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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.
41

The determinants of running performance in middle distance female athletes

Mpholwane, Matome Lieghtone 19 August 2008 (has links)
ABSTRACT Male subjects are invariably used to study the physiological determinants of middle distance running performance. Studies that do include females have examined only the aerobic contribution to middle distance running performance. The aim of the present study was to investigate aerobic, anaerobic and muscle function factors that could be used to predict middle distance running performance in female runners. This study was performed at an altitude of 1800m. Eleven middle distance female runners aged 18-20 were selected for the study. Aerobic capacity was assessed by measuring the maximal oxygen consumption (VO2max), running velocity at maximal oxygen consumption (vVO2max), running economy (RE) and onset of blood lactate accumulation (OBLA). The blood lactate curve of each subject was constructed by relating the oxygen consumption, to the plasma lactate concentrations. Anaerobic capacity was determined by measuring the maximum accumulated oxygen deficit (MAOD) on a treadmill. Muscle function was assessed by having the subjects cycle as fast as possible against changing brake weights ranging from heavy to light using a Monark cycle ergometer. The brake force (kg) was related to velocity (rpm).
42

Estudo da segurança e eficácia do exercício aeróbico em pacientes com esclerose sistêmica / Study of safety and efficacy of aerobic exercise in systemic sclerosis patients

Silva, Natália Cristina de Oliveira Vargas e 02 June 2009 (has links)
OBJETIVO: Diversos estudos demonstraram que pacientes com Esclerose Sistêmica possuem capacidade aeróbia reduzida. É relevante avaliar se o exercício aeróbio é seguro e eficaz para estes pacientes. MÉTODO: Sete pacientes com Esclerose Sistêmica e sete controles saudáveis participaram de um programa de oito semanas, que consistiu em atividade aeróbia de intensidade moderada duas vezes por semana. RESULTADOS: Pacientes e controles apresentaram aumento significativo no pico de consumo de oxigênio, e foram capazes de executar uma intensidade de exercício significativamente maior em relação ao pré-teste. O grupo Esclerose Sistêmica demonstrou aumento na saturação de oxigênio no pico do exercício. O escore de Rodnan foi similar antes e após a intervenção, e as úlceras digitais e o fenômeno de Raynaud permaneceram estáveis. CONCLUSÃO: O exercício aeróbio foi seguro e eficaz para pacientes com Esclerose Sistêmica, portanto, aumentar a capacidade aeróbia é uma meta possível no tratamento desta doença. / OBJECTIVES: Several studies have established that Systemic Sclerosis patients have a reduced exercise capacity. It is relevant to evaluate whether aerobic exercise consists in a safe and effective intervention for these patients. METHODS: Seven Systemic Sclerosis patients and seven healthy sedentary controls were enrolled in an eight-week program consisting of moderate intensity aerobic exercise twice a week. RESULTS: Systemic Sclerosis patients and controls had a significant improvement in their peak oxygen consumption and were able to perform a significantly higher exercise intensity when compared to baseline. Systemic sclerosis group improved peak exercise oxygen saturation. Rodnan score was similar before and after the intervention. Digital ulcers and Raynauds phenomenon remained stable. CONCLUSIONS: Aerobic exercise was safe and effective in patients with Systemic Sclerosis, therefore increasing aerobic capacity is a feasible goal in the management of this disease.
43

Estudo da segurança e eficácia do exercício aeróbico em pacientes com esclerose sistêmica / Study of safety and efficacy of aerobic exercise in systemic sclerosis patients

Natália Cristina de Oliveira Vargas e Silva 02 June 2009 (has links)
OBJETIVO: Diversos estudos demonstraram que pacientes com Esclerose Sistêmica possuem capacidade aeróbia reduzida. É relevante avaliar se o exercício aeróbio é seguro e eficaz para estes pacientes. MÉTODO: Sete pacientes com Esclerose Sistêmica e sete controles saudáveis participaram de um programa de oito semanas, que consistiu em atividade aeróbia de intensidade moderada duas vezes por semana. RESULTADOS: Pacientes e controles apresentaram aumento significativo no pico de consumo de oxigênio, e foram capazes de executar uma intensidade de exercício significativamente maior em relação ao pré-teste. O grupo Esclerose Sistêmica demonstrou aumento na saturação de oxigênio no pico do exercício. O escore de Rodnan foi similar antes e após a intervenção, e as úlceras digitais e o fenômeno de Raynaud permaneceram estáveis. CONCLUSÃO: O exercício aeróbio foi seguro e eficaz para pacientes com Esclerose Sistêmica, portanto, aumentar a capacidade aeróbia é uma meta possível no tratamento desta doença. / OBJECTIVES: Several studies have established that Systemic Sclerosis patients have a reduced exercise capacity. It is relevant to evaluate whether aerobic exercise consists in a safe and effective intervention for these patients. METHODS: Seven Systemic Sclerosis patients and seven healthy sedentary controls were enrolled in an eight-week program consisting of moderate intensity aerobic exercise twice a week. RESULTS: Systemic Sclerosis patients and controls had a significant improvement in their peak oxygen consumption and were able to perform a significantly higher exercise intensity when compared to baseline. Systemic sclerosis group improved peak exercise oxygen saturation. Rodnan score was similar before and after the intervention. Digital ulcers and Raynauds phenomenon remained stable. CONCLUSIONS: Aerobic exercise was safe and effective in patients with Systemic Sclerosis, therefore increasing aerobic capacity is a feasible goal in the management of this disease.
44

