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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.
21

Limiar de fadiga neuromuscular determinado por diferentes periodos de analise do sinal eletromiografico / Neuromuscular fatigue threshold established by different analysis periods of electromyography signs

Fontes, Eduardo Bodnariuc, 1979- 02 August 2008 (has links)
Orientador: Antonio Carlos de Moraes / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Educação Fisica / Made available in DSpace on 2018-08-10T17:31:59Z (GMT). No. of bitstreams: 1 Fontes_EduardoBodnariuc_M.pdf: 546789 bytes, checksum: e5cf58e2e5bc2c9f182d7e783137819d (MD5) Previous issue date: 2008 / Resumo: LFNM estabelecido por diferentes períodos de análise do sinal eletromiográfico e comparar os mesmos com a Potência Crítica - PC em indivíduos saudáveis. A amostra foi composta por 17 voluntários saudáveis do sexo masculino (23,4 ± 5,2 anos, 73,6 ± 5,08 kg, 177,8 ± 7,0 cm). Para determinar o LFNM, cada sujeito realizou entre três e quatro cargas constantes no cicloergometro (modelo Corival 400, Quinton Inc, USA) até a exaustão voluntária, com cadência de 60 rpm. Utilizando um eletromiógrafo de 16 canais (MP150, Biopac Systems, Inc., USA), foram coletados sinais EMG do músculo Vasto Lateral. O LFNM foi calculado pelo modelo matemático proposto por (DEVRIES et al., 1982), no qual a taxa de aumento do sinal eletromiográfico atingido durante as cargas constantes é plotado em função das respectivas cargas, sendo o intercepto ¿y¿ do prolongamento desta reta considerado o LFNM. Tal procedimento foi reproduzido para cada um dos tempos de duração de análise, 30 segundos (T30s), um minuto (T1min), dois minutos (T2min) e tempo total (TTotal). PC foi determinada através do modelo hiperbólico. Utilizando a potência de LFNM encontrada por TTotal, foi verificado ainda a capacidade dos voluntários de permanecer em teste retangular de 30 min, sem evidência de fadiga neuromuscular. Foram encontradas diferenças significativas entre os períodos de análise para determinação de LFNM (ANOVA). Utilizando T30s a média alcançada foi 266,7 ± 23,1 W, com T1min ficou em 243,4 ± 16,2 W, para T2min obteve 232,6 ± 18,3 W, e utilizando TTotal a média foi de 217,2 ± 23,1 W, já para PC, foi encontrado valores médios de 177,9 ± 27,3 W. Foram encontradas diferenças estatisticamente significantes entre T30s e todos os outros períodos de análise, T1min, T2min e TTotal (p<0,01). O LFNM determinado com T1min, foi diferente estatisticamente também de TTotal (p<0,01). Todos os períodos de análise utilizados para determinar LFNM superestimaram estatisticamente PC (p<0,01). Foi encontrada correlação significativa apenas para TTotal e PC (R2 = 0,72). Durante o protocolo de carga retangular de 30 minutos, a média da exaustão ocorreu em 661,6 ± 303,9 segundos, apenas um dos voluntários completou os teste de 30 minutos. O nível de significância adotado para todas as análises foi de 5%. A partir dos resultados do presente estudo, é possível concluir que o tempo de análise influencia na determinação de LFNM, superestimando PC e a capacidade de adultos jovens em realizar exercícios de carga constante de 30 minutos em cicloergômetro / Abstract: The purpose of this study was to establish the Neuromuscular Fatigue Threshold - LFNM determinied by different analysis periods of electromyography sign and compare to the Critical Power - CP in healthy young men. 17 healthy men volunteers (23,4 ± 5,2 years, 73,6 ± 5,08 kg, 177,8 ± 7,0 cm) completed three or four constant loads tests on a cycling ergometer to establish LFNM (model Corival 400, Quinton Inc, USA) until exhaustion, and the pedal cadence was 60 rpm. Using an amplifier with 16 channels (MP150, Biopac Systems, Inc., USA), were collected EMG signs from Vastus Lateralis muscle from the dominant side. The LFNM were calculated by the mathematical model proposed by DeVries et al., (1982) where the LFNM was considered the y intercept of the regression line the EMG slopes from contant load tests plotted against its respective load. CP was calculated using the hyperbolic equation model. The LFNM procedure was done by each period of EMG analysis 30 seconds (T30s), one minute (T1min), two minutes (T2min) and total period (TTotal). Using LFNM established by TTotal, were verified the capacity of the volunteers to complete a 30 minutes constant load test, without neuromuscular fatigue. ANOVA found statistical differences between analysis periods. Using T30s, the mean found were 266,7 ± 23,1 W, with T1mn were 243,4 ± 16,2 W, for T2min were 232,6 ± 18,3 W, and with TTotal, the mean were 217,2 ± 23,1 W, however, for CP were found 177,9 ± 27,3 W. Were found statistical differences between T30s and all the others analysis periods, T1min, T2min and Total (p<0,01). The LFNM established by T1min were also different from TTotal (p<0,01). All the analysis periods overestimated PC (p<0,01). Were found significant correlation between only PC and TTotal (R2 = 0,72). During the 30 minutes constant load test completed, the exhaustion mean time were 661,6 ± 303,9 seconds, and only one volunteer completed all the 30 minutes. The significance level adopted for all analysis was 5%. According to the results of this study, it is possible to conclude that the analysis periods influences the determination of LFNM, and it overestimates CP and the capacity of the healthy adults to complete a 30 minutes constant load test in cycling ergometer / Mestrado / Ciencia do Desporto / Mestre em Educação Física
22

Determinação do limiar de anaerobiose ventilatório no exercício físico dinâmico em indivíduos sadios: comparação entre métodos obtidos por análise visual e modelos matemáticos. / Determination of ventilatory anaerobic threshold in dynamic exercise of healthy subjects: comparison among methods obtained by visual analyses and mathematical models.

