• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 6
  • 5
  • 2
  • 1
  • Tagged with
  • 17
  • 17
  • 9
  • 6
  • 6
  • 4
  • 3
  • 3
  • 3
  • 3
  • 3
  • 3
  • 3
  • 2
  • 2
  • 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.
1

The Ventilatory Threshold and Maximal Steady-State Exercise in Patients with Coronary Artery Disease

Melvin, William Stacy 13 May 1998 (has links)
BACKGROUND: Previous research has shown that the ventilatory threshold (VT) correlates highly with onset of lactate accumulation and maximal steady-state exercise (MSS) level. Also, studies have shown the VT is useful in prescribing exercise for cardiac patients in that it gives an exercise intensity at which the patient is metabolically stable. METHODS: The purpose of this study was to determine if a MSS response could be achieved at an exercise intensity corresponding to the VT for patients with CAD. A group of 31 patients with CAD performed a maximal effort treadmill exercise test in which respiratory gas exchange was measured. The VT was determined using the V-slope method of computer regression analysis of the plot of carbon dioxide production versus oxygen consumption. Subjects then performed a constant load treadmill test a speed and grade that corresponded to the VT. Heart rate (HR), systolic blood pressure (SBP), and rating of perceived exertion (RPE) evaluated for steady-state responses. If subjects showed a steady-state response in two of these three parameters they were scored as having achieved a maximal steady-state (MSS+) response; those not meeting this standard were scored as failing to achieve maximal steady-state (MSS-) response. Subjects were analyzed as an entire group (N=31), as well as analyzed in subsets according to history of myocardial infarction (MI+, N=20; MI-, N=11) and administration of beta-blocker medications (BB+, N=16; BB-, N=15). RESULTS: Overall, subjects demonstrated significantly more MSS+ responses than MSS- responses (80% Vs 20%, P<0.05). Analysis of the subgroup data showed that it was the patient s with a history of MI (MI+ =85%, P<0.05) and those not receiving beta-blocker medications (BB- = 93%, P<0.05) who had significantly greater proportions of subject achieving MSS+ responses in the fixed load exercise condition. Conversely patient in the MI- (73 %, P < 0.05) and BB (69% P < 0.05) groups showed no significant differences in the number of MSS+ and MSS- responses. CONCLUSIONS: The VT, as measured during ramp exercise testing on the treadmill, provided a basis for establishing a maximal steady-state load in terms of cardiovascular and perceptual variables for 80% of the patients in the CAD study group. The measurements of HR, SBP, and RPE are easily obtained in a clinical setting and thus enable the VT to be used in bringing about a more efficacious exercise prescription. The validity of this method may be questioned, however, for patient with out a history of MI and for those receiving beta-blocker medications. / Master of Science
2

Cinétique des réponses cardiorespiratoires et métaboliques lors d'un exercice incrémentiel maximal chez l'homme / Kinetic of cardiorespiratory and metabolic responses during maximal incremental exercise in human

Gravier, Gilles 18 November 2013 (has links)
Notre travail de thèse avait pour buts d’explorer les mécanismes de contrôle de la fonction respiratoire au cours de l’exercice incrémentiel maximal mais également de corréler les évènements biochimiques associés à l’exercice progressif aux modifications de l’électromyogramme des muscles participant à l’effort. Les résultats de nos trois études ont montré : 1) que la baisse de PO2, intervenant pendant les premiers paliers d’un exercice incrémentiel maximal, était bien dépendante d’une défaillance de la commande centrale de la réponse ventilatoire. 2) que le pattern ventilatoire durant la période située entre le seuil ventilatoire (VTh) et le 2ème seuil (RCP) lors d’un exercice incrémentiel, pouvait évoluer selon deux modalités différentes, l’une caractérisée essentiellement par une augmentation de VT (un tiers des sujets) et l’autre déterminée majoritairement par une augmentation de FR. L’hypothèse d’une différence interindividuelle du gain du réflexe de Hering-Breuer peut être évoquée pour expliquer ces différents modes ventilatoires pendant l’exercice ; 3) qu’il est mesuré une augmentation de la concentration plasmatique de l’IMA (marqueur du stress oxydatif), corrélée à la consommation de RAA (antioxydant endogène), durant la phase la plus intense de l’exercice incrémentiel. L’adaptation de la commande motrice via le mécanisme d’épargne musculaire (« muscle wisdom ») n’intervient que chez les sujets qui développent un stress oxydatif. Ainsi, la variabilité interindividuelle mesurée dans l’amplitude du stress oxydatif, à niveau d’exercice comparable, affecte la capacité des sujets à lutter contre la fatigue musculaire. / The aim of our PhD work was to explore, in healthy humans, the control mechanisms of the respiratory function during a maximal incremental exercise and also to correlate the changes in the motor control of working muscles to the changes in exercise-induced blood signals. The results of our three studies showed:1) The occurrence of a PO2 fall during the first steps of the incremental exercise, associated with a modest PCO2 increase, strongly suggests a non-adaptation of the central command to the oxygen demand and CO2 washout;2) Two opposite changes in the ventilatory pattern were observed between the ventilatory threshold (VTh) and the respiratory compensation point (RCP); one third of the subjects tends to recruit predominantly VT and the others the breathing frequency. The hypothesis of an inter-individual difference in the strength of the Hering-Breuer reflex seems to be the more consistent explanation. 3) The plasma concentration of IMA, a marker of the oxidative stress, increased at the highest levels of incremental exercise and was correlated to the consumption of endogenous antioxidant (RAA). Because we observed that the adaptive motor response to cycling (leftward shift of the EMG spectrum) closely depends on the importance of the oxidative stress response, we hypothesized that all the healthy subjects do not have the same chances to be protected against muscle fatigue.
3

