1 |
The Use and Perceived Effectiveness of Recovery Modalities and Monitoring Techniques in Elite SportMelina Simjanovic Unknown Date (has links)
Post-exercise recovery techniques are being used increasingly in elite sport, but scientific study in this area is only emerging. The aim of this study was to collect information on the use and perceived effectiveness of the different recovery techniques used with athletes. Semi-structured interviews were conducted with 14 Queensland Academy of Sport coaches and other high-performance coaches from seven sports (three team sports and four individual sports). The interview questions sought to examine the coaches’ understanding of recovery, personal experiences, and the modalities and techniques used with their athletes. Interviews lasted an average of 45 minutes and were transcribed for qualitative content analysis and checked for accuracy by the coaches. Triangular consensus was used throughout the coding process to constantly revisit and redefine the open and axial codes that emerged. Three themes emerged: understanding of recovery, recovery modalities used, and monitoring of recovery. Understanding of recovery relates to the coaches’ overall view and general understanding of recovery. Coaches reported that recovery consisted of physical, mental and neural components, and is important to the overall performance, repeated performance, and training of athletes. Coaches gained their recovery knowledge from a variety of sources across their own athlete and coaching pathways. Transferring this knowledge to athletes was perceived as important for enabling athletes to implement and adhere to recovery within their training plans. The recovery modalities used most often were low-intensity activity, stretching, nutrition, massage, contrast water immersion, cryotherapy, sleep and rest. Practicality and accessibility (e.g., time and cost) for the athletes’ daily training environment were key factors influencing use of different recovery modalities. Coaches reported that they applied recovery modalities according to their own past coaching experiences or experiences of other coaches and sport science professionals. It appeared that coaches learn recovery information best by watching and speaking with others, especially other coaches and sports personnel. Factors contributing to use of recovery modalities include convenience and accessibility of a modality. Time restraint was an evident factor. Other factors that seem to contribute to the use of recovery modalities include the awareness of a modality’s existence, perceived modality strength of effect (or negative effect), and the compliance with and attitude of athletes to the modality. The personal experience of a coach using specific recovery modalities also impacted on whether the coach prescribed the modality and encouraged athletes to use the modality. However, it was clear from the study that athletes need to take responsibility for applying the recovery modalities themselves mainly because of logistical reasons. Recovery was monitored most often through informal observation rather than formal investigation. The most common monitoring approaches were coach observation and athlete reporting (diaries and discussions). Some coaches indicated that using a combination of approaches is useful and effective for gaining maximal benefits. Further investigation of monitoring approaches and prioritising them in terms of ease of implementation are needed. In summary, this study provided insight into the use of recovery modalities in elite sport and implications for use by professionals assisting coaches and athletes. In light of the limited research in some areas of recovery, a network could be established to capture the coaches’ learned experiences and information on recovery to share with each other across different sports.
|
2 |
MPLS-based recoveryMüller, Karen E 12 1900 (has links)
Thesis (MSc)--Stellenbosch University, 2003. / ENGLISH ABSTRACT: MPLS-based recovery is intended to effect rapid and complete restoration of traffic affected by a fault
in a Multiprotocol Label Switching (MPLS) network. Two MPLS-based recovery models have been
proposed: lP re-routing which establishes recovery paths on demand, and protection switching which
works with pre-established recovery paths. lP re-routing is robust and frugal since no resources are
pre-committed but it is inherently slower than protection switching which is intended to offer high
reliability to premium services where fault recovery takes place at the 100 ms time scale.
This thesis presents an overview of various recovery techniques and addresses the problem of how to
find an in some sense optimal set of pre-established traffic engineered recovery paths, given a network
with link capacities and traffic demands.
We present and motivate our choice of a nonlinear objective function and optimization method for
finding traffic engineered working and recovery paths. A variant of the flow deviation method is used
to find and capacitate a set of optimal label switched paths. We present and evaluate two simple
methods for computing a set of pre-established traffic engineered recovery paths by using the flow
deviation method. / AFRIKAANSE OPSOMMING: MPLS-gebaseerde herstel is daarop gemik om verkeer wat deur 'n fout in 'n Multiprotokol Etiketwisseling
(Multiprotocol Label Switching) (MPLS) netwerk geaffekteer is, vinnig en volledig te herstel.
