sortie sur la bicyclette ergométrique à 50 W. </li><li> Avoir le cycle de participant à ce puissance pendant environ 2-3 min. Note: Ceci est un exercice de faible intensité et servira le warm-up. </li><li> Après la période d&#39;échauffement, augmenter la puissance de sortie de 25 W toutes les 2 min jusqu&#39;à ce que le participant est plus en mesure de maintenir le 70 tours / min cadence ou demande que l&#39;interruption du test. Remarque: Il est à noter que lors de l&#39;essai de l&#39;exercice, le signal EMG est enregistrée pour 10époques sec pendant chaque étape de 2 min pour sec 10-20, 30-40, 50-60, 70-80, 90-100, 110-120 et 21. La plupart des systèmes EMG auront une option pour définir l&#39;enregistrement automatique à l&#39;intervalle souhaité. Ainsi, pour chaque phase il devrait y avoir six fichiers de données. </li><li> Une fois le test supplémentaire a conclu, avoir le participant effectuer un refroidissement à 50 W. Vérifiez que la longueur du refroidissement correspond avoir le retour de la fréquence cardiaque du participant à la valeur au cours de la phase d&#39;échauffement. Surveiller en vérifiant le rythme cardiaque du participant utilisant le cardiofréquencemètre polaire. </li><li> Une fois que le refroidissement est terminé, retirez la EMG et ont conduit le participant descendez l&#39;ergomètre de cycle et revenir à la chaise. Puis retirez délicatement les électrodes EMG et essuyez les zones avec une serviette propre humidifié avec de l&#39;alcool ou un tampon imbibé d&#39;alcool à friction. </li></ol> 7. Traitement du Signal EMG <ol><li> Après le test est terminé, proCESS les fichiers de données EMG premières qui ont été recueillies au cours de l&#39;épreuve d&#39;effort de sorte que les données peuvent être utilisées pour déterminer le seuil de fatigue EMG. <ol><li> Effectuer un traitement du signal EMG avec soit le logiciel utilisé pour recueillir le signal EMG ou un logiciel personnalisé écrit en utilisant différentes plates-formes telles que MATLAB ou LabVIEW. </li><li> Filtrer les signaux EMG recueillies en utilisant un filtre passe-bande. Utilisez un réglage de 10 à 500 Hz. Remarque: Cette modifie la fréquence du signal de sorte que les artefacts de fréquences basses dues au mouvement des fils EMG (&lt;10 Hz), et les artefacts haute fréquence à partir de l&#39;environnement (&gt; 500 Hz), sont supprimés. Utilisez un filtre coupe-bande de 60 Hz si il n&#39;y a aucune interférence de l&#39;alimentation de l&#39;ordinateur ou le système EMG. </li><li> Une fois que le signal a été filtré, de déterminer l&#39;amplitude du signal en calculant la valeur quadratique moyenne du signal: la place de chacun des points de données, de les additionner, diviser par le nombre de points de données, puis prendre la racine carrée de la valeur résultante. Effectuer ces calculs en utilisant le logiciel mentionné ci-dessus. </li></ol></li></ol> 8. Déterminer le seuil EMG de fatigue pour chaque participant <ol><li> Effectuez les étapes suivantes pour chaque participant. <ol><li> Après le signal EMG a été traitée; utiliser un programme statistique (par exemple: GraphPad Prism) et étiqueter la première colonne &quot;Time&quot; et les colonnes suivantes avec les sorties de puissance utilisés pour le test. </li><li> Pour chaque puissance, remplissez-en la valeur d&#39;amplitude correspondante EMG pour chaque intervalle de 20 secondes. </li><li> Pour chaque puissance, analyser le temps (axe des x) en fonction de l&#39;amplitude EMG (axe des y) en relation de régression linéaire pour déterminer si la pente de la droite de régression est significative (p &lt;0,05) différent de zéro. </li><li> Après avoir effectué les analyses de la régression linéaire pour toutes les sorties de puissance, identifier la puissance de sortie la plus élevée avec une pente non significatif (p&gt; 0,05). </li><li> Ensuite, identifier la ldois-puissance du moteur avec une pente significative (p &lt;0,05). </li><li> Une fois ces deux niveaux de puissance ont été identifiés, ajoutez-les et divisez par 2; la puissance de sortie résultante est le seuil de fatigue EMG approximative. </li></ol></li></ol>

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The authors have nothing to disclose.

Nous présentons ici une méthode pour déterminer la fatigue neuromusculaire dans les muscles quadriceps d&#39;exercice dynamique. Cette méthode offre une approche simple et non invasive à l&#39;aide de l&#39;EMG de surface. En outre, la polyvalence de cette méthode est que les chercheurs puissent l&#39;adapter à d&#39;autres modes d&#39;exercice comme le tapis roulant 20. Théoriquement, pour des intensités égales ou inférieures au seuil de fatigue EMG le participant doit...