Associação do polimorfismo da ECA e variáveis fisiológicas determinantes da aptidão aeróbia / Association of the ACE polymorphism and physiological variables correlated with aerobic fitness

Silva, Salomão Bueno de Camargo 13 March 2015 (has links)
O consumo máximo de oxigênio (VO2máx), o limiar ventilatório (LV), ponto de compensação respiratória (PCR) e a economia de corrida (EC) são importantes variáveis fisiológicas associadas com a aptidão aeróbia em corrida. Acredita-se que o polimorfismo da enzima conversora de angiotensina (ECA) possa estar influenciando nos valores dessas variáveis. Contudo, essa relação causal não tem sido amplamente estudada durante a corrida. Dessa forma, o objetivo do presente trabalho foi investigar a associação entre os genótipos da ECA e o VO2máx, LV, PCR e EC mensuradas durante a corrida em esteira. Cento e cinquenta (n = 150) voluntários fisicamente ativos realizaram os seguintes testes: a) teste incremental máximo para determinação do VO2máx, LV e PCR; b) dois testes de velocidade constante (10 km/h e 12 km/h) em esteira para determinação da EC. Os genótipos apresentaram a frequência de: II = 21% ; ID = 52% e DD = 27%. Os resultados apresentaram uma tendência dos indivíduos com o genótipo II apresentarem maiores valores do VO2máx (p = 0.08), bem como a análise do efeito prático apresentou um possível efeito benéfico desse genótipo. No entanto, não foi constatada diferença entre os valores do LV, PCR, e EC entre os indivíduos. Esses resultados sugerem que o genótipo II da ECA pode estar influenciando nos valores da variável máxima relacionada com o consumo de oxigênio / The maximal oxygen uptake (VO2máx), ventilatory threshold (VT), respiratory compensation point (RCP), and running economy (RE) are important variables associated with running aerobic fitness. However, the influence of Angiotensin Converting Enzyme (ACE) polymorphism on these variables determined in running has not been largely investigated. Therefore, the present study aimed to investigate the relationship between ACE genotypes and maximal oxygen uptake, respiratory compensation point, and running economy measured in running. One hundred and fifty (n = 150) physically active young men performed the following tests: a) a maximal incremental treadmill test to determine VO2máx and RCP, b) two constant-speed running test (10 km.h-1 and 12 km.h-1) to determine the RE. The genotype frequency were II = 21 %; ID = 52 %; DD = 27 %. There were a likely beneficial effect and a tendency for the participants with ACE II genotype to have higher VO2max values than DD or ID genotypes (p = 0.08) and the smallest worthwhile effects show a beneficial effect. There were not associations between the genotypes for RCP and RE. These findings suggest that II ACE genotype would influence in maximal variable correlated with oxygen consumption
4

Submaximal Exercise Capacity is Associated with Moderate-to-Vigorous Physical Activity in Children with Complex Congenital Heart Disease

