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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Efeito do pré-condicionamento isquêmico em sprints repetidos / The effect of ischemic preconditioning in repeated sprints

Salvador, Amadeo Félix 06 August 2015 (has links)
Made available in DSpace on 2016-12-06T17:07:05Z (GMT). No. of bitstreams: 1 Amadeo Salvador.pdf: 110618 bytes, checksum: 6f34d5dc9709e800b89a028ee6734d40 (MD5) Previous issue date: 2015-08-06 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Intermittent sports require maximum effort interspersed with short periods of recovery that are usually called repeated sprints (SR). In order to improve the SR on competition day, various methods are used, however a method that research is growing is the ischemic preconditioning (IPC). The PCI is the intermittent application of a pressure value in the proximal portion of a preset limb. The aim of the study was to evaluate the effect of PCI on SR performance and related physiological variables. Seven female players (26 ± 3 years, 65.9 ± 8 kg and 161 ± 4 cm) and six male players (21 ± 3 years 77.8 ± 6 kg and 179 ± 7 cm) of sevens rugby conducted randomly four test SR being two preceded by PCI and two by control condition (CTRL). The SR were analyzed in pairs being the end of each pair collected the rating of perceived exertion (PSE). Treatment with PCI showed substantial improvement in the average time of SR (CTRL: 3.31 × / ÷ 2.1 and PCI: 3.25 × / ÷ 2.2 s, p = 0.001) and in the best sprint (CTRL: 3.20 × / ÷ 3.1 and PCI: 3.12 × / ÷ 3.3 s, p = 0.009) for men. However these same variables were not significantly different in women (average time: CTRL: 3.76 × / ÷ 1.4 and PCI: 3.73 × / ÷ 1.5 s, p = 0.15) and (best sprint: CTRL: 3.62 × / ÷ 2.1 to PCI: 3.66 × / ÷ 2.1 s, p = 0.24). When controlled for the initial PSE, PSE also demonstrated significant difference for men (CTRL: 15 ± 0.7 and PCI: 13.9 ± 0.7, p = 0.04) and did not show for women (CTRL: 14.4 and PCI ± 0.7: 13.8 ± 0.7, p = 0.25). Therefore, the PCI is a beneficial strategy for improving performance in SR test in men, but further studies are needed to better understand the PCI treatment relationship in men and women. / Esportes intermitentes requerem esforços máximos intercalados com curtos períodos de recuperação que são geralmente denominados sprints repetidos (SR). Com intuito de melhorar o SR no dia da competição, vários métodos são utilizados, entretanto um método em crescente investigação é o précondicionamento isquêmico (PCI). O PCI consiste na aplicação intermitente de um valor de pressão na porção proximal de um membro pré-definido. O objetivo do estudo foi avaliar o efeito do PCI no desempenho do SR e variáveis fisiológicas relacionadas. Sete jogadoras (26 ± 3 anos, 65,9 ± 8 kg e 161 ± 4 cm) e seis jogadores (21 ± 3 anos 77,8 ± 6 kg e 179 ± 7 cm) de rugby sevens realizaram de forma randomizada quatro testes de SR sendo dois precedidos de PCI e dois em condição controle (CTRL). Os SR foram analisados em pares sendo ao fim de cada par coletada a percepção subjetiva de esforço (PSE). O tratamento com PCI apresentou melhora substancial no tempo médio do SR (CTRL: 3,31 ×/÷ 2,1 s e PCI: 3.25 ×/÷ 2.2 s, p=0.001) e no melhor sprint (CTRL: 3,20 ×/÷ 3.1 s e PCI: 3,12 ×/÷ 3,3 s, p=0.009) para os homens. Entretanto estas mesmas variáveis não apresentaram diferenças significativas nas mulheres (tempo médio: CTRL: 3,76 ×/÷ 1,4 s e PCI: 3,73 ×/÷ 1,5 s, p=0,15) e (melhor sprint: CTRL: 3,62 ×/÷ 2,1 s e PCI: 3,66 ×/÷ 2,1 s, p=0,24). Quando controlado pela PSE inicial, a PSE também demostrou diferença significativa para os homens (CTRL: 15 ± 0,7 e PCI: 13.9 ± 0,7, p=0,04) e não demostrou para as mulheres (CTRL: 14,4 ± 0,7 e PCI: 13,8 ± 0,7, p=0,25). Portanto, o PCI é uma estratégia benéfica para melhora do desempenho em teste de SR em homens, porém futuros estudos são necessários para entender melhor a relação do tratamento de PCI em homens e mulheres.
12