Julio César Crescencio 24 October 2002 (has links)
Os avanços tecnológicos ocorridos na última década trouxeram enormes benefícios, no sentido de possibilitar o uso de equipamentos computadorizados, que permitem a aquisição, processamento e armazenamento de um grande número de variáveis respiratórias e metabólicas em exercício físico, em tempo real e de ciclo a ciclo respiratório. Dentro deste novo cenário, o estudo realizado com esta nova geração de equipamentos, nas respectivas áreas de conhecimento, pôde ser direcionado, usando-se métodos matemáticos e estatísticos computadorizados, os quais possibilitam a aplicação de procedimentos automáticos e/ou semi-automáticos na solução de problemas específicos. É dentro deste contexto que se insere o presente estudo, que tem por objetivo comparar, em indivíduos sadios do sexo masculino, o limiar de anaerobiose ventilatório, durante o exercício físico dinâmico, usando-se métodos visuais gráficos e métodos baseados em modelos matemáticos, automáticos e semi-automáticos. Foram estudados 24 voluntários sadios do sexo masculino, com idade média de 33,8 ± 9,25 anos. Todos eles se submeteram a um ou dois testes de esforço físico dinâmico, segundo um protocolo contínuo do tipo rampa, na posição sentada, em cicloergômetro eletromagnético, acoplado a um sistema ergoespirométrico computadorizado (CPX/D – MedGraphics), que possibilita o cálculo de múltiplas variáveis cardiorrespiratórias, como: ventilação pulmonar (VE), produção de CO2 (VCO2), consumo de O2 (VO2), equivalentes ventilatórios de O2 (VE/VO2) e de CO2 (VE/VCO2), frações parciais do O2 (PETO2) e do CO2 (PETCO2) no final da expiração, quociente de trocas respiratórias (RER), freqüências respiratória (RR) e cardíaca (FC), além dos valores de potência aplicada e da velocidade de pedalagem no cicloergômetro. Os valores do LAV em exercício foram calculados por quatro diferentes métodos, que usam como critério de medida deste parâmetro, a mudança de inclinação da VCO2, da VE e do PET O2 em relação ao tempo ou da VCO2 em relação ao VO2. Estes métodos foram os seguintes: 1- método Visual VCO2 (M. VISUAL VCO2); 2- método Visual PET O2 (M. VISUAL PET O2); 3- método Automático, usando algoritmo, incorporado ao sistema MedGraphics (M. AUTOMÁTICO); 4- método semi-automático, implementado em nosso Laboratório, baseado no uso de modelos bissegmentados Linear-Linear (M. L-L VCO2) e Linear-Quadrático (M. L-Q VCO2) na condição de resposta da VCO2 em relação ao tempo e em relação ao VO2 (M. L-L VCO2 - VO2 e M. L-Q VCO2 - VO2). Os modelos bissegmentados se basearam na aplicação da soma dos quadrados dos resíduos, quando o conjunto de dados é ajustado pelo método dos mínimos quadrados, para uma reta inicial e final ou uma reta inicial e uma curva quadrática final. Após análise qualitativa e quantitativa apropriada ao conjunto de dados, chegou-se às seguintes conclusões: 1- os valores de LAV calculados pelos métodos visuais VCO2 e PET O2 foram significativamente superiores (p<0,05) aos obtidos pelos métodos Automático e L-L VCO2; 2- o método Visual VCO2 mostrou melhor desempenho do que o método Visual PET O2; 3- os valores do LAV calculados pelos métodos Automático e L-L VCO2 não foram estatisticamente diferentes e ambos subestimaram os valores do LAV, comparativamente aos métodos visuais VCO2 e PET O2 (p<0,05); 4- os métodos baseados em modelos bissegmentados L-L e L-Q mostraram que somente o M. L-L, para o caso da resposta da VCO2 em relação ao tempo, foi útil para medir quantitativamente o LAV; 5- o método semi-automático bissegmentar L-L VCO2 mostrou melhor desempenho do que o método Automático, quando ambos foram comparados qualitativa e quantitativamente (maior porcentagem de casos em que foi possível aplicar o modelo e melhor comportamento dos parâmetros das regressões lineares do LAV, relacionando potência e VO2); 6- o método semi-automático bissegmentar L-L VCO2 se mostrou promissor, no sentido de que possa ser aprimorado e usado, em futuro próximo, como método totalmente automático de determinação do limiar de anaerobiose ventilatório durante o exercício físico dinâmico. / The technological achievements in last decade made possible to use in laboratory facilities digital computerized equipments that allowed the acquisition, storage ande processing of cardiorespiratory variables during exercise on real time basis. Also, as a consequence of these advances, it was possible to apply mathematical models to represent physiological responses under experimental conditions. The present study must be understood in the context above described. It had the the purpose to compare the ventilatory anaerobic threshold (VAT) during dynamic exercise, by four different methods. Two of them are based on visual analyses made on graphic plots of computer monitor, and two others are based on application of mathematical models. Twenty four active and sedentary healthy men were studied in the present project (mean age 33.8 ± 9.2 years). All of them were studied in seated position using an electronic braked cycle ergometer (CORIVAL 400 – Quinton), that allowed the application of ramp powers using a computer software incorporated to the ergoespirometric system (MedGraphics – CPX/D). This system allowed the recording and processing of all cardiorespiratory variables usually needed in exercise physiology, as follow: O2 uptake (VO2), CO2 production (VCO2), minute respiratory ventilation (VE), respiratory equivalent ratio (RER), VE/VO2, VE/VCO2, and end tidal expiratory values of O2 (PET O2) and CO2 (PET CO2), as well as, power and rotation speed cycle ergometer values. The exercise protocol included a four minute period at a minimum power (3 - 4 Watts) followed by a ramp (15 – 35 Watts) adjustable individually on the basis of sex, age and weight of volunteers – the peak power was limited by the occurrence of unpleasant symptons or when the heart rate reached a target age value. The VAT values during exercise were measured by using four different methods: 1- visual loss of linearity related to time (VCO2 VIS. M.); 2- visual response of PET O2 at lowest value before the progressive increase in exercise; 3- automatic detection using MedGraphics algorithm; 4- semiautomatic method using bisegmentar mathematical models (Linear-Linear and Linear-Quadratic) applied to VCO2 and VE in relation to time (VCO2 L-L M.; VCO2 L-Q M.; VE L-L M.; VE L-Q M.) and to VCO2 in relation to VO2 during exercise (VCO2 vs. VO2 L-L M.; VCO2 vs. VO2 L-Q M.). The bisegmentar models were based on the measure of the square sum of residual values related to fitting of two functions, Linear-Linear and Linear-Quadratic, appling the least-square method. After qualitative and quantitative analyses of data, it was possible to reach to the following conclusions: 1- the VAT values measured by VCO2 and PET O2 visual methods were higher (p<0.05) than the ones obtained by Automatic and semi automatic methods; 2- the Visual VCO2 compared to PET O2 method, presented a better performance when VO2 and power values are represented by regression lines; 3- the VAT values obtained by Automatic and semiautomatic methods were not statistically different and have shown lower values when compared to visual methods (VCO2 and PET O2); 4- comparing the performance of the all bisegmentar methods tested, only the VCO2 L-L related to time was useful for measuring the VAT; 5- compared to Automatic method, the VCO2 L-L method could be applied in higher percentage of cases and presented parameters of regression lines (inclination and intercept) closer to visual methods; 6- the semiautomatic method applied to the response VCO2 in relation to time has shown a promising method that if fully automatic may be useful to calculate VAT in men.
23