Deguonies suvartojimo atliekant sunkėjantį krūvį pastovios fazės sąsaja su anaerobiniu pajėgumu / Oxygen consumption during increasing load constant phase interface with anaerobic capacity

Pukelevičiūtė, Asta 28 June 2011 (has links)
Pagrindiniai trys faktoriai lemiantys bėgikų ištvermę yra: maksimalus deguonies suvartojimas (MDS), laktato slenkstis (LS), bei bėgimo ekonomiškumas. Geriausi sportininkai turi panašų MDS, LS, bėgimo ekonomiškumą, bet įrodyta, kad raumenų faktoriai gali įtakoti ištvermę labiau, nei MDS. Yra duomenų, kad sportininkų raumenų galingumą įtakoja anaerobiniai adenozintrifosforo rūgšties (ATP) resintezės procesai, kurie gali turėti įtakos ir aerobinės ištvermės sportininkų varžybų rezultatams. Nustatyta, kad nuosekliai sunkėjančio krūvio (NSK) testo pabaigoje yra didesnis anaerobinis ATP resintezės indėlis. Vadinasi, didesnė raumenų masė ir jėga gali padėti toleruoti vis didėjantį ATP pareikalavimą ir parodyti didesnį deguonies suvartojimo pastovios fazės pasireiškimą. Labai įdomu būtų sužinoti, kaip anaerobinis pajėgumas gali įtakoti ilgų nuotolių bėgikų deguonies suvartojimo pastovios fazės trukmę. Mes manome, kad mūsų gauti tyrimo duomenys, leis geriau suprasti, kokį indėlį anaerobinis pajėgumas vaidina skirtingos deguonies suvartojimo pastovios fazės trukmės pasireiškime. Tyrimo tikslas – Nustatyti deguonies suvartojimą atliekant sunkėjantį krūvį ir pastovios fazės sąsaja su anaerobiniu pajėgumu. Tyrimo objektas: anaerobinio pajėgumo poveikis deguonies suvartojimo kaitai sunkėjančio krūvio metu. Tyrimo uždaviniai: 1. Palyginti aerobinio ir anaerobinio pajėgumo rodiklius tarp bėgikų pasiekiančių ilgesnę ir trumpesnę pastovią fazę. 2. Nustatyti koreliacinį ryšį tarp aerobinių ir... [toliau žr. visą tekstą] / Key words: aerobic capacity, anaerobic test, blood lactate concentration, long – distance runners. The three main factors determining runners endurance are: maximum oxygen consumption, lactate threshold and running economy. However, among the best sportsmen of similar maximum oxygen uptake, lactate threshold and running economy has been shown that muscular factors may influence the endurance more than the maximum oxygen consumption. There is evidence that the athletes' muscle power affects the ATP resynthesis anaerobic processes that may affect the aerobic and endurance sports events. showed that a consistent worsening at the end of the test is more anaerobic ATP contribution resynthesis, thus more muscle mass and strength can help to tolerate the increasing demand of ATP longer a burden, and to show increased oxygen consumption in stable phase of occurrence. It is interesting to learn how to influence the anaerobic capacity for long-distance runners' oxygen consumption in stable phase duaration. Therefore, our survey data to obtain a better understanding of the contribution of anaerobic capacity plays a different oxygen consumption constant phase term occurs. The study objective – identify the oxygen uptake during increasing workload constant phase interface with the anaerobic capacity. The object of the study – anaerobic capacity effects on the oxygen consumption change during increasing exercise load. Study tasks: 1. To compare the aerobicand anaerobic capacity in... [to full text]
45

Efeito do nível do treinamento aeróbio na determinação do limite superior do domínio pesado no ciclismo /