Correlações da aptidão aeróbia e de fatores neuromusculares no desempenho em sprints repetidos em tenistas de diferentes níveis competitivos / Correlations of aerobic fitness and neuromuscular factors with repeated sprints performance in tennis players of different competitive level

Urso, Rodrigo Poles 13 February 2015 (has links)
O objetivo desse estudo foi verificar a relação da aptidão aeróbia e de fatores neuromusculares com o desempenho em SR em tenistas com diferentes níveis de jogo. Um grupo de dez tenistas profissionais (GP) e um grupo de dez tenistas amadores (GA) foram submetidos a quatro sessões experimentais, a saber: 1) medidas antropométricas, familiarização com o teste de drop jump (DJ) e com o teste de contração voluntária isométrica máxima (CVIM) para membros inferiores, e um teste progressivo até a exaustão; 2) um teste de DJ e um teste de carga constante para avaliar a cinética on e off do consumo de oxigênio (VO2); 3) um teste de CVIM para membros inferiores, outro teste de carga constante para avaliar a cinética on e off do VO2 e familiarização com o teste de SR; 4) um teste composto por dez SR. O GP apresentou valores significativamente menores para o tempo do melhor sprint (SRmelhor) e para a média dos tempos de todos os sprints (SRmédio) em relação ao GA (p < 0,05). O percentual de aumento do tempo ao longo dos sprints (SR%aumento) do GP não foi significativamente menor em comparação ao GA (p = 0,102), porém a chance dessa variável ser menor para o GP foi considerada \"provável\". Para o GP, a única correlação significativa observada foi entre o SRmédio e o tempo de contato obtido no teste de DJ (r = 0,641, p < 0,05). Em relação ao GA, foram observadas correlações significativas da velocidade pico obtida no teste progressivo até a exaustão com o SRmelhor (r = -0,680, p < 0,05) e SRmédio (r = -0,744, p < 0,05), assim como da amplitude da fase lenta da cinética off do VO2 com o SRmelhor (r = -0,756, p < 0,05) e SRmédio (r = -0,794, p < 0,05). Portanto, esses dados sugerem que tenistas profissionais possuem um melhor desempenho em SR em comparação aos tenistas amadores. Entretanto, não está clara a importância de fatores da aptidão aeróbia e neuromusculares no desempenho dessa atividade / The objective of this study was to verify the relationship of aerobic fitness and neuromuscular factors with RS performance in tennis players with different playing level. A group of ten professional (PG) and ten amateur (AG) tennis players were submitted to four experimental sessions, to know: 1) anthropometric measurements, familiarization with the drop jump (DJ) test and the maximal voluntary isometric contraction (MVIC) test for the lower limbs, and a progressive test until exhaustion; 2) a DJ test and a constant load test for on and off oxygen consumption (VO2) kinetics measurement; 3) a MVIC test for the lower limbs, another constant load test for on and off VO2 kinetics measurement, and familiarization with the RS test; 4) a test of ten RS. The PG presented significant lower values for the best sprint time (RSbest) and mean time of all sprints (RSmean) in relation to the AG (p < 0.05). The percentage increase in time over all sprints (RSincrease) of the PG was not significantly lower in comparison to the AG (p = 0.102), however the chance of this variable to be lower for the PG was considered \"probable\". For the PG the only significant correlation observed was between RSmean and the contact time obtained in the DJ test (r = 0.641, p < 0.05). In relation to the AG, significant correlations were observed for the peak speed obtained on the progressive test until exhaustion with the RSbest (r = -0.680, p < 0.05) and RSmean (r = -0.744, p < 0.05), likewise for the amplitude of the slow phase in oxygen uptake off-kinetics with the RSbest (r = -0.756, p < 0.05) and RSmean (r = -0.794, p < 0.05). Thus, these data suggest that professional tennis players have a better performance in RS compared to amateur tennis players. However, it is not clear the importance of aerobic fitness and neuromuscular factors in the performance of this activity
13