Twee MPLS-gebaseerde herstelmodelle is voorgestel: Internetprotokol-herroetering (lP rerouting)
wat herstelpaaie op aanvraag tot stand bring, en beskermingsoorskakeling (protection switching)
wat met voorafbeplande herstelpaaie werk. IP-herroetering is robuust en voordelig aangesien
geen netwerkbronne vooraf gereserveer word nie, maar dit is inherent stadiger as beskermingsoorskakeling
wat veronderstel is om 'n hoë graad van betroubaarheid aan belangrike dienste te bied waar die
herstel van foute in die 100 ms tydskaal plaasvind.
Hierdie tesis verskaf 'n oorsig oor verskeie hersteltegnieke en ondersoek die probleem hoe om 'n
optimale versameling van voorafbeplande herstelpaaie te vind, gegee 'n netwerk met skakelkapasiteite
(link capacities) en verwagte netwerkverkeer.
Ons stel voor en motiveer ons keuse van 'n nie-lineêre objekfunksie en optimeringsmetode om verkeersontwerpde
(traffic engineered) aktiewe en herstelpaaie te vind. 'n Variant van die vloeideviasie
(flow deviation)-metode word gebruik om 'n optimale versameling van etiketwisseling (label
switched) paaie te vind en om 'n optimale hoeveelheid kapasiteit aan die paaie toe te ken. Ons stel
voor en evalueer twee eenvoudige metodes om 'n versameling van optimale voorafbeplande herstelpaaie
te bereken deur die vloeideviasie-metode toe te pas.
|
3 |
Analysis of an Energy Recovery VentilatorHilmersson, Anders, Paulsson, Ulf January 2006 (has links)
<p>Energy recovering techniques for air conditioning has increased in recent years and new prod- </p><p>ucts have been introduced to the market where the Membrane-based Energy Recovery Ventilator </p><p>(ERV) is one promising product. The aim of this study was to evaluate a new type of membrane </p><p>material for an ERV and give an analysis of the need for digital control of the air flow rate to </p><p>improve efficiency. A prototype counter-flow ERV was used in the test to validate the performance under different </p><p>flow conditions. The result was promising for the tested membrane material with high moisture </p><p>and heat transfer. The optimisation of the flow rate was found to be superfluous, since the relation </p><p>between the energy transferred by the ERV and the air flow rate was almost linear.</p>
|
4 |
Analysis of an Energy Recovery VentilatorHilmersson, Anders, Paulsson, Ulf January 2006 (has links)
Energy recovering techniques for air conditioning has increased in recent years and new prod- ucts have been introduced to the market where the Membrane-based Energy Recovery Ventilator (ERV) is one promising product. The aim of this study was to evaluate a new type of membrane material for an ERV and give an analysis of the need for digital control of the air flow rate to improve efficiency. A prototype counter-flow ERV was used in the test to validate the performance under different flow conditions. The result was promising for the tested membrane material with high moisture and heat transfer. The optimisation of the flow rate was found to be superfluous, since the relation between the energy transferred by the ERV and the air flow rate was almost linear.
|
5 |
From Midden to Sieve: The Impact of Differential Recovery and Quantification Techniques on Interpretations of Shellfish Remains in Australian Coastal ArchaeologyJenkins, Robyn Unknown Date (has links)
Experimental mechanical sieving methods are applied to samples of shellfish remains from three sites in southeast Queensland, Seven Mile Creek Mound, Sandstone Point and One-Tree, to test the efficacy of various recovery and quantification procedures commonly applied to shellfish assemblages in Australia. There has been considerable debate regarding the most appropriate sieve sizes and quantification methods that should be applied in the recovery of vertebrate faunal remains. Few studies, however, have addressed the impact of recovery and quantification methods on the interpretation of invertebrates, specifically shellfish remains. In this study, five shellfish taxa representing four bivalves (Anadara trapezia, Trichomya hirsutus, Saccostrea glomerata, Donax deltoides) and one gastropod (Pyrazus ebeninus) common in eastern Australian midden assemblages are sieved through 10mm, 6.3mm and 3.15mm mesh. Results are quantified using MNI, NISP and weight. Analyses indicate that different structural properties and pre- and postdepositional factors affect recovery rates. Fragile taxa (T. hirsutus) or those with foliated structure (S. glomerata) tend to be overrepresented by NISP measures in smaller sieve fractions, while more robust taxa (A. trapezia and P. ebeninus) tend to be overrepresented by weight measures. Results demonstrate that for all quantification methods tested a 3mm sieve should be used on all sites to allow for regional comparability and to effectively collect all available information about the shellfish remains.