Kung, Tyler 02 May 2019 (has links)
Background: Children with complex congenital heart disease (CHD) are exposed to cyanosis from birth until their surgical repair and are often not expected to participate in physical activities to the same extent as healthy peers because of a limited maximal exercise capacity (V̇O2max). Despite limitations in V̇O2max, these children may still have the capacity to perform most daily physical activity because it requires only a submaximal effort. The purpose of this research was to examine the relationships between submaximal exercise capacity, daily physical activity and cyanosis exposure, in children with complex CHD. Methods: Children with a single functioning ventricle (Fontan), tetralogy of Fallot or transposition of the great arteries, 10 to 17 years old were deemed eligible. The Bruce treadmill protocol with breath-by-breath analysis of oxygen consumption was used to assess submaximal exercise capacity. Five measures of submaximal exercise capacity were evaluated: energy consumption (V̇O2) at the ventilatory threshold, V̇O2 at a heart rate of 130 beats per minute (bpm), metabolic equivalents (METs) at ventilatory threshold, METs at 130 bpm and heart rate at stage 1 of the Bruce protocol. Moderate-to vigorous physical activity (MVPA) was measured (Actical accelerometer with 15 second epochs) for 7 consecutive days. Exposure to cyanosis was calculated by subtracting the child’s date of birth from the date of surgical repair. Results: Participants were children with a Fontan single ventricle (n=5), tetralogy of Fallot (n=4) or transposition of the great arteries (n=7). Daily physical activity was positively associated with V̇O2 at ventilatory threshold (r = 0.78, n = 16, p = < 0.01) and V̇O2 at a heart rate of 130 bpm (r = 0.61, n = 16, p = 0.01). Children who did more than 60 minutes of physical activity per day (n=4) achieved significantly higher energy expenditure before reaching ventilatory threshold, (95% CI of the difference [8.23, 24.85], t(14) = 4.27, p = < 0.01) and at a heart rate of 130 bpm (95% CI of the difference [1.61, 14.33], t(14) = 2.69, p = 0.02). Lastly, V̇O2 at ventilatory threshold was negatively associated with days spent in cyanosis (r = .55, n = 16, p = 0.03), Conclusion: Higher V̇O2 at ventilatory threshold and V̇O2 at a heart rate of 130 bpm was associated with more daily minutes spent in moderate-to-vigorous physical activity. These results suggest that children who meet the recommended 60 minutes of MVPA would have a higher submaximal exercise capacity (V̇O2 at ventilatory threshold or a heart rate of 130 bpm), than children who did not meet the MVPA guidelines. Lastly, children who were exposed to cyanosis for a longer period of time had a lower submaximal V̇O2 at ventilatory threshold, than children who were exposed to cyanosis for a shorter period of time.
5

Associação do polimorfismo da ECA e variáveis fisiológicas determinantes da aptidão aeróbia / Association of the ACE polymorphism and physiological variables correlated with aerobic fitness

Salomão Bueno de Camargo Silva 13 March 2015 (has links)
O consumo máximo de oxigênio (VO2máx), o limiar ventilatório (LV), ponto de compensação respiratória (PCR) e a economia de corrida (EC) são importantes variáveis fisiológicas associadas com a aptidão aeróbia em corrida. Acredita-se que o polimorfismo da enzima conversora de angiotensina (ECA) possa estar influenciando nos valores dessas variáveis. Contudo, essa relação causal não tem sido amplamente estudada durante a corrida. Dessa forma, o objetivo do presente trabalho foi investigar a associação entre os genótipos da ECA e o VO2máx, LV, PCR e EC mensuradas durante a corrida em esteira. Cento e cinquenta (n = 150) voluntários fisicamente ativos realizaram os seguintes testes: a) teste incremental máximo para determinação do VO2máx, LV e PCR; b) dois testes de velocidade constante (10 km/h e 12 km/h) em esteira para determinação da EC. Os genótipos apresentaram a frequência de: II = 21% ; ID = 52% e DD = 27%. Os resultados apresentaram uma tendência dos indivíduos com o genótipo II apresentarem maiores valores do VO2máx (p = 0.08), bem como a análise do efeito prático apresentou um possível efeito benéfico desse genótipo. No entanto, não foi constatada diferença entre os valores do LV, PCR, e EC entre os indivíduos. Esses resultados sugerem que o genótipo II da ECA pode estar influenciando nos valores da variável máxima relacionada com o consumo de oxigênio / The maximal oxygen uptake (VO2máx), ventilatory threshold (VT), respiratory compensation point (RCP), and running economy (RE) are important variables associated with running aerobic fitness. However, the influence of Angiotensin Converting Enzyme (ACE) polymorphism on these variables determined in running has not been largely investigated. Therefore, the present study aimed to investigate the relationship between ACE genotypes and maximal oxygen uptake, respiratory compensation point, and running economy measured in running. One hundred and fifty (n = 150) physically active young men performed the following tests: a) a maximal incremental treadmill test to determine VO2máx and RCP, b) two constant-speed running test (10 km.h-1 and 12 km.h-1) to determine the RE. The genotype frequency were II = 21 %; ID = 52 %; DD = 27 %. There were a likely beneficial effect and a tendency for the participants with ACE II genotype to have higher VO2max values than DD or ID genotypes (p = 0.08) and the smallest worthwhile effects show a beneficial effect. There were not associations between the genotypes for RCP and RE. These findings suggest that II ACE genotype would influence in maximal variable correlated with oxygen consumption
6

Capacités cardiorespiratoires de femmes atteintes de fibromyalgie évaluées selon un protocole, évaluation réévaluation / Cardiorespiratory fitness of women with fibromyalgia evaluated using an evaluation re-evaluation protocol