Étude des réponses physiologiques aiguës à l’exercice intermittent de haute intensité chez le patient insuffisant cardiaque

L.Normandin, Eve 12 1900 (has links)
L’optimisation de l’exercice par intervalles de haute intensité (EIHI) chez les patients insuffisants cardiaques (IC) n’a jamais été étudiée auparavant. Nous avons comparé les réponses cardio-pulmonaires aiguës lors de 4 différents EIHI dans le but de trouver le protocole optimisé chez les patients IC. Les patients IC étaient aléatoirement alloués à 4 sessions d’EIHI. Chaque phase d’exercice était à une intensité de 100% de la puissance aérobie maximale (PAM), mais de différentes durées (30s ou 90s) et de type de récupération (passive ou active). Chaque protocole d’EIHI durait un maximum de 30 minutes ou jusqu’à épuisement. Considérant le temps total d’exercice, l’adhérence, une perception d’effort moins élevée, le confort du patient ainsi que des temps similaires passés à un haut pourcentage du VO2pic, le mode avec intervalles courts (30s) et récupération passive s’est avéré être le protocole d’EIHI optimisé chez ces patients. Suite à cette étude, nous avons voulu comparer les réponses cardio-pulmonaires aiguës d’un exercice continu d’intensité modéré (ECIM) par rapport à celles de l’EIHI optimisé de dépense énergétique équivalente chez les patients IC. L’objectif de cette étude était de comparer les réponses cardio-pulmonaires, l’adhérence, la perception de l’effort, l’inflammation et les biomarqueurs cardiaques. Comparativement à l’ECIM, l’adhérence, l’efficience et la tolérance étaient plus élevées lors de l’EIHI optimisé chez les patients IC tout en produisant un stimulus physiologique important. L’EIHI n’a causé aucune arythmie significative ou d’effets délétères sur l’inflammation (CRP), le BNP et la nécrose myocardique (C-TnT) chez les patients IC. L’EIHI semble être un mode d’exercice prometteur et devrait être considéré lors de la réadaptation cardiaque chez les patients IC. / Optimization of high intensity interval exercise (HIIE) in patients with chronic heart failure (CHF) has never been studied. We have compared the acute cardiopulmonary responses to four different HIIE in order to optimized HIIE protocol in CHF patients. Patients with CHF were randomized to 4 HIIE sessions, all with exercise phases at 100% of maximal aerobic power (MAP), but which varied in interval duration (30s or 90s) and type of recovery (passive or active). Each HIIE protocol lasted until exhaustion or up to 30 minutes. When considering total exercise time, exercise adherence, lower perceived exertion ratings, patient’s comfort and similar time spent at a high percentage of VO2peak, the mode with short intervals (30s) and passive recovery appeared to be the optimal HIIE mode for these patients. We therefore sought to compare the acute cardiopulmonary responses of a moderate intensity continuous exercise (MICE) compared to an optimized HIIE of equal total energy expenditure in patients with CHF. The purpose of this study was to compare cardiopulmonary responses, exercise adherence, perceived exertion, inflammation and cardiac biomarkers measured on optimized HIIE compared to MICE in patients with CHF. Compared to MICE, HIIE showed a higher exercise adherence, was more efficient and well tolerated by CHF patients while still providing a high physiological stimulus. HIIE did not induced significant arrhythmias or deleterious effects on inflammation (CRP), BNP and myocardial necrosis (C-TnT) in patients with CHF. We conclude that HIIE is a promising training mode that should be considered for cardiac rehabilitation interventions in patient with CHF.
14