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.
24

Stratification of perioperative risk in patients undergoing major hepato-pancreatico-biliary surgery using cardiopulmonary exercise testing

Junejo, Muneer January 2013 (has links)
Contemporary hepatobiliary surgery practice must accurately assess operative risk in increasingly elderly populations with greater co-morbidity. Current methods fail to identify patients at high risk of postoperative complications. Cardiopulmonary exercise testing (CPET) derived anaerobic threshold (AT) and ventilatory equivalence of carbon dioxide (VE/VCO2) are validated predictors of postoperative outcome in major intra-abdominal surgery and outperform contemporary tools of risk evaluation. Despite evidence of improved in-hospital postoperative survival in large centres offering complex curative hepatobiliary surgery, morbidity remains high and long-term survival in the high-risk subset remains poor. This thesis investigated the role of validated CPET-derived markers in predicting perioperative outcomes for a high-risk hepatobiliary surgery population. It was also utilised to study the impact of malignant obstructive jaundice on peripheral oxygen extraction. In a prospective cohort of high-risk patients undergoing liver resection, an AT of 9.9 ml O2/kg/min predicted in-hospital mortality and long-term survival. Below this threshold, AT was 100% sensitive and 75.9% specific for in-hospital mortality (PPV 19%, NPV 100%). Long-term survival below the threshold of 9.9 was significantly worse when compared to those above (mortality HR 1.81). The VE/VCO2 was the most significant predictor of postoperative complications and a threshold of 34.5 provided 84% specificity and 47% sensitivity (PPV 76%, NPV 60%). Amongst the high-risk pancreaticoduodenectomy patients, VE/VCO2 was the single most predictive marker of in-hospital postoperative mortality with an AUC of 0.850 (p=0.020); a threshold value 41 was 75% sensitive and 94.6% specific (PPV 50%, NPV 98.1%). The VE/VCO2 41 was also the only predictor of poor long-term survival (HR 1.90). Notably, AT, Revised Cardiac Risk Index and Glasgow Prognostic Score did not predict outcome after pancreaticoduodenectomy. Patients with malignant obstructive jaundice, evaluated for peripheral oxygen extraction using CPET, showed lower mean peak oxygen consumption (peak VO2) at 63±17.4% of the predicted value. This was noted in absence of any significant pre-existing cardiopulmonary disease and normal respiratory reserve. Normal patterns of oxygen extraction were seen at rest, during incremental work rate and peak exercise levels. Levels of oxygen partial pressure and saturation exceeded baseline values after exercise signifying normal microcirculatory responses. Thus, aerobic capacity was limited by dysfunction in delivery (cardiac output) rather than oxygen extraction. CPET provides useful prognostic adjuncts for early and long-term outcomes in the high-risk patients undergoing major hepatobiliary surgery. These findings provide useful tools for perioperative optimisation of the high-risk patient and plan appropriate level of postoperative care to address mortality and morbidity after surgery.
25