|
6 |
From Midden to Sieve: The Impact of Differential Recovery and Quantification Techniques on Interpretations of Shellfish Remains in Australian Coastal ArchaeologyJenkins, Robyn Unknown Date (has links)
Experimental mechanical sieving methods are applied to samples of shellfish remains from three sites in southeast Queensland, Seven Mile Creek Mound, Sandstone Point and One-Tree, to test the efficacy of various recovery and quantification procedures commonly applied to shellfish assemblages in Australia. There has been considerable debate regarding the most appropriate sieve sizes and quantification methods that should be applied in the recovery of vertebrate faunal remains. Few studies, however, have addressed the impact of recovery and quantification methods on the interpretation of invertebrates, specifically shellfish remains. In this study, five shellfish taxa representing four bivalves (Anadara trapezia, Trichomya hirsutus, Saccostrea glomerata, Donax deltoides) and one gastropod (Pyrazus ebeninus) common in eastern Australian midden assemblages are sieved through 10mm, 6.3mm and 3.15mm mesh. Results are quantified using MNI, NISP and weight. Analyses indicate that different structural properties and pre- and postdepositional factors affect recovery rates. Fragile taxa (T. hirsutus) or those with foliated structure (S. glomerata) tend to be overrepresented by NISP measures in smaller sieve fractions, while more robust taxa (A. trapezia and P. ebeninus) tend to be overrepresented by weight measures. Results demonstrate that for all quantification methods tested a 3mm sieve should be used on all sites to allow for regional comparability and to effectively collect all available information about the shellfish remains.
|
7 |
Modalités d'exercice et de récupération : approche cardiovasculaire et performance / Exercises modalities and recovery strategies : cardiovascular aspects and performanceMénétrier, Arnaud 06 December 2013 (has links)
(Cf. corpus p. 25-26) Ce travail de thèse s'est articulé autour de deux problématiques : les réponses cardiovasculaires consécutives à l/ différents protocoles d'exercice et 2/ différents protocoles de récupération. Concernant la première, 3 protocoles de recherches ont été menés. L'un avait pour objectif de déterminer les effets aigus d'exercices de même durée proposant une quantité de travail totale équivalente distribuée de façon constante (CC) ou intermittente (IT), sur la rigidité artérielle multi-segmentaire et ses déterminants. Les deux autres se proposaient d'explorer les dysfonctions cardiaques induites par des exercices de durées plus longues (2 à 4 heures) et leurs mécanismes sous-jacents. La seconde problématique de ce travail de doctorat a conduit à la réalisation de 5 protocoles de recherche. L'immersion contrastée (alternance d'immersions d'une à deux minutes jusqu'à l'aine à ~ 12°C et à ~ 36°C), l'immersion en eau froide (~ 12°C) et la compression élastique ont été tout particulièrement étudiées. Les points suivants ont été abordés : la comparaison des effets de la compression élastique et de l'immersion contrastée sur la performance subséquente ; la connaissance des facteurs concourant aux bénéfices de ces dernières entre des efforts intenses et brefs (c.-à-d. étude du débit sanguin musculaire, de la saturation tissulaire en oxygène, de la clairance des métabolites, etc.) ; l'étude des effets de la pression hydrostatique seule (immersion à neutralité thermique ), et ceux de celle-ci associée au froid (immersion en eau froide ) ou à l'alternance de température (immersion contrastée) sur le débit sanguin musculaire; et enfin l'étude des effets sur certains paramètres de la récupération du port d'une compression élastique au cours et au décours d'un trail. Dans ce contexte, les résultats de nos études mettent en évidence qu'un exercice de type IT diminue davantage la rigidité artérielle multi-segmentaire qu'un exercice de type CC. Cette diminution plus prononcée est associée à un relargage plus important de substances vasodilatatrices (NO,ANP, lactates, etc.). Nous avons également montré qu'un exercice prolongé de durée modérée engendre des dysfonctions cardiaques transitoires. Plus particulièrement, certains indices de contractilité évalués par une technique échocardiographique de dernière génération (c.