Bouvrette, Lucie January 2017 (has links)
Les études sur les capacités cardiorespiratoires de femmes atteintes de fibromyalgie (FM) présentent des résultats contradictoires. De plus, aucune étude n’a évalué les capacités à reproduire les mesures physiologiques cardiorespiratoires de cette population, 24 heures suivant un test d’effort maximal. Objectifs : Les objectifs de cette étude étaient les suivants: 1) de décrire la capacité cardiorespiratoire de femmes atteintes de FM et 2) de décrire leurs capacités à reproduire les mesures physiologiques cardiorespiratoires 24 heures suivant une épreuve d’effort cardiorespiratoire maximal. Méthodes : Douze femmes FM ont été soumises à deux épreuves d’effort cardiorespiratoire maximal (T1 et T2) sur tapis roulant (protocole BSU/Bruce ramp) à 24 heures d’intervalle, jusqu’à épuisement. La collecte des échanges gazeux et ECG ont été faites de façon continue tout au long des deux tests. Le lactate sanguin, la pression artérielle, l’intensité de la douleur et la perception de la difficulté à l’effort ont également été évalués. Le Questionnaire révisé sur l’impact de la fibromyalgie (QRIF), l’Échelle de kinésiophobie de Tampa, version canadienne-française (EKT-CF), et le questionnaire international sur le niveau d’activité physique, version canadienne-française (IPAQ) ont été utilisés afin de mieux décrire les caractéristiques des participantes. Des procédures statistiques non paramétriques ont été utilisées pour les besoins d’analyses statistiques. Résultats : En comparant les résultats du volume d'oxygène crête (VO2crête) obtenus au T1 aux valeurs normatives, 75% des participantes se situaient sous la catégorie “Passable”, dont 25% sous le seuil de la catégorie “Très pauvre”. Toutefois, en considérant le niveau de sévérité de la FM et comparant les participantes légèrement et modérément affectées au T1 et T2, les résultats ont démontré une différence significative de la VO2crête au T2 (30,4 ± 3,3 vs 22,9 ± 4,7 ml O2·min−1·kg−1) et de la VO2 au seuil anaérobie ventilatoire (VO2SAV) au T1 (24,0 ± 4,0 vs 18,5 ± 4,4 ml O2·min−1·kg−1) et T2 (24,9 ± 3,2 vs 18,7 ± 4,5 ml O2·min−1·kg−1). Finalement, aucune différence significative au niveau de la VO2crête (25,5 ± 5,3 vs. 26,5 ± 5,3 ml O2·min−1·kg−1, p > 0,05) et de la VO2SAV (21,2 ± 4,8 vs. 21,7 ± 4,8 ml O2·min−1·kg−1, p > 0,05) n’a été observée entre T1 et T2. Conclusion : Soixante-quinze pour cent des participantes avaient une capacité cardiorespiratoire inférieure à celle de la population générale. De plus, les capacités cardiorespiratoires des participantes semblent être affectées par le niveau de sévérité de la FM. Finalement, les résultats de cette étude ne démontrant pas de différence significative des capacités cardiorespiratoires entre T1 et T2, suggèrent qu’il n’y a pas de difficulté à reproduire les mesures physiologiques 24 heures suivant le premier test d’épreuve maximale. / Abstract: Studies on cardiorespiratory fitness (CRF) among women with fibromyalgia (FM) has been documented with some contradictory results. Furthermore, no research has looked at the capacity to reproduce the cardiorespiratory physiology measurements 24 hours following a maximal CRF test, in FM patients. Objectives: The objective of this study was twofold: 1) to describe the cardiorespiratory fitness of women with fibromyalgia (FM); and 2) to describe the reproducibility of cardiorespiratory physiological parameters 24 hours following a maximal exercise test. Method: Twelve FM women underwent two maximal exercise tests (T1 and T2) on a treadmill (BSU/Bruce ramp protocol) 24 hours apart, until volitional exhaustion. Gas exchange and ECG were continuously monitored during both tests. Blood lactate, blood pressure, pain intensity and rate of perceived exertion, were also assessed. The Revised Fibromyalgia Impact Questionnaire (FIQR), the Tampa Scale of Kinesiophobia (TSK-CF) and the International Physical Activity Questionnaire (IPAQ) were used to further characterize the participants. Non-parametric statistical procedures were used for statistical analysis. Results: When comparing the peak oxygen uptake (VO2peak) results to normative values at T1, 75% of the participants were below the “Fair” category, of which 25% were below the “Very Poor” category. However, when taking into consideration the FM severity level and comparing mildly to moderately affected participants at T1 and T2, the results showed a significant difference in VO2peak at T2 (30.4 ± 3.3 vs 22.9 ± 4.7 ml O2·min−1·kg−1) and in VO2 at ventilatory anaerobic threshold (VO2VAT) at T1 (24.0 ± 4.0 vs 18.5 ± 4.4 ml O2·min−1·kg−1) and T2 (24.9 ± 3.2 vs 18.7 ± 4.5 ml O2·min−1·kg−1). Finally, no significant differences in VO2peak (25.5 ± 5.3 vs. 26.5 ± 5.3 ml O2·min−1·kg−1, p > 0.05) and VO2VAT (21.2 ± 4.8 vs. 21.7 ± 4.8 ml O2·min−1·kg−1, p > 0.05) were found between T1 & T2. Conclusion: Seventy-five percent of the participants had a cardiorespiratory fitness level lower than the general population. Furthermore, the cardiorespiratory capacities of the participants seemed to be affected by their FM severity level. Finally, the results of this study showed no significant difference in cardiorespiratory fitness between T1 and T2, therefore indicating no cardiorespiratory difficulty to reproduce the physiological measurements 24 hours following a maximal exercise test.
7