Mechanical power output during cycling : the efficacy of mobile power meters for monitoring exercise intensity during cycling

Nimmerichter, Alfred January 2011 (has links)
One of the most meaningful technical innovations in cycling over the past two decades was the development of mobile power meters. With the ability to measure the physical strain under “real world” outdoor conditions, the knowledge of the demand during cycling has improved enormously. Power output has been described as the most direct measure of intensity during cycling and consequently power meters becomes a popular tool to monitor the training and racing of cyclists. However, only limited research data are available on the utilisation of power meters for performance assessment in the field or the analysis of training data. Therefore, the aims of the thesis were to evaluate the ecological validity of a field test, to provide an extensive insight into the longitudinal training strategies of world-class cyclists and to investigate the effects of interval training in the field at difference cadences. The first study aimed to assess the reproducibility of power output during a 4-min (TT4) and a 20-min (TT20) time-trial and the relationship with performance markers obtained during a laboratory graded exercise test (GXT). Ventilatory and lactate thresholds during a GXT were measured in competitive male cyclists (n = 15; VO2max 67 ± 5 mL . min−1 . kg−1; Pmax 440 ± 38 W ). Two 4- min and 20-min time-trials were performed on flat roads. Strong intraclass-correlations for TT4 (r = 0.98; 95 % CL: 0.92-0.99) and TT20 (r = 0.98; 95 % CL: 0.95-0.99) were observed. TT4 showed a bias ± random error of −0.8 ± 23W or −0.2 ± 5.5%. During TT20 the bias ± random error was −1.8 ± 14 W or 0.6 ± 4.4 %. Both time-trials were strongly correlated with performance measures from the GXT (p < 0.001). Significant differences were observed between power output during TT4 and GXT measures (p < 0.001). No significant differences were found between TT20 and power output at the second lactate-turn-point (LTP 2) (p = 0.98) and respiratory compensation point (RCP) (p = 0.97). In conclusion, TT4 and TT20 mean power outputs are reliable predictors of endurance performance. TT20 was in agreement with power output at RCP and LTP 2. Study two aimed to quantify power output (PO) and heart rate (HR) distributions across a whole season in elite cyclists. Power output and heart rate were monitored for 11 months in ten male (age: 29.1 ± 6.7 y; VO2max: 66.5 ± 7.1 mL . min−1 . kg−1) and one female (age: 23.1y; VO2max: 71.5 mL . min−1 . kg−1) cyclist. In total, 1802 data sets were sampled and divided into workout categories according to training goals. The PO at the RCP was used to determine seven intensity zones (Z1-Z7). PO and HR distributions into Z1-Z7 were calculated for all data and workout categories. The ratio of mean PO to RCP (intensity factor, IF) was assessed for each training session and for each interval during the training sessions (IFINT). Variability of PO was calculated as coefficient of variation (CV ). There was no significant difference in the distribution of PO and HR for the total season (p = 0.15), although significant differences between workout categories were observed (p < 0.001). Compared with PO, HR distributions showed a shift from low to high intensities. IF was significantly different between categories (p < 0.001). The IFINT was related to performance (p < 0.01), although the overall IF for the session was not. Also, total training time was related to performance (p < 0.05). The variability in PO was inversely associated with performance (p < 0.01). In conclusion, HR accurately reflects exercise intensity over a total season or low intensity workouts but is limited when applied to high intensity workouts. Better performance by cyclists was characterised by lower variability in PO, greater training volume and the production of higher exercise intensities during intervals. The third study tested the effects of low-cadence (60 rev . min−1) uphill (Int60) or high-cadence (100 rev . min−1) flat (Int100) interval training on PO during 20 min uphill (TTup) and flat (TTflat) time-trials. Eighteen male cyclists (VO2max: 58.6 ± 5.4 mL . min−1 . kg−1) were randomly assigned to Int60, Int100 or a control group (Con). The interval training comprised of two training sessions per week over four weeks, which consisted of 6 bouts of 5 min at the PO at RCP. For the control group, no interval training was conducted. A two-factor ANOVA revealed significant increases on performance measures obtained from GXT (Pmax: 2.8 ± 3.0 %; p < 0.01; PO and VO2 at RCP: 3.6 ± 6.3 % and 4.7 ± 8.2 %, respectively; p < 0.05; and VO2 at ventilatory threshold: 4.9 ± 5.6 %; p < 0.01), with no significant group effects. Significant interactions between group and the uphill and flat time-trials, pre vs. post-training on time-trial PO were observed (p < 0.05). Int60 increased PO during both, TTup (4.4 ± 5.3 %) and TTflat (1.5 ± 4.5 %), whereas the changes were − 1.3 ± 3.6 %; 2.6 ± 6.0 % for Int100 and 4.0 ± 4.6 %; − 3.5 ± 5.4 % for Con, during TTup and TTflat, respectively. PO was significantly higher during TTup than TTflat (4.4 ± 6.0 %; 6.3 ± 5.6 %; pre and post-training, respectively; p < 0.001). These findings suggest that higher forces during the low-cadence intervals are potentially beneficial to improve performance. In contrast to the GXT, the time-trials are ecologically valid to detect specific performance adaptations.
26