Correlações da aptidão aeróbia e de fatores neuromusculares no desempenho em sprints repetidos em tenistas de diferentes níveis competitivos / Correlations of aerobic fitness and neuromuscular factors with repeated sprints performance in tennis players of different competitive level

Rodrigo Poles Urso 13 February 2015 (has links)
O objetivo desse estudo foi verificar a relação da aptidão aeróbia e de fatores neuromusculares com o desempenho em SR em tenistas com diferentes níveis de jogo. Um grupo de dez tenistas profissionais (GP) e um grupo de dez tenistas amadores (GA) foram submetidos a quatro sessões experimentais, a saber: 1) medidas antropométricas, familiarização com o teste de drop jump (DJ) e com o teste de contração voluntária isométrica máxima (CVIM) para membros inferiores, e um teste progressivo até a exaustão; 2) um teste de DJ e um teste de carga constante para avaliar a cinética on e off do consumo de oxigênio (VO2); 3) um teste de CVIM para membros inferiores, outro teste de carga constante para avaliar a cinética on e off do VO2 e familiarização com o teste de SR; 4) um teste composto por dez SR. O GP apresentou valores significativamente menores para o tempo do melhor sprint (SRmelhor) e para a média dos tempos de todos os sprints (SRmédio) em relação ao GA (p < 0,05). O percentual de aumento do tempo ao longo dos sprints (SR%aumento) do GP não foi significativamente menor em comparação ao GA (p = 0,102), porém a chance dessa variável ser menor para o GP foi considerada \"provável\". Para o GP, a única correlação significativa observada foi entre o SRmédio e o tempo de contato obtido no teste de DJ (r = 0,641, p < 0,05). Em relação ao GA, foram observadas correlações significativas da velocidade pico obtida no teste progressivo até a exaustão com o SRmelhor (r = -0,680, p < 0,05) e SRmédio (r = -0,744, p < 0,05), assim como da amplitude da fase lenta da cinética off do VO2 com o SRmelhor (r = -0,756, p < 0,05) e SRmédio (r = -0,794, p < 0,05). Portanto, esses dados sugerem que tenistas profissionais possuem um melhor desempenho em SR em comparação aos tenistas amadores. Entretanto, não está clara a importância de fatores da aptidão aeróbia e neuromusculares no desempenho dessa atividade / The objective of this study was to verify the relationship of aerobic fitness and neuromuscular factors with RS performance in tennis players with different playing level. A group of ten professional (PG) and ten amateur (AG) tennis players were submitted to four experimental sessions, to know: 1) anthropometric measurements, familiarization with the drop jump (DJ) test and the maximal voluntary isometric contraction (MVIC) test for the lower limbs, and a progressive test until exhaustion; 2) a DJ test and a constant load test for on and off oxygen consumption (VO2) kinetics measurement; 3) a MVIC test for the lower limbs, another constant load test for on and off VO2 kinetics measurement, and familiarization with the RS test; 4) a test of ten RS. The PG presented significant lower values for the best sprint time (RSbest) and mean time of all sprints (RSmean) in relation to the AG (p < 0.05). The percentage increase in time over all sprints (RSincrease) of the PG was not significantly lower in comparison to the AG (p = 0.102), however the chance of this variable to be lower for the PG was considered \"probable\". For the PG the only significant correlation observed was between RSmean and the contact time obtained in the DJ test (r = 0.641, p < 0.05). In relation to the AG, significant correlations were observed for the peak speed obtained on the progressive test until exhaustion with the RSbest (r = -0.680, p < 0.05) and RSmean (r = -0.744, p < 0.05), likewise for the amplitude of the slow phase in oxygen uptake off-kinetics with the RSbest (r = -0.756, p < 0.05) and RSmean (r = -0.794, p < 0.05). Thus, these data suggest that professional tennis players have a better performance in RS compared to amateur tennis players. However, it is not clear the importance of aerobic fitness and neuromuscular factors in the performance of this activity
15