EFFECTS OF CURCUMIN AND FENUGREEK SOLUBLE FIBER SUPPLEMENTS ON SUBMAXIMAL AND MAXIMAL AEROBIC PERFORMANCE INDICES IN UNTRAINED COLLEGE-AGED SUBJECTS

Goh Zhong Sheng, Jensen 01 January 2019 (has links)
Submaximal exercise performance is, in part, limited by the accumulation of metabolic byproducts and energy system capacities. Curcumin and the combination of curcumin and fenugreek soluble fiber (CurQfen®) have been shown to increase endogenous antioxidants and metabolic byproduct clearance as well as reduce inflammation and lipid peroxidation, and therefore, may enhance submaximal aerobic thresholds. In addition, there is evidence that the galactomannan component of fenugreek, used to enhance bioavailability of curcumin, may also have potential physiological effects related to the up regulation of free fatty acid oxidation Therefore, the purpose of this study was to examine the effects of curcumin and fenugreek soluble fiber supplementation on the ventilatory threshold (VT), respiratory compensation point (RCP), maximal oxygen consumption (O2 peak), and time to exhaustion (Tlim)derived from a graded exercise test (GXT). Forty-five untrained, college-aged, male (n = 24) and female (n = 21) subjects (mean age ± SD: 21.2 ± 2.5 yr) were randomly assigned to one of three supplementation groups; placebo (PLA, n=13), 500 mg·day-1 CurQfen® (CUR, n=14), or 300 mg·day-1 fenugreek soluble fiber (FEN, n=18). All of the subjects completed a maximal GXT on a cycle ergometer to determine the VT, RCP, O2 peak, and Tlim before (PRE) and after (POST) 28 days of daily supplementation. The VT and RCP were determined from the V-slope method for the ventilation (E)vs. O2 and E vs. CO2, respectively. Separate, one-way ANCOVAs were used to examine the between group differences for adjusted POST VT, RCP, O2 peak, and Tlim values, with the respective PRE test value as the covariate. The adjusted POST VT-O2 for the CUR (mean ± SD= 1.593 ± 0.157 L·min-1) and FEN (1.597 ± 0.157L·min-1) groups were greater than (p= 0.04 and p= 0.03, respectively) the PLA (1.465 ± 0.155L·min-1) group, but the FEN and CUR groups were not different (p = 0.94). The one-way ANCOVAs for RCP (F = 3.177, p = 0.052), O2 peak (F = 0.613, p = 0.547), and Tlim (F = 0.654, p = 0.525) indicated there were no significant differences among groups. These findings suggested that CurQfen® and/or fenugreek soluble fiber may improve submaximal, but not maximal, aerobic performance indices in untrained subjects.
8

Contribution to the study of the limitation of aerobic exercise capacity in obese patients: impact of bariatric surgery and contribution of the pulmonary hemodynamic