Porovnání metodik identifikace anaerobního prahu v cyklistické části triatlonu / Comparison of methods of identification of anaerobic threshold in the cycling part of triathlon

Berka, Martin January 2014 (has links)
Tittle: Comparison of methodologies for the identification of anaerobic threshold in cycling part of the triatlon Triathlon is an endurance sport combining in a complex of three different sports - swimming, cycling and running. It is a time-consuming sport, where the effectiveness of the training must be at a high level. From the structure of performance in triathlon and the related management training results as the most important prerequisite of effective training to know the individual tracks heart rate and achieved watt performance on the level of the individual anaerobic threshold. To identify and track these values using are used continuous measurements and verifications. One of the most commonly used methods is load diagnostics. Objective: The aim of the thesis is to research literature on load diagnostics. Based on the findings obtained to choose the most frequently used diagnostic test load, which is than applied to the experimental group and the results are statistically compared showing whether there are signifiant differences in the results obtained from the use of different tests. Furthermore, to continue to determine which tests are the most appropriate for evaluation of fitness triathlon in the cycling part of the triathlon. Methodology: The selection and use of selected tests:...
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Análise de existência de máxima fase estável de lactato em exercício resistido em população jovem e idosa / Maximal lactate steady analysis in resistance exercise in young and older groups

Sousa, Nuno Manuel Frade de 27 October 2010 (has links)
A máxima fase estável do lactato (MFEL) é considerada uma intensidade critica em exercício dinâmico e sua intensidade é específica do grupo etário. No entanto, apesar da relação existente entre a intensidade de esforço e os ajustes cardiovasculares, metabólicos e ventilatórios durante o exercício resistido, a MFEL foi muito pouco estudada neste tipo de exercício. O objetivo do estudo foi verificar e comparar a existência de MFEL nos exercícios leg press (LP) e supino reto (SR) em dois grupos: jovens e idosos. Além disso, analisar o comportamento das variáveis ergoespirométricas (VE, VO2 e VCO2), lactacidemia, freqüência cardíaca (FC), pressão arterial (PA) e percepção subjetiva de esforço (PSE) na intensidade da MFEL. Foram avaliados 13 homens jovens (26,1 +/- 2,9 anos) e 11 idosos (68,9 +/- 4,0 anos) saudáveis e com experiência mínima de 6 meses em treinamento resistido, que passaram por teste de 1 repetição máxima (1RM), teste crescente para determinação do limiar anaeróbio (LAn) e mais três sessões para a determinação da MFEL. Todas as sessões foram realizadas no mesmo horário do dia, separadas por 48 a 72 horas de intervalo. O LAn, expresso em %1RM, foi significativamente superior no LP em relação ao SR para os dois grupos estudados (LP: 27,8 +/- 3,6 %1RM nos jovens e 27,9 +/- 5,0% 1RM nos idosos; SR: 24,0 +/- 3,0% 1RM nos jovens e 21,5 +/- 3,1% 1RM nos idosos). Não foram observadas diferenças estatisticamente significativas na intensidade do LAn entre os grupos em cada aparelho. A lactacidemia na intensidade do LAn foi significativamente inferior no LP (1,86 +/- 0,63 mmol/L nos jovens e 1,23 +/- 0,34 mmol/L nos idosos) em relação ao SR (2,08 +/- 0,41 mmol/L nos jovens e 1,91 +/- 0,40 mmol/L nos idosos). A intensidade da MFEL no grupo de jovens foi 29,2 +/- 6,7% 1RM no LP e 21,7 +/- 4,4% 1RM no SR. No grupo e idosos, a MFEL ocorreu a 30,9 +/- 4,9% 1RM no LP e 23,3 +/- 6,6% 1RM no SR. A MFEL ocorre em intensidade significativamente menor no aparelho SR para os dois grupos (p < ou = 0,05), sem diferenças estatisticamente significativas entre os grupos. Não houve diferença significativa entre as intensidades do LAn e da MFEL para os dois grupos nos dois aparelhos. Durante a realização do exercício na MFEL, ocorreu a estabilização dos parâmetros ergoespirométricos, FC, PA e PSE entre a série 9 e série 15. Estes resultados demonstram que é possível determinar MFEL nos exercícios LP e SR para as duas populações estudadas. A MFEL ocorre em intensidades superiores no exercício LP. A intensidade da MFEL, expressa em percentual de 1RM, é semelhante à intensidade do LAn. / The maximal lactate steady state (MLSS) is considered a critical intensity of dynamic exercise and its intensity is specific to the age group. However, despite the relationship between exercise intensity and cardiovascular, metabolic and ventilatory adjustments during resistance exercise, the MLSS was unknown in this type of exercise. The purpose of the study was to verify and to compare if there is a maximal lactate steady state (MLSS) for leg press (LP) and bench press (BP) exercises in two different groups: young and older people. Furthermore, to evaluate the ventilatory responses (VE, VO2 e VCO2, blood lactate concentration (BLC), heart rate (HR), blood pressure and rate of perceived exertion (RPE) to those exercises performed on MLSS intensity. 13 young men (26,1 +/- 2,9 years) and 11 elderly healthy men (68,9 +/- 4,0 years) with a minimal experience of 6 months of resistance training volunteered for the study. Volunteers underwent a 1 repetition maximum test (1RM), an incremental test to determine anaerobic threshold (AT) and three more sessions to determine MLSS. Session were performed on the same time of day and separated by a 48-72 h interval. AT intensity (%1RM) was significantly higher for LP than BP for the two groups studied (LP: 27,8 +/- 3,6% 1RM for young group and 27,9 +/- 5,0% 1RM for elderly; BP: 24,0 +/- 3,0%1RM for young group and 21,5 +/- 3,1%1RM for elderly). There was no significant difference between groups in the AT intensity. BLC on AT was significantly lower for LP (1,86 +/- 0,63 mmol/L for young group and 1,23 +/- 0,34 mmol/L for elderly) than BP (2,08 +/- 0,41 mmol/L for young and 1,91 +/- 0,40 mmol/L for elderly). MLSS intensity for young group was 29,2 +/- 6,7% 1RM in LP and 21,7 +/- 4,4% 1RM in BP. For elderly, MLSS was 30,9 +/- 4,9% 1RM in LP and 23,3 +/- 6,6% 1RM in BP. MLSS intensity was significantly lower in BP for both groups (p < or = 0,05), with no statistical differences between groups. There was no significant difference between AT and MLSS intensities on both groups. During exercise on MLSS, ventilatory parameters, HR, blood pressure and RPE stabilized between set 9 and set 15. These results show that it is possible to identify MLSS on the LP and BP exercises for both populations. MLSS intensity is higher in LP exercise, when compared to BP. MLSS intensity is similar to the AT intensity.
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Limiar ventilatório dois (LV2) e o consumo máximo de oxigênio (VO2max) como preditores de tolerância ao esforço em jogadores de futebol / Ventilatory threshold two (VT2) and maximal oxygen uptake (VO2max) as predictors of tolerance for effort in male soccer players