Condition physique objective et perçue chez l’adolescent obèse : évaluation et prise en charge par l’exercice intermittent d’intensité vigoureuse / Objective and perceived physical condition in obese adolescents : assessment and follow-up by vigorous intensity intermittent exercise

Rey, Olivier 01 December 2016 (has links)
Cette thèse porte sur l’évaluation et la prise en charge par l’activité physique d’adolescent(e)s obèses. Deux études ont quantifié leurs réponses psychophysiologiques à un test de course intermittent en 15-15 (Rossi et al., 2009), progressif et maximal. Comparé au test navette de 20m (Léger et al., 1988), la pertinence du test 15-15 pour cette population réside dans la production de réponses physiologiques maximales similaires tout en conduisant à des vitesses supérieures et à une meilleure condition physique perçue. Deux autres études ont évalué les effets d’un programme de 5 semaines d’exercices intermittents d’intensité vigoureuse (VIT) sur la composition corporelle et les conditions physiques objective et perçue d’adolescents obèses. Le programme comprenait 3 séances hebdomadaires de types de VIT différant en durée et en activités physiques et sportives. Des améliorations de la composition corporelle, des capacités fonctionnelles, notamment chez les garçons, et de la plupart des échelles de capacités physiques perçues sont obtenues. Le VIT de longue durée engendre des améliorations rapides et régulières des échelles de capacités physiques perçues / This thesis fits the assessment and follow-up by physical activity of obese adolescents. Two studies measured their psychophysiological responses to an intermittent progressive and maximal running test in 15-15 (Rossi et al., 2009). Compared to the 20 m shuttle run test (Léger et al., 1988), the 15-15 test is considered as relevant for such population as it leads to similar maximal physiological responses, but also to higher speeds and better perceived physical condition of the participants. Two other studies evaluated the effects of a 5 week program of intermittent exercises at vigorous intensity (VIT) on body composition, objective and perceived physical conditions of obese adolescents. The program included 3 weekly VIT sessions that differed in the type and duration of the included sport and physical activities. Improvements were obtained in body composition, functional capacities, particularly among boys, and in most of the scales of perceived physical capacities. The longest VIT sessions led to rapid and regular improvements of all scales of perceived physical capacities
16

Étude des réponses physiologiques aiguës à l’exercice intermittent de haute intensité chez le patient insuffisant cardiaque

L. Normandin, Eve 12 1900 (has links)
No description available.
17

Étude de la réponse aiguë à l'exercice intermittent à haute intensité chez le patient coronarien