Caritá, Renato Aparecido Corrêa. January 2011 (has links)
Orientador: Camila Coelho Greco / Banca: Fabrizio Caputo / Banca: Dalton Muller Pessoa Filho / Resumo: O principal objetivo deste estudo foi analisar e comparar as respostas metabólicas e cardiorrespiratórias durante o exercício realizado na MLSS e PC em indivíduos com diferentes níveis de treinamento aeróbio no ciclismo. Participaram do estudo 7 ciclistas (C) bem treinados, especializados em provas de estrada e 9 sujeitos não treinados (NT), sem experiência prévia de treinamento no ciclismo. Os voluntários realizaram em dias diferentes os seguintes testes, em um cicloergômetro: 1) teste incremental até a exaustão para a determinação do limiar anaeróbio (Lan), consumo máximo de oxigênio ( O2max) e da intensidade correspondente ao O2max (I O2max); 2) 2 a 4 testes de carga constante de 30 minutos em diferentes intensidades para a determinação da máxima fase estável de lactato sanguíneo (MLSS); 3) 3 testes de carga constante a 95, 100 e 110% I O2max até a exaustão voluntária para a determinação da potência crítica (PC), e; 4) um teste de carga constante até a exaustão na PC. A MLSS foi considerada como a maior intensidade de exercício onde a concentração de lactato não aumentou mais do que 1 mM entre o 10o e o 30o minuto de exercício. Os valores individuais de potência (95, 100 e 110% I O2max) e seu respectivo tempo máximo de exercício (tlim) foram ajustados a partir do modelo hiperbólico de 2 parâmetros para determinação da PC. A PC para ambos os grupos C (318 ± 29W) e NT (200 ± 33W) foi maior significantemente do que a MLSS para os C (288 ± 35W) e NT (169 ± 34W). A MLSS e a PC foram significantemente maiores no grupo C. Em valores relativos ao O2max a MLSS foi maior no grupo C (83 ± 7%) do que no grupo NT (79 ± 6), porém a PC foi similar entre os grupos (91 ± 5% e 90 ± 5%, respectivamente). Da mesma forma, o consumo de oxigênio na PC ( O2PC) foi significantemente maior do que na MLSS ( O2MLSS) nos grupos NT... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The objective of this study was to analyze and to compare metabolic and cardiorrespiratory responses durin the exercise performed at MLSS and CP in subjects with different aerobic trainning levels in cycling. Participated of this study, 7 well trained cyclists (C), specialized in road events and 9 non-trained subjects (NT), without previous training experience in cycling. Ths subjects performed the following protocols in different days in cyclergometer: 1) incremental test until exhaustion to determine anaerobic threshold (AT), maximal oxygen uptake ( O2max) and the intensity at O2max (I O2max); 2) 2 to 4 constant workload tests in different intensities to determine maximal lactate steadystate (MLSS); 3) 3 constant workload tests at 95, 100 e 110% I O2max until exhaustion to determine critical power (CP), and; 4) constant workload test until exhaustion at CP. MLSS was considered the highest exercise intensity at which the blood lactate concentration did not increase for more than 1 mM between 10th and 30th minute of the exercise. The individual values of power (95, 100 e 110% I O2max) and the respective times (tlim) were adjusted using the hyperbolic model with parameteres to determine CP. CP for C (318 ± 29W) and NT (200 ± 33W) was significantly higher than MLSS in C (288 ± 35W) and NT (169 ± 34W). MLSS and PC were significantly higher in C group. In values relative to O2max, the MLSS was significantly higher in C (83 ± 7%) than NT (79 ± 6), however CP was similar between groups (91 ± 5% and 90 ± 5%, respectively). In the same way, the oxygen uptake at CP ( O2PC) was significantly higher than at MLSS ( O2MLSS) for NT (2627 + 519 e 2323 ± 460 mL.min-1, 11%) e C (3607 ± 505 e 3953 ± 466 mL.min-1, 8%). The slow component at CP in C (375 ± 164 ml.min-1) was similar to NT (412 ± 175 ml.min-1). At this condition, the O2max was not attained (C - 93 ± 5%; NT - 96 ± 7%)... (Complete abstract click electronic access below) / Doutor
46

Determinação da contribuição anaeróbia durante o desempenho do nado crawl em distâncias curtas e médias-curtas, entre homens e mulheres / Determination of the anaerobic contribution in short and medium-short front crawl swimming performance between men and women