Zhou, Na 06 October 2021 (has links) (PDF)
Obesity, as an inflammatory state, can cause multi-organ disease, which often manifested in poor physical fitness involving the respiratory, cardio-vascular and muscles limitation. Bariatric surgery has become an important treatment option in severe obesity. The remarkably and rapid surgical weight loss, the obese patient gave feedback that they can walk further, but feels “no energy in his feet to speed up, when they need to run a few steps to catch the bus”. Had her physical condition already improved? Does weight loss after surgery equal improved physical condition? How does the heart, lungs, and muscles response to exercise? In order to search for the answer, we reviewed the previous relevant research, regarding the changes of postoperative aerobic capacity and we tried to discuss from a holistic perspective our observations.The thesis is divided into two modules including three studies.The first module including study 1 and 2, which are designed to identifies the determinants of the aerobic exercise capacity following weight loss reduced by bariatric surgery. We turn the daily problems feedback from obese patients who underwent bariatric surgery into three scientific questions:- What is the impact of adipose tissue on determinants of aerobic exercise capacity?- What is the impact of bariatric surgery on determinants of aerobic exercise capacity?- Do obese patients return to normal after bariatric surgery?Based on the limited knowledge and experience of predecessors about how obesity influences exercise pulmonary hemodynamics, the second module including study 3, which are designed to further analysed the right ventricle - pulmonary circulation during exercise and to answer the following question:- how does obesity affect right ventricular, pulmonary circulation and gas exchange adaptation during exercise?To answer these questions, we recruited 29 obese subjects and paired to age-, sex- and height- matched 29 healthy controls. A subgroup of thirteen patients who underwent bariatric surgery were retested 6 months after surgery and compared with theirs controls. Then, we comprehensive analysed the results of following tests: blood test, clinical assessment, body composition analysis, muscle strength measurements, pulmonary function (spirometry and diffusion capacity), exercise stress echocardiography, questionnaires and exercise capacity tests.The results of study 1 shown that, obese subjects had lower weekly moderate-to-vigorous physical activity (MVPA) and SF-36 scores, maximal workload and peak oxygen consumption (VO2peak) relative to body weight, but similar absolute VO2peak. Bariatric surgery resulted in -22% body weight,vi- 34% fat mass, -40% visceral adipose tissue and -12% lean mass (LM) changes. Absolute handgrip, quadriceps or respiratory muscle strength remained unaffected but accompanied by an increase in MVPA, SF-36 scores and quadriceps strength relative to LM. No changes in absolute VO2peak were observed after surgery but the ventilatory threshold was decreased.The results of study 2 shown that, obese subject had lower resting lung diffusion capacity with mainly a reduction in pulmonary capillary blood volume and alveolar volume (VA). After bariatric surgery, lung diffusion capacity for nitric oxide, VA and membrane diffusion capacity have improved to varying degrees.The results of study 3 shown that, there was no difference in pulmonary circulation at rest between the two groups, but the pulmonary vascular resistance index (PVRi) was higher with lower heart rate, cardiac output, cardiac index (CI) and mean pulmonary arterial pressure (mPAP) in obese subjects at peak exercise. After being normalized by CI at a common maximum exercise level, the PVRi was still higher, but the difference of mPAP disappeared and manifested a higher mPAP and mPAP/CI slope. The tricuspid annular plane systolic excursion /systolic PAP was lower at rest and at a common maximum exercise level when normalized by CI.In summary, obesity was associated to low vigorous daily physical activity levels, SF-36 physical and mental component scores, higher muscle mass but lower strength/LM ratio and aerobic capacity. Lower spirometry and lung diffusion capacity with mainly reduction in Vc and VA may also limit maximum aerobic exercise capacity. At rest, the pulmonary hemodynamic is preserved, but with a weakness of right ventricular-arterial coupling. At exercise, obesity has a modest, but observable impact on the pulmonary circulation and right ventricular adaptation at exercise, with unexhausted chronotropic reserve and normal chemo-sensibility.Bariatric surgery shows beneficial effects on fat mass loss, metabolic parameters, daily physical activities, SF-36 scores, lung function and stimulated the chronotropic response. However, aerobic capacity is not improved and is associated with a reduced LM and ventilatory threshold potentially triggering hyperventilation. / Doctorat en Sciences de la motricité / info:eu-repo/semantics/nonPublished
9

Comparação ente indicadores do teste ergoespirométrico e qualidade de vida entre idosos não-treinados e treinados / Comparison between indicators of cardiopulmonary exercise test and quality of life among trained and untrained elderly