Guiraud, Thibaut 12 1900 (has links)
L'entraînement par intervalles à haute intensité est plus efficace que l'entraînement continu d’intensité modérée pour améliorer la consommation maximale d’oxygène (VO2max) et le profil métabolique des patients coronariens. Cependant, il n’y a pas de publications pour appuyer la prescription d’un type d’exercice intermittent (HIIE) spécifique dans cette population. Nous avons donc comparé les réponses aiguës cardio-pulmonaires de quatre sessions différentes d’exercice intermittent dans le but d’identifier l’exercice optimal chez les patients coronariens. De manière randomisée, les sujets participaient aux sessions d’HIIE, toutes avec des phases d’exercice à 100% de la puissance maximale aérobie (PMA), mais qui variaient selon la durée des phases d’exercice et de récupération (15s ou 1 min) et la nature de la récupération (0% de la PMA ou 50% de la PMA). Chaque session était réalisée sous forme de temps limite et l’exercice était interrompu après 35 minutes. En considérant l’effort perçu, le confort du patient et le temps passé au-dessus de 80% de VO2max, nous avons trouvé que l’exercice optimal consistait à alterner des courtes phases d’exercice de 15s à 100% de la PMA avec des phases de 15s de récupération passive. Ensuite, nous avons comparé les réponses physiologiques de l’HIIE optimisé avec un exercice continu d’intensité modérée (MICE) iso-calorique chez des patients coronariens. En considérant les réponses physiologiques, l’aspect sécuritaire (aucune élévation de Troponin T) et l’effort perçu, le protocole HIIE est apparu mieux toléré et plus efficace chez ces coronariens. Finalement, une simple session d’HIIE n’induit pas d’effets délétères sur la paroi vasculaire, comme démontré avec l’analyse des microparticules endothéliales. En conclusion, l’exercice intermittent à haute intensité est un mode d'entraînement prometteur pour les patients coronariens stables qui devrait faire l’objet d’autres études expérimentales en particulier pour les patients coronariens ischémiques. / High-intensity interval training has been shown to be more effective than moderate intensity continuous training for improving maximal oxygen uptake (VO2max) and metabolic profile in patients with coronary heart disease (CHD). However, no evidence supports the prescription of one specific protocol of high intensity interval exercise (HIIE) in this population. We have compared the acute cardiopulmonary responses to four different sessions of HIIE in order to identify the most optimal one in CHD patients. In random fashion, subjects performed the different HIIE sessions, all with exercise phases at 100% of maximal aerobic power (MAP), but which varied in interval duration (15 s or 60 s) and type of recovery (0% of MAP or 50% of MAP). Each protocol lasted 35 minutes or until exhaustion. When considering perceived exertion, patient comfort and time spent above 80% of VO2max, we found that repeated bouts of 15s at 100% of MAP interspersed by 15s phases of passive recovery was the optimal HIIE session for these coronary patients. Then, we compared the physiological responses to the optimized HIIE versus a moderate intensity continuous training (MICE) protocol of similar energy expenditure in coronary patients. When considering physiological responses, safety (no elevation of Troponin T) and perceived exertion, the HIIE protocol appeared to be well tolerated and more efficient in this group of stable coronary patients. Finally, a single bout of HIIE did not induce deleterious effects on the endothelium, as demonstrated by endothelial microparticules analyses. We conclude that high-intensity interval exercise is a promising mode of training for patients with stable CHD that should also be further investigated in cardiac patients, particularly with exercise-induced ischemia.
18