Bravo, Valter Akira [UNESP] 27 July 2018 (has links)
Submitted by VALTER AKIRA BRAVO (valterovarb@hotmail.com) on 2018-08-10T21:38:41Z No. of bitstreams: 1 dissertação final - valter com ficha catalográfica e aprovação.pdf: 2060934 bytes, checksum: afdb81670103de47e094031d7f61ba46 (MD5) / Approved for entry into archive by Ana Paula Santulo Custódio de Medeiros null (asantulo@rc.unesp.br) on 2018-08-13T11:39:36Z (GMT) No. of bitstreams: 1 bravo_va_me_rcla.pdf: 1991723 bytes, checksum: 1af34f48af2fad362dcac01855af8018 (MD5) / Made available in DSpace on 2018-08-13T11:39:37Z (GMT). No. of bitstreams: 1 bravo_va_me_rcla.pdf: 1991723 bytes, checksum: 1af34f48af2fad362dcac01855af8018 (MD5) Previous issue date: 2018-07-27 / Está bem estabelecido que a contribuição glicolítica anaeróbia é predominante nos eventos próximos a 50 e 100 metros, e que a contribuição aláctica alcança sua maior capacidade de contribuição próximos aos 50 metros. Todavia, pode-se questionar se a taxa de ajuste do metabolismo anaeróbio não seria mais apropriada para analisar os desempenhos de curta duração (50 e 100 metros), ao invés da demanda total. Bem como, pouco se sabe se AOD e as demandas de cada metabolismo (láctico vs. aláctico vs aeróbio) tendem a apresentar respostas diferentes entre sexos. Assim, o objetivo do presente estudo foi analisar o déficit acumulado de oxigênio (AOD) nos desempenhos do crawl em distâncias de 50, 100 e 200 metros, comparando-o pelo método da variação da resposta lactacidêmica e perfil aláctico da curva de débito oxigênio. Participaram deste estudo 12 (doze) nadadores homens (16,8 ± 2,2 anos, 179,3 ± 7,0 cm e 69,4 ± 7,8 kg) e 10 (dez) nadadoras (15,5 ± 3 anos, 161,8 ± 6,2 cm e 55,5 ± 6,8 kg). Todos realizaram o desempenho máximo para as distâncias de 50, 100 e 200 metros para a determinação do O2 acumulado. Após 24 horas, os nadadores desempenharam um teste incremental escalonado máximo e descontínuo (TIE: 6x250m e 1x200m, 50 a 100% da v200m) para a avaliação do V̇O2max e obtenção da relação V̇O2 vs. velocidade de nado em intensidades submáximas. A partir desta relação, projetou-se a demanda de O2 nas velocidades correspondentes ao 50, 100 e 200m foi estimada. Em seguida, a permuta gasosa pulmonar também foi analisada durante os desempenhos de 50, 100 e 200m para se obter a oferta de O2 durante e após cada distância. A estimativa de AOD foi realizada pela comparação entre demanda e oferta de O2. A fase rápida de decaimento exponencial da curva de recuperação do O2, após cada distância de nado, estimou a contribuição aláctica. Enquanto que o equivalente de O2 para a variação da resposta do lactato sanguíneo foi utilizada para reconstruir a demanda anaeróbia láctica. Em todos os testes, o V̇O2 foi obtido respiração-a-respiração por uma unidade metabólica automatizada e portátil (CPET K4b2), que esteve acoplada a um snorkel específico e validado na natação (new-AquaTrainer®). O teste ANOVA (uma entrada, com Sidak como post-hoc) comparou as médias do perfil metabólico entre homens e mulheres para cada distância de desempenho (50, 100 e 200 metros). O nível de significância foi estabelecido em ρ≤0,05. Os resultados preliminares indicam que o V̇O2max correspondeu à 4012,3 ± 453,3 ml×min-1 entre homens e à 3043 ± 335,6 ml×min-1 entre as mulheres. a demanda anaeróbia (AOD) é maior entre as mulheres (50m: 26,2  5,6 mlO2×kg-1; 100m: 43,3  10,2 mlO2×kg-1; 200m: 62,8  15,4 mlO2×kg-1) quando comparadas aos homens (50m: 19,7  3,9 mlO2×kg-1; 100m: 33,6  10,6 mlO2×kg-1; 200m: 48,3  15,7 mlO2×kg-1). Todavia, essas diferenças, quando analisada pela relação percentual entre Déficit/Demanda Acumulada de O2, mostram-se significativas em 50m (P=0,05), mas não em 100m (P=0,32) e 200m ( P=0,47). Ao ponderar pela distância de nado, o AOD (em mlO2×kg-1×m-1) evidenciou tendência decrescente entre as distâncias de nado (significativa apenas ao comparar 50m e 100m vs. 200m, P<0,01 e P<0,05, respectivamente), bem como as diferenças entre sexos não foram significativas ao compará-los em 50m (H: 0,39 e M: 0,52 mlO2×kg-1×m-1, P=0,122), em 100m (H: 0,33 e