Cardoso, Aretusa 12 May 2011 (has links)
O objetivo deste estudo foi comparar indicadores ergoespirométricos entre um grupo de idosos não-treinados (GINT) e o grupo de idosos treinados (GIT) em corridas de longa distância e a associação com a qualidade de vida. Uma amostra de 46 indivíduos idosos, dos quais 27 (idade = 73,1 ± 4,3 anos) estavam engajados em treinamento para corridas de longa distância e 19 (idade = 73,5 ± 6,4 anos) idosos que não praticavam exercício físico regular. Todos foram submetidos à avaliação cardiorrespiratória e metabólica, utilizando se analisador metabólico de gases (CPX/D, MedGraphics®, EUA) acoplado a eletrocardiógrafo (HeartWere®, 6.4, BRA), ambos os sistemas computadorizados. A determinação da capacidade física máxima foi verificada em esteira rolante (Inbramed®, ATL10200, BRA) utilizando se protocolo escalonado contínuo (1,2 km.h-1 a cada dois minutos) e inclinação fixa de 1%. Os seguintes resultados verificados foram: No segundo limiar ventilatório (VT2) [GINT vs. GIT]: FC (bpm) [69,4 ± 9,9 vs. 65,4 ± 6,8; p <0,05]; RQ [1,03 ± 0,03 vs.1,01 ± 0,03; p <0,05]; PO2 (mL/bpm) [11,3 ± 2,4 vs.14.4 ± 2,8; p <0,05]. No pico do esforço: VO2max (mL/kg/min) [27 ± 5,4 vs. 39,3 ± 5,6; p <0,05], TT (min) [9,6 ± 2,9 vs. 16,4 ± 2,7; p <0,05] e velocidade de corrida (km.h-1) [9,7 ± 2,5 vs. 13,3 ± 2,5; p <0,05]. Para medir a qualidade de vida foi utilizado o questionário WHOQOL. WHOQOL pontos [GINT vs. GIT: [70 ± 5 versus 71 ± 6] Avaliou-se o uso de medicamentos de diferentes grupos farmacológicos através de entrevistas e análise de pedidos médicos. Concluindo, a capacidade de desempenho cardiorrespiratório do GIT foi significativamente maior do que o GINT. No entanto, a qualidade de vida não foi diferente entre os dois grupos. Houve diferença na proporção de medicamentos utilizados entre os grupos. O GIT aparece com maior incidência no uso de Antiarrítmicos, Antiinflamatórios e Relaxantes Musculares. Ao contrário, o GINT apresentou maior uso de Hipoglicemiantes e Anti-Coagulantes. A maior utilização de antiinflamatórios e analgésicos pelo GIT pode ser devido ao fato de que os corredores têm maior prevalência de lesão muscular. Já a maior utilização de Hipoglicemiantes e Anti-Coagulantes pelo GINT, demonstra a falta de proteção cardiovascular pelo sedentarismo / The main purpose of this study was to compare ergoespirometric indicators among a group of elderly untrained (GEU) and a group of elderly old trained (GET) in long-distance race and the association with quality of life. Twenty seven (age = 73.1 ± 4.3 years) were engaged in training for distance running and 19 (age = 73.5 ± 6.4 years) older adults who did not practice regular physical exercise. All were underwent a cardiopulmonary exercise test evaluation. To this end we used a gas explorer (CPX/D, breathby breath Medgraphics®, Saint Paul, MN, USA) coupled to an electrocardiograph (HeartWere®, 6.4, BRA). Both systems were computerized. The determination of the maximum physical capacity was assessed on a treadmill (Inbramed ®, ATL-10200, BRA) using incremental protocol (1.2 km.h-1every two minutes) and a fixed inclination of 1%. The following results were observed: In second ventilatory threshold (VT2) [GEU vs. GET]: HR (bpm) [69.4 ± 9.9 vs. 65.4 ± 6.8; p <0.05], RQ [1.03 ± 0.03 vs.1.01 ± 0.03; p <0.05]; PO2 (mL/bpm) [11.3 ±2.4 vs.14.4 ± 2.8, p <0.05]. At peak effort: VO2max (mL/kg/min) [27 ± 5.4 vs. 39.3 ± 5.6; p <0.05], TT (min) [9.6 ± 2.9 vs. 16.4 ± 2.7; p <0.05] and running speed (km.h-1) [9.7 ± 2.5 vs. 13.3 ± 2.5; p <0.05]. To measure quality of life we used the WHOQOL. WHOQOL points [GEU vs. GET: [70 ± 5 vs. 71 ± 6] evaluated the use of drugs from different pharmacological groups through interviews and medical applications. In conclusion, the cardiorespiratory capacity of the GET was significantly higher than the GEU. However, the quality of life was not different between the two groups. Differences in the proportion of medicines used by the groups. GET appears with a higher incidence in antiarrhythmics, anti-inflammatory and muscle relaxants. Instead, the GEU showed greater use of hypoglycemic and anti-coagulants. The increased use of antiinflammatory and muscle relaxants effects by the GET may be due to the fact that runners have a higher prevalence of muscle damage. Instead, the increased use of hypoglycemic and anti-coagulants by GEU, demonstrates the lack of cardiovascular protection by physical inactivity
10

Correlação entre o ponto de compensação respiratoria e desempenho em corredores de rua / Correlation between respiratory compensation point and performance in runners