L&#39;électromyographie de surface (EMG) est une approche non invasive d&#39;étudier le recrutement de moteur de l&#39;appareil pendant 1-3 isométrique, isocinétique 4-6, ou continue l&#39;action 7-10 musculaire. L&#39;amplitude du signal EMG représente l&#39;activation des muscles qui se compose du nombre d&#39;unités motrices est activé, la vitesse de l&#39;unité de mise à feu du moteur, ou les deux 11. Le concept du seuil de fatigue EMG est utilisé pour indiquer la plus haute charge de travail dans laquelle un individu peut exercer indéfiniment sans une augmentation de l&#39;amplitude EMG 8. Il est important de discussion brièvement l&#39;origine du seuil de fatigue EMG. L&#39;étude originale de Vries et al. 12 impliqué un protocole qui est composée de multiples (généralement 3 à 4) matchs de travail discontinus, où l&#39;amplitude EMG a été tracée en fonction du temps pour chaque combat de travail. La puissance de sortie est ensuite tracée en fonction des coefficients de pente de l&#39;amplitude EMG par rapport rela temps<html> rela-, et extrapolée à zéro pente (l&#39;ordonnée à l&#39;origine) 12. Les auteurs 12 initialement appelés ce protocole la capacité de travail physique sur le seuil de la fatigue (PWCFT). Dans une autre étude, de Vries et al. 13 utilisé épisodes de travail discontinus, mais utilisé la régression linéaire pour trouver la première puissance de sortie qui a abouti à une pente importante pour l&#39;amplitude EMG par rapport relation de temps. Les auteurs 13 aussi appelés ce protocole le PWCFT, créant une certaine confusion dans la littérature. Dans un article ultérieur, DeVries et al. 14 modifié leur protocole antérieur 13 et a développé un protocole incrémentale continue. L&#39;amplitude EMG a été tracée en fonction du temps pour chaque puissance du moteur et la PWCFT a été définie comme étant la moyenne de la puissance de sortie la plus élevée qui a donné lieu à aucun changement dans EMG amplitude au fil du temps et la puissance de sortie la plus faible qui a abouti à une augmentation de l&#39;amplitude au cours du temps EMG 14 . ent &quot;&gt; Il convient de noter que le terme PWC a été initialement introduit dans la fin des années 1950 15,16 et est synonyme avec une pléthore de littérature (passé, présent, et entre les différents pays) d&#39;examiner la capacité aérobie à une charge de travail donnée 17. En outre, le terme est utilisé dans la littérature ergonomique et industrielle qui se concentrent sur ​​la productivité des travailleurs effectuant action répétitive pendant les jours de travail de 8 heures de jour en jour comme les personnes dans une usine d&#39;assemblage 18. Le seuil de la fatigue de l&#39;EMG terme a d&#39;abord été utilisé par Matsumoto et ses collègues 19 après avoir modifié le 12 deVries protocole où la puissance de sortie par rapport coefficients de l&#39;amplitude EMG par rapport relation de temps de pente sont tracées et extrapolée au point de pente nulle. Plus récemment, Guffey et al. 20 et Briscoe et al. 8 utilise la méthode de Vries et al. 14 et la terminologie de Matsumoto et unl. 19 pour définir opérationnellement le seuil de fatigue EMG. Aller de l&#39;avant, nous recommandons que le terme seuil de fatigue EMG être utilisé. Ainsi, l&#39;amplitude EMG par rapport à la relation de temps est tracée pour chaque puissance du moteur, puis analysée en utilisant des analyses de régression linéaire (figure 1). Pour estimer le seuil de fatigue EMG, la puissance de sortie la plus élevée avec un (p&gt; 0,05) pente non significative et la plus faible puissance de sortie avec une réduction significative (p &lt;0,05) la pente est identifié et ensuite la 14 moyenne est calculée. Ce protocole est simple, pratique, et achevé dans 15-20 min. En outre, le taux d&#39;augmentation peut être modulé en fonction du niveau d&#39;activité physique habituelle de l&#39;individu, et a donc des applications potentielles dans les milieux cliniques.

<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

Théoriquement, l&#39;électromyographie (EMG) seuil de fatigue est l&#39;intensité de l&#39;exercice un individu peut maintenir indéfiniment sans la nécessité de recruter davantage d&#39;unités de moteur qui est associée à une augmentation de l&#39;amplitude EMG. Bien que différents protocoles ont été utilisées pour estimer le seuil de fatigue EMG ils nécessitent plusieurs visites qui ne sont pas pratiques pour un environnement clinique. Ici, nous présentons un protocole pour estimer le seuil de fatigue EMG pour ergocycle qui nécessite une seule visite. Ce protocole est simple, pratique, et achevé dans 15-20 min, par conséquent, a le potentiel pour être traduit en un outil que les cliniciens peuvent utiliser dans la prescription d&#39;exercice.

Comme le montre la Figure 1, pour un seul participant, chaque puissance du moteur qui est complétée comporte six points de données qui représentent l&#39;amplitude EMG pour le muscle vaste externe. Par conséquent, dans cet exemple, la puissance de sortie la plus élevée avec un non-significative (p&gt; 0,05) est incliné 200 watts, tandis que la plus faible puissance de sortie avec une réduction significative (p &lt;0,05) est incliné 225 W. Par conséquent, pour ce participant ...

Watch this Scientific Journal Video about Determining The Electromyographic Fatigue Threshold Following a Single Visit Exercise Test at JoVE.com

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.

Déterminer le seuil électromyographique fatigue après un test d&#39;exercice simple visite

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

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Research

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Medicine

12.4K vues.  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.

Vidéo: 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.

Faire sens de l&#39;écoute: la batterie de test 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 ...

Recherche

Médecine

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.

Le protocole social Trèves Stress Test pour induire un stress psychologique

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.

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.

Évaluation échographique de la fonction endothéliale: Une ligne directrice technique du Dilatation Test de débit à médiation

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.

Protocole expérimental d&#39;un essai d&#39;exercices de manivelle à trois minutes et à tous les bras dans les individus blessés et sans douleur de la moelle épinière

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.

Une Technique de biopsie du tissu adipeux sous-cutané Abdominal via une méthode Non-diathermie

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.

: Goût un brève et validé Test examen

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.

« Boden nourriture Plate » : nouvelle méthode Interactive sur le Web pour l’évaluation des apports alimentaires

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.

Réalisation d’un exercice d’Endurance maximale et sous-maximale tests pour mesurer les réponses physiologiques et biologiques à un exercice aigu chez l’homme

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;

Installation et exécution de l’exercice d’entraînement de Code les yeux bandés

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