-à-d. le « Speckle Tracking Echocardiography ») nous ont permis de mettre en évidence que la baisse de la fonction systolique du ventricule gauche (VG) était associée à une atteinte contractile du myocarde dans des conditions standardisées de fréquence et de charge cardiaques. Nos résultats soulignent également le rôle clé de la torsion ventriculaire dans la diminution du remplissage du VG et par conséquent de la fonction diastolique à l'arrêt de l'effort. Les études expérimentales s'intéressant aux techniques de récupération post-exercice indiquent que l'immersion contrastée et la compression élastique par rapport à une récupération passive, lorsqu'elles sont appliquées immédiatement après un premier exercice fatiguant, améliorent la performance subséquente (exercice de pédalage de 5 min) lorsque celle-ci est répétée dans un laps de temps court (15 min). De plus, l'immersion contrastée est plus efficace que la compression élastique pour améliorer la performance subséquente. Ces techniques de récupération accélèrent la clairance du lactate, cette dernière étant accélérée davantage après l'immersion contractée. La compression élastique augmente le débit sanguin musculaire mais également la saturation tissulaire en oxygène, que ce soit avant et après l'effort. Par rapport à une récupération passive, l'immersion contrastée augmente également le débit sanguin musculaire après l'effort, et davantage que la compression élastique. (...) / (Cf. corpus p. 27-28) This thesis work focuses on the cardiovascular responses consecutive to l/ various exercice modalities and 2/ various post-exercise recovery interventions. With regard to the exercise modalities, 3 experimental protocols were led. The first one aimed to compare the acute effects of constant and interval exercises on regional arterial stiffness and these determinants. Two others studies focused on the cardiac dysfunctions induced by exercises of longer durations (2-3h) and the underlying mechanisms. The second problematic of this thesis work led to 5 studies. The following questions were approached: the comparison of the effects of contrast water therapy and compression stockings on the subsequent performance; the knowledge of the factors at the origin of the benefits of these recovery interventions between repeated brief and exhaustive bouts of physical exercise (i.e. muscle blood flow, muscle oxygenation, removal of metabolic waste, etc.) ; the changes in leg muscle blood flow, caused by hydrostatic pressure alone [thermoneutral water immersion), and in addition to cooling (cold water immersion) or alternating of temperature (contrast water therapy); and finally the effects of elastic compression worn during and after a trail running race on the participants' recovery. Our results show that interval exercise decreases more regional arterial stiffness [central and peripheral) than constant exercise. This more pronounced decrease is associated with a higher concentration of vasodilator factors (NO, ANP, lactates, etc.). We also show that a prolonged exercise (2-3h) induce transient cardiac dysfunctions. Specifically, parameters of systolic function evaluated using 2D-speckle tracking echocardiography not only at rest, but also during incremental tests to adjust heart rate demonstrate that the 3h-period of prolonged and strenuous exercise induces left ventricular systolic dysfunction. Our results also demonstrate that depressed diastolic function is associated with delayed untwisting velocity. The studies focusing on post-exercise recovery interventions indicate that compared with passive recovery, contrast water therapy and compression stockings improve the subsequent 5-min maximal performance in cycling when this one is repeated during a brief elapsed time (i.e. 15 min). Moreover, contrast water therapy is more efficient than compression stockings to improve the subsequent performance. Theses recovery interventions accelerate the removal of lactates, and contrast water therapy more than compression stockings. The elastic compression increases muscle blood flow but also tissue oxygen saturation, before and after a physical exercise. Contrast water therapy also increases muscle blood flow after an exercise compared with a passive recovery, and more than elastic compression. (...)
|
Page generated in 2.1618 seconds