Lourenço, Thiago Fernando 07 February 2009 (has links)
Orientador: Luiz Eduardo Barreto Martins / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Educação Fisica / Made available in DSpace on 2018-08-14T08:00:32Z (GMT). No. of bitstreams: 1 Lourenco_ThiagoFernando_M.pdf: 1713436 bytes, checksum: d718517b4524a25dc81ced71623cc066 (MD5) Previous issue date: 2009 / Resumo: O consumo máximo de oxigênio (VO2max) é considerado medida padrão de potência aeróbica e desempenho físico, por integrar os sistemas nervoso, cardiopulmonar e metabólico e foi considerado fator determinante para o desempenho de corredores devido as boas correlações encontradas em corridas de 10 a 90 km. Além dele, parâmetros submáximos relacionados ao teste de esforço máximo como limiar ventilatório (LV) e ponto de compensação respiratória (PCR) são usados para a prescrição de intensidades de exercício. Durante a década de 80 inúmeros trabalhos sugeriram que a velocidade de corrida referente ao LV (vLV) seria um bom indicador da capacidade de realizar esforços de longa duração. No entanto, recentes achados relacionando a velocidade entre LV e PCR contradizem tais afirmações. Além disso, poucos trabalhos na literatura buscaram investigar a possível correlação entre a velocidade de corrida referente ao PCR (vPCR) e corrida de 10km. Já que a determinação das vLV, vPCR e vVO2max parecem ser importantes na determinação de desempenho e prescrição de treinamento, os protocolos de esforço máximo aplicados nessa população deveriam se aproximar das condições reais de treinamento e competições desses atletas, bem como determinar claramente tais parâmetros. No entanto, protocolos clássicos ainda são utilizados, devido à tradição e familiaridade dos avaliadores, sem a preocupação do embasamento metabólico e estatístico. Essa escassez de protocolos acaba por dificultar a aplicação prática dos dados obtidos e a determinação do desempenho de corredores. Nesse sentido, buscamos neste trabalho i) propor e verificar a reprodutibilidade de um protocolo incremental em esteira ergométrica específico para corredores e ii) investigar possível relação entre vPCR e desempenho na corrida de 10km (v10km) dessa população. Primeiramente, foram avaliados onze corredores amadores, os quais foram submetidos a quatro repetições do protocolo proposto: estágios de 25 segundos, com incrementos de 0.3 kmoh?1 na velocidade de corrida e inclinação fixa da esteira em 1%. Não encontramos diferenças significativas em nenhum parâmetro analisado no LV, PCR e VO2max (p>0.05). Todos os resultados mostraram alta reprodutibilidade (CV<9.1%) e valores de erro típico (TE) encontrados para vVT (TE = 0.62 km o h?1), vPCR (TE = 0.35 km o h-1) e vVO2max (TE = 0.43 km o h?1) indicaram alta sensibilidade e reprodutibilidade do protocolo. Posteriormente, vinte corredores realizaram uma simulação de prova de 10km em pista de atletismo e, após 72h, um teste de esforço máximo em esteira ergométrica para a determinação dos parâmetros máximos e submáximos. Valores de v10km foram significativamente superiores aos de vLV e inferiores aos de vVO2max (p>0.05). Nenhuma diferença significativa foi observada entre v10km e vPCR (p<0.05). Fortes correlações entre v10km e vLV (r = 0.92; R2 = 0.84) e vVO2max (r = 0.93; R2 = 0.86) foram encontradas. Sendo a maior delas observada entre vPCR e v10km (r = 0.96; R2 = 0.92). Esses resultados indicam que o protocolo de esforço máximo sugerido aqui é possivelmente capaz de avaliar pequenos efeitos do treinamento nos parâmetros máximos e submáximos, além mostrar a vPCR como um parâmetro interessante na predição de desempenho para corredores de 10km. / Abstract: The maximum oxygen uptake (VO2max) is considered a standard measure of aerobic capacity and physical performance for integrating the nervous systems, cardiopulmonary and metabolic and was considered a decisive factor for runners due good correlations found in run from 10 to 90 km. Besides him, sub maximal parameters related to the maximum effort test as ventilatory threshold (VT) and respiratory compensation point (RCP) are used for prescription of exercise intensities. During eighties, countless works suggested that the race speed regarding VT (sVT) would be good indicators of the capacity to accomplish long duration efforts. However, recent discoveries relating the speed between VT and RCP contradict such statements. Besides, few works in the literature looked for to investigate the possible correlation among the race speed regarding RCP (sRCP) and race of 10km. Since the determination of the sVT, sRCP and sVO2max seem to be important in the acting determination and training prescription, the protocols of maximum effort applied in runners would approximate of the real training conditions and those athletes' competitions, as well as to determine such parameters clearly. However, classic protocols are still used, due to the tradition and the appraisers' familiarity, without the concern of the metabolic and statistical concepts. That shortage of protocols used for runners hinders the practical application of obtained data and determination of their performance. In that sense, we looked for in this work i) to propose and verify the reproducibility of an incremental protocol in treadmill specific for runners and ii) investigate possible relationship between sRCP and the average running speed in a 10km race (s10km). Firstly, were appraised eleven amateur runners, which were submitted to four repetitions of proposed protocol: stage durations of 25 seconds, with increments of 0.3km·h-1 in the race speed and treadmill inclination stayed fixed in 1%. We didn't find significant differences in any parameter analyzed in VT, RCP and VO2max (p>0.05). All the results showed high reproducibility (CV <9.1%) and values of typical error (TE) found for sVT (TE = 0.62 km ·h-1), vPCR (TE = 0.35 km ·h-1) and sVO2max (TE = 0.43 km · h-1) indicated high protocol's sensibility and reproducibility. Later, nineteen runners accomplished a 10km race simulation in an outdoor track and, after 72 hours, a maximum effort test in a treadmill for the determination of the maximum and sub maximal parameters. v10km values were superiors significantly to the sVT and inferior to the vVO2max (p>0.05). No significant difference was observed between v10km and sRCP (p <0.05). Strong correlations between v10km and sVT (r = 0.92; R2 = 0.84) and vVO2max (r = 0.93; R2 = 0.86) were found. Being the largest observed between sRCP and v10km (r = 0.96; R2 = 0.92). Those results indicate that maximum effort protocol suggested here is possibly capable to evaluate small effects during the training process in the maximum and sub maximal parameters, beyond to show the sRCP as an interesting parameter in the prediction of runner's performance in 10km races. / Mestrado / Biodinamica do Movimento e Esporte / Mestre em Educação Física

Page generated in 0.5835 seconds