Silva, Paulo Roberto dos Santos 02 September 2009 (has links)
O objetivo deste estudo foi verificar a relação entre o limiar ventilatório dois (LV2) e o consumo máximo de oxigênio (VO2max) como preditores de tolerância ao esforço em jogadores de futebol. O LV2 e o VO2max foram medidos a um terço de encerramento da temporada. Uma amostra de sessenta atletas futebolistas do sexo masculino, distribuídos nas seguintes posições: (14 zagueiros [23%], 14 laterais [23%], 19 meio campistas [32%] e 13 atacantes [22%]) menos os goleiros. A média de idade era de 20,8 ± 2,8 anos; massa corpórea de 71,9 ± 7,6 kg e estatura de 178 ± 6,5 cm foram avaliadas num estudo transversal. Todos eram assintomáticos, não fumantes, não faziam uso de qualquer medicamento e eram livres de qualquer tipo de distúrbio neuromuscular, cardiovascular, respiratório e circulatório. A média de treinamento no período competitivo consistiu de 10 horas semanais. Todos os jogadores eram de clubes profissionais da primeira divisão do Estado de São Paulo e estavam registrados na Federação Paulista de Futebol.Todos foram submetidos à avaliação cardiorrespiratória e metabólica, utilizando-se analisador metabólico de gases (CPX/D, MedGraphics, EUA) acoplado a eletrocardiógrafo (Max Personal, Marquette, EUA), ambos os sistemas computadorizados. A determinação da capacidade física máxima foi verificada em esteira rolante (Inbramed, ATL10200, BRA) utilizando-se protocolo escalonado contínuo (1 km.h-1 a cada dois minutos) e inclinação fixa de 3%. Os seguintes resultados verificados e os parâmetros utilizados foram: VO2max = 58,8 ± 4,48 mL.kg-1.min-1; VO2LV2 = 49,6 ± 4,96 mL.kg-1.min-1; TTMAX = 1073 ± 124,5s; TTLV2 = 713 ± 106,0s. Análise de regressão linear demonstrou correlação positiva entre o TTMAX vs. VO2max (r = 0,473;p<0,001); VO2LV2 vs. VO2max (r = 0,691; p<0,001); TTLV2 vs. VO2max (r = 0,545; p <0,001); TTMAX vs. TTLV2 (r = 0,560; p < 0,001) e entre TTLV2 vs. VO2LV2 (r = 0,610; p< 0,001). Concluindo, a potência aeróbia máxima associada ao aumento do consumo de oxigênio no LV2, são preditores de uma maior capacitação aeróbia em jogadores de futebol. O melhor parâmetro preditor de tolerância ao exercício em todas as posições foi à relação VO2LV2 vs. VO2max. / The aim of this study was to investigate the relationship between the ventilatory threshold two (VT2) and maximum oxygen consumption (VO2max) as predictors of exercise tolerance in soccer players. VT2 and VO2max were measured when one-third of the soccer season still remained. A sample of sixty male soccer players, distributed in the following position: (14 central-defenders [23%], 14 fullbacks [23%], 19 midfielders [32%] and 13 forwards [22%]) less the goalkeepers, were evaluated a cross-sectional study. The mean age was 20.8 ± 2.7 years, body mass: 71.9 ± 7.62 kg and height: 178.1 ± 6.5 cm. All were asymptomatic, non-smokers, they did not use any medication and were free from any kind of neuromuscular disorder, cardiovascular, respiratory and circulatory. In the competitive season, the average training week consisted of 10 hours practice and games. All the players were professional clubs of the first division of the State of Sao Paulo and were registered in the Paulista Football Federation. All of them underwent a cardiopulmonary and metabolic exercise test evaluation. To this end we used a gas explorer (CPX/D, breathbybreath Medgraphics, Saint Paul, MN, USA) coupled to an electrocardiograph (Max Personal, Exercise Testing System, Marquette, USA). Both systems were computerized. The maximum exercise test was performed on a motor-driven treadmill (Inbramed, ATL-10200, Porto Alegre, BRA), using the incremental continuous exercise protocol. The athletes started the race with 8 km.h-1 and increased speed of 1 km.h-1 every two minutes with fixed slope at 3%. In all tests there was verbal encouragement. The results verified and the parameters used were: VO2max = 58.8 ± 4.48 mL.kg-1.min-1; VO2VT2 = 49.6 ± 4.96 mL.kg-1.min-1; MAXTT = 1073 ± 124.5s; TTVT2 = 713 ± 106s. Linear regression analysis in male soccer players showed positive correlation between the VO2max vs. MAXTT to exercise (R = 0.473; p < 0.001); VO2VT2 vs. VO2max (R = 0.691; p < 0.001); TTVT2 vs. VO2max (R = 0.545; p < 0.001); MAXTT vs. TTVT2 (R=0.560; p < 0.01) and between TTVT2 vs. VO2VT2 (R=0.610; p < 0.001). The results allowed us to infer that the attainment of maximum aerobic power together with increased of VO2VT2 are predictors of a higher aerobic capacity in soccer players. The best predictive parameter of exercise tolerance in all positions was the relationship VO2VT2 vs. VO2max.
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Cinética da glicemia e lactatemia em diabéticos tipo 2 durante e após exercício aeróbio realizado em diferentes intensidades