Applied physiology and game analysis of elite women's water polo

Tan, Frankie Hun Yau January 2010 (has links)
[Truncated abstract] Broadly, research literature on the physiological aspects of water polo game play is limited, but particularly so in the women's game. Moreover, significant changes to game rules in recent years are likely to have had an impact on the game demands. Therefore, this research project sought to investigate the physiological characteristics of contemporary elite female water polo players and the demands of match play. Overall, the five studies comprising this thesis aimed to improve the practical knowledge of coaches and sport scientists concerning the training and monitoring of players. Study one (Chapter 3) compared two water polo-specific field tests of aerobic and/or match fitness (MSST, multistage shuttle swim test; and WIST, water polo intermittent shuttle test) with a traditional incremental swimming test to exhaustion (IST, 5 x 200 m). Prior to this study, the physiological responses to the MSST and WIST were not well understood. Additionally, the degree of association between these two tests was unknown. Therefore, 14 Australian National Women's Water Polo Squad players performed the MSST and WIST, and 13 players from a National Water Polo League club performed the MSST, WIST and IST, on separate occasions. Peak heart rate, blood lactate and ratings of perceived exertion were obtained for all tests. Expired air was collected post test for the National League players. The results showed that the National Squad players performed significantly better in the MSST (636 ± 114 vs. 437 ± 118 m, p < 0.001) and WIST (270 ± 117 vs. 115 ± 57 m, p < 0.001) than the National League players. ... Absolute decrement yielded TE of 0.55 s (-0.42-0.81), CV of 26.0% (19.3-41.0) and ICC of -0.002 (-0.44-0.44). Relative (%) decrement yielded TE of 1.6% (1.2-2.3), CV of 27.2% (20.1-42.9) and ICC of -0.02 (-0.46-0.42). Results indicate that total time was a reliable measure, whilst decrement was not. Similar to land-based RSA tests, total time should be the criterion measure of performance in the RST. The RST can form part of a specific battery of field tests for water polo, and can also be used as a conditioning tool. The final study (Chapter 7) was a nutritional-intervention study. Based on the time-motion data from study three, a 59-min match simulation test (MST) was designed to mimic the activity profiles and physical demands of water polo match play. Using a randomized cross-over double-blind design, 12 Australian National Women's Water Polo Squad players ingested 0.3 g·kg-1 of NaHCO3 or placebo, 90 min before performing the MST, which included 56 x 10-m maximal-sprint swims as the performance measure. Although pre-exercise ingestion of NaHCO3 was effective in enhancing extracellular pH and bicarbonate levels, the percentage difference in mean sprint times between trials showed no substantial effects of NaHCO3 (0.4; ±0.9%, effect size = 0.09; ±0.23, p = 0.51). The results suggest that elite water polo players should not expect enhancement in intermittent-sprint performance from NaHCO3 supplementation. These findings are contrary to previous NaHCO3 studies on simulated team-sport performance, but this investigation is unique in that it examined highly-trained athletes performing sport-specific tasks. In conclusion, the findings of this thesis add to the existing literature on the applied physiology of women's water polo. It is hoped that the knowledge gained from these findings will lead to more appropriate conditioning, testing and selection outcomes.
19

Optimiser les réponses physiologique et affective à l'exercice chez les personnes âgée et obèse / Optimizing physiological and affective responses to exercise in older and obese persons

Borowik, Anna 22 December 2017 (has links)
L’activité physique (AP) induit des nombreux bénéfices sur la santé. Cependant, le niveau d’inactivité reste important : 42% des Français ne pratiquent aucune AP de loisir. Plusieurs facteurs déterminent l’engagement durable dans l’AP. Cette thèse a pour objectif d’évaluer certains des facteurs susceptibles d’améliorer cet engagement : modalité d’exercice, réponse affective à l’exercice, motivation pour l’AP, et d’optimiser les réponses physiologique et affective à l’exercice.L’oxydation des lipides joue un rôle important dans la prévention et le traitement de certaines pathologies cardio-métaboliques. Des travaux récents montrent l’intérêt potentiel d’un programme d’exercice intermittent intense (EII) sur la diminution de la masse grasse. Nous avons tenté d’optimiser l’oxydation lipidique survenant au cours d’un exercice combiné (COMB : 10-min d’EII + 35-min d’exercice d’intensité modérée continu, EIMC) comparé à une séance d’EIMC prolongé. Ce protocole original induit une oxydation lipidique plus importante (1,5 fois) dans la phase de 35-min d’EIMC au cours de COMB que celle obtenue au cours d’un EIMC prolongé isocalorique. Cette étude montre l’intérêt de l’EII pour augmenter le métabolisme lipidique.La modalité d’exercice ainsi que la réponse affective à l’exercice sont importants pour l’engagement durable dans l’AP. L’étape suivante de ce travail de thèse a consisté donc à évaluer la réponse affective aux différentes modalités d’exercice aigus (EIMC vs EII, avec pic d’intensité au début, au milieu et à la fin, avec ou sans soutien de l’autonomie) chez les individus en surpoids/obèses et chez la personne âgée. Ces populations ont été choisies car elles sont peu enclines à faire de l’AP régulière, alors qu’elle est importante pour eux. Les résultats de ces études montrent que la réponse affective diminue progressivement au cours de l’exercice dans toutes les conditions. Cependant, cette diminution est moins importante dans les conditions avec soutien de l’autonomie (chez la personne âgée et chez les sujets sains) indiquant l’importance de ce facteur. D’autre part, le moment auquel le pic d’intensité apparait détermine la réponse affective qui est plus négative quand la séance se termine avec l’exercice le plus intense.Après avoir évalué les effets de l’exercice aigu sur la réponse affective à l’exercice chez la personne en surpoids/obèse, nous nous sommes intéressés aux effets de l’entraînement sur la condition physique, les variables cardio-métaboliques, la réponse affective et la motivation. Ainsi, la dernière partie de travail de recherche a consisté alors à examiner les effets à court et long terme de l’entrainement (exercice intermittent intense sans : EII, et avec soutien de l’autonomie : EII+SA vs EIMC et groupe contrôle). Les résultats montrent qu’après les deux modalités d’entrainement intermittent intense la condition physique était améliorée après 24 séances. Ce type d’exercice influence positivement la composition corporelle. Cependant, les indicateurs de santé cardio-métabolique n’ont pas été modifiés. L’EII induit un moindre niveau de difficulté perçu de l’effort quand il est combiné avec un soutien de l’autonomie.Cette thèse montre que certaines modalités d’exercice (EII et/ou exercice qui se termine avec une intensité moins importante) ainsi que le soutien de l’autonomie favorisent une réponse affective positive qui pourrait influencer un engagement durable à l’AP. Ceci reste cependant à être démontré. / Regular physical activity (PA) induces many health benefits. However, the level of inactivity remains high: in France 42% of the population do not engage in any sport or leisure time PA. Many factors are responsible for the long-term involvement in PA. The main objective of this thesis was to evaluate some of those factors (exercise modality, affective response to exercise, PA motivation) and to optimize the physiological and affective responses to exercise.Lipid oxidation plays an important role in the prevention and in the treatment of metabolic diseases. Recent studies show the effectiveness of high intensity intermittent exercise (HIIE) on body fat. In this study we sought to optimize the lipid oxidation during a combined exercise (COMB: 10-min HIIE + 35-min prolonged moderate intensity continuous exercise, MICE). The results of this innovative study shows that fat oxidation can be increased (1.5 times) during 35-min MICE of COMB compared to the same period of a prolonged MICE if it’s performed after high intensity interval exercise (HIIE) vs an isocaloric MICE alone. This study shows the importance of HIIE to increase fat metabolism.The type of exercise, as well as affective response to exercise are important in order to increase regular PA participation. In the next part of this thesis, we assessed the affective response to different exercise modalities (MICE vs HIIE, peak of intensity at the beginning, in the middle or at the end of exercise, exercise with or without autonomy support) in overweight/obese subjects and in older adults. These populations were chosen because of their low PA participation level despite of its importance for health. The results show the decrease of affective response in each type of exercise. However, this decrease was lower in all autonomy supportive conditions (in older adults and in healthy subjects) showing the importance of this factor. In addition, the peak intensity time influenced the affective response: more negative feelings were observed when the session ended with the peak of intensity.After examining the effects of acute exercise sessions on affective response in overweight/obese subjects, we focused on the effects of exercise training on physical fitness, cardio metabolic health, affective response and motivation. Hence, in the last part of this thesis we examined the short and long-term effects of HIIE training vs MICE and control group. The main results showed the increase in physical fitness after two high intensity conditions. In addition, HIIE improved body composition. However, the cardio metabolic health variables remained unchanged after 24 sessions. In addition, HIIE induced a lower level of perceived exertion during exercise when it was combined with autonomy support.The results of this thesis show that some of exercise modalities (HIIE and/or exercise that ends with lower intensity) and autonomy support promote more positive affective response and can potentially influence the long term PA engagement. But the latter needs to be demonstrated.
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Modalités d'exercice et de récupération : approche cardiovasculaire et performance / Exercises modalities and recovery strategies : cardiovascular aspects and performance

Ménétrier, 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. (...)

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