Carvalho, Wolysson Hiyane de 12 December 2006 (has links)
Made available in DSpace on 2016-06-24T04:15:34Z (GMT). No. of bitstreams: 1 Texto Completo.pdf: 617036 bytes, checksum: ac8c33b1b5f5f9f68bc50c8d536970e6 (MD5) Previous issue date: 2006-12-12 / With the purpose of analyzing the blood glucose responses during and after exercise performed at 90 and 110% of anaerobic threshold (AT) and compare the intensity of lactate threshold (LT) with the intensity of delta lactate (DL), 14 type-2 diabetic patients (DM2) (60±11 years; 79±15 Kg; 162±6.5 cm) performed an incremental test (IT) on cycle ergometer. After the IT for AT identification, participants to three experimental sessions on different days: a 20 min of cycling either at 90 or 110% of AT (with the identification of DL) and a control session (CON). Blood glucose was measured at rest, 10 and 20th min of exercise or control condition, as well as at each 15 min during a 2 hour post-exercise recovery period (Rec). Test t-student no identified differences significant between LT and DL of variation 0. The One Way ANOVA did not identify significant differences in blood glucose between the 90 and 110% AT session. Both exercise intensities induced a significant decrease in blood glucose compared to CON, a significant decrease was observed at the 20th min of exercise (-41 + 15 mg.dl-1), and at the 15th min (-48 + 21 mg.dl-1) and 60th min of Rec from the 90% of AT session. It was also observed a significant decrease at 10 and 20 min of exercise and at 15th, 30th, 45th, 60th and 90th min of Rec from the session at 110% of AT. The exercise performed at a higher intensity (110% AT) resulted in a higher hypoglicemiant effect and may be an alternative of exercise intensity to better control the blood glucose for type 2 diabetics well no have cardiovascular complications or other restrictions to exercise performed above the AT. The DL of variation 0 can be used as a submaximum method to identify of the LT. / Com o propósito de analisar a resposta da glicose sanguínea durante e após exercício a 90 e 110% do limiar anaeróbio (LA) e comparar a intensidade do limiar de lactato (LL) com a intensidade do delta de lactato (DL), 14 voluntários diabéticos tipo 2 (DM2) (60 ± 11 anos; 79 ± 15 Kg; 162 ± 6,5 cm), realizaram um teste incremental (TI) em cicloergômetro. Após realização do teste incremental para identificação do LA, os voluntários realizaram 3 sessões experimentais em dias distintos: 20 minutos em bicicleta ergométrica a 90 e 110% LA (com a identificação do DL) e uma sessão controle (CON). Glicose sanguínea foi mensurada no repouso, aos 10 e 20 min do exercício ou na situação controle, bem como a cada 15 minutos durante 2 horas do período de recuperação pós-exercício (Rec). Teste t-student não identificou diferenças significantes entre LL e DL de variação 0 .ANOVA não identificou diferenças significantes nas concentrações de glicose sanguínea durante e após as sessões de 90 e 110% do LA. Ambas intensidades de exercício promoveram uma diminuição significativa nas concentrações de glicose comparadas ao CON. Redução significativa da glicemia foi observada aos 20 min de exercício (-41 + 15 mg.dl- 1), aos 15 min (-48 + 21 mg.dl-1) e 60 min da Rec pós sessão a 90% do LA enquanto que foi observada uma queda significativa da glicemia aos 10 e 20 min do exercício e aos 15, 30, 45, 60 e 90 min da Rec após sessão de 110% LA ambas em relação ao controle. O exercício de maior intensidade (110% LA) resultou em maior efeito hipoglicemiante e pode ser uma alternativa para um melhor controle da glicose sanguínea em diabéticos tipo 2 que não possuam problemas cardiovasculares ou outras complicações e restrições ao exercício realizado acima do LA. O DL de variação 0 poderia ser utilizado como um método submáximo para identificar o LL.
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Confiabilidade de um circuito multimodal incremental na determinação do limiar anaeróbio de idosos por meio da dosagem do lactato sanguíneo / Reliability of an incremental multi-modal circuit in the determination of the anaerobic threshold of elderly people through the dosage of the blood lactate

Lana, Daniel Martinez 21 August 2018 (has links)
A prática regular de exercício físico traz inúmeros benefícios para os idosos, mas é necessário identificar uma prescrição de treinamento que possa ser realizada de maneira segura e eficaz por esta população. O Treinamento Multimodal é uma alternativa para estimular as capacidades e habilidades físicas importantes para a manutenção da saúde e autonomia no envelhecimento. O objetivo deste estudo, de abordagem quantitativa e delineamento quase-experimental, foi medir a confiabilidade de um circuito multimodal incremental na determinação do limiar anaeróbio (LAN) de idosos por meio da dosagem do lactato sanguíneo. O estudo foi aprovado por Comitê de Ética em Pesquisa. Foram identificadas variáveis sociodemográficas e clínicas. As variáveis clínicas foram medidas antes, durante e após sessões de treinamento em um circuito multimodal. Para as análises descritivas, foram calculadas as frequências absolutas, porcentagens, medianas, médias e desvio padrão. Para a análise de confiabilidade intraobservador e de concordância, foram utilizados o Coeficiente de Correlação Intraclasse (CCI) e o teste de concordância Bland-Altman, usando o pacote estatístico SPSS® V24. Para a identificação da igualdade de médias no teste e no reteste foram utilizados os testes paramétricos t-pareado e One-way ANOVA medidas repetidas, para variáveis contínuas e com distribuição normal, tomadas nos momentos antes e depois. Para os casos onde as suposições de normalidade e/ou esfericidade não foram atendidas, foram utilizados os testes não paramétricos de Wilcoxon ou Friedman. A intensidade do limiar anaeróbio (ILAN) e a Frequência Cardíaca na Intensidade do Limiar Anaeróbio (FCILAN) foram identificadas a partir de três critérios. Participaram do estudo 20 idosos, na maioria mulheres, com idade entre 60 e 65 anos, de cor branca, convivendo com companheiro, com mais de 12 anos de escolaridade, aposentados. Ao testar a reprodutibilidade da ILAN em dois momentos distintos com o mesmo avaliador, observamos que a média dos escores obtidos no teste e reteste foi semelhante (>,05) indicando boa correlação entre os pares analisados (r = ,77 a ,91). Nossos resultados também mostraram alta confiabilidade em todos os critérios adotados para determinação do LAN (CCI=,86 a ,95), além de boa concordância das medidas teste e reteste para o LAN2 do 1° e 3° critérios por meio do método de análise Bland-Altman. Identificamos redução da pressão arterial na primeira hora após o treinamento em circuito, em comparação com os valores pré-intervenção, nos momentos teste e reteste. O principal achado de nosso estudo se deu pela confiabilidade e concordância entre as medidas teste-reteste para as variáveis estudadas, sugerindo adequação do circuito multimodal incremental na determinação do LA de idosos por meio da dosagem do Lactato Sanguíneo / Regular physical activity brings several benefits to elderly people, but it\'s necessary to identify a training prescription that can be performed in a safe and effective manner for this population. The Multimodal Training is an alternative to stimulate physical skills and abilities important to maintaining health and autonomy in aging. The purpose of this study, with quantitative approach and quasi-experimental delineation, was to measure the reliability of an incremental multimodal circuit in the determination of the anaerobic threshold (ANT) of elderly people through blood lactate dosage. The study was approved by the Ethics in Research Committee. Social demographic clinical variables were found. Clinical variables were measured before, during and after the training sessions in a multi-modal circuit. For descriptive analysis, absolute frequencies, percentages, medians, averages and standard deviation were calculated. For intra-observer reliability and agreement analysis, we used the Interclass Correlation Coefficient (ICC) and Bland-Altman agreement test, using statistical package, SPSS® V24. To the measures equality identification in the test and retest were used the t-paired parametrics and One-way ANOVA repeated measures, to continuous variables and with normal distribution, taken moments before and after. To the cases where normality and/or spherecity were not satisfied, we used Wilcoxon or Friedman non-parametric tests. The anaerobic threshold intensity (ATI) and the heart rate in the anaerobic threshold intensity (HRATI) were identified according to three criteria. Participated in the study 20 elderly people, mostly women, between the ages of 60 and 65 years old, white colored, living with a partner, with more than 12 years of schooling, retired. When testing the reproducibility of ATI in two different times with the same evaluator, we observed the measure of the obtained scores in the test and retest was similar to (>,05), indicating a good correlation between the analyzed pairs (r = ,77 a ,91). Our results also showed high reliability in all adopted criteria to determine ATI (CCI=,86 a ,95), in addition to the good agreement of the test and retest measures to the ATI2 of the first and third criteria through Bland-Altman analysis method. Was identified arterial pressure reduction in the first hour after the circuit training, compared with preintervention values, in the test and retest moments. The main discovery was given through reliability and agreement between measures test-retest to the studied variables, suggesting adjustment of the incremental multimodal circuit in the determination of the elderly people ATI through blood lactate dosage

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