M: 0,43 mlO2×kg-1×m-1, P=0,741) e em 200m (H: 0,24 e M: 0,31 mlO2×kg-1×m-1, P=0,948). Durante o desempenho nas distâncias de 50, 100 e 200 metros, os perfis de ativação e parcela de contribuição de cada metabolismo energético apresenta a taxa absoluta (mlO2×kg-1) aláctica mais elevada em homens, quando comparada à ativação em mulheres, que demonstram desempenho com predomínio láctico nas distâncias. As diferenças na produção energética entre os sexos mostram valores distintos apenas para a produção aláctica em 50m (P=0,039). Assim, mulheres não apresentam restrições para o suprimento energético anaeróbio, em velocidades supra-máximas de nado, quando essa demanda é estimada pelo método AOD tradicional. Porém, os valores relativos de contribuição dos metabolismos tendem a não serem similares entre homens e mulheres na construção da demanda anaeróbia total (29,2% (50 metros), 15,8% (100 metros) e 29,3% (em 200 metros) superior em homens), causada pela maior ativação do metabolismo aláctico (64,7%, 47,4% e 60,9%) em cada uma destas distâncias. Essa maior contribuição anaeróbia aláctica em homens pode ser um efeito produzido pelas diferenças de massa muscular, sugerindo o desenvolvimento da massa magra para melhorar o desempenho em tarefas com demanda anaeróbia elevada. / It is well established that the anaerobic glycolytic contribution is predominant in events close to 50 and 100 meters, and that the alactic contribution reaches its greatest capacity of contribution close to 50 meters. However, one question that needs to be asked is whether a rate of anaerobic metabolism adjustment is no longer useful for analyzing short-term performance (50 and 100 meters), as opposed to total demand. As well as, little is known if AOD and the demands of each metabolism (lactic vs. alactic vs aerobic) tend to present different responses between genders. Thus, the objective of the present study was to analyze the accumulated oxygen deficit (AOD) in crawl performance at distances of 50, 100 and 200 meters, comparing it by the lactacidemic response and alactic profile of the recovery curve Twelve (12) male swimmers (16.8 ± 2.2 years, 179.3 ± 7.0 cm and 69.4 ± 7.8 kg) and 10 (ten) female swimmers (15.5 ± 3 years old, 161.8 ± 6.2 cm and 55.5 ± 6.8 kg)) participated in this study. All participants were performed a maximal effort at 3 distances (50, 100 and 200 meters) for the determination of accumulated O2 After 24 hours, swimmers performed a maximum and discontinuous step incremental test (TIE: 6x250m and 1x200m, 50 to 100% of v200m) for an evaluation of V̇O2max and obtaining the VO2 vs. swimming speed relationship. From this relation, the demand for O2 at the velocities corresponding to 50, 100 and 200m was estimated. Then, gas exchange was also analyzed during the exercises of 50, 100 and 200m for an O2 supply during and after each distance. The AOD estimate was made by comparing demand and supply of O2. The energy produced from anaerobic alactic metabolism was estimated from the fast component of the post V̇O2. The net energy produced from anaerobic lactic acid metabolism was determined from [La-]net. In all tests, VO2 was obtained breath-by-breath by an automated and portable metabolic unit (CPET K4b2), which was coupled to a specific and validated swimming snorkel (new-AquaTrainer®). The ANOVA test (an entry, with Sidak as a post-hoc) compared the medias of the metabolic profile between men and women for each distance of performance (50, 100 and 200 m). The level of significance was set at ρ≤0.05. Preliminary results indicate that VO2max corresponded to 4012.3 ± 453.3 ml×min-1 for men and 3043 ± 335.6 ml×min-1 for women. Anaerobic demand (AOD) is higher among women (50m: 26,2  5,6 mlO2×kg-1; 100m: 43,3  10,2 mlO2×kg-1; 200m: 62,8  15,4 mlO2×kg-1) than in men (50m: 19,7  3,9 mlO2×kg-1; 100m: 33,6  10,6 mlO2×kg-1; 200m: 48,3  15,7 mlO2×kg-1). However, these differences, when analyzed by the percentage ratio between O2 Accumulated Deficit / Demand, are significant in 50m (P=0,05, but not in 100m (P = 0.32) and 200m (P = 0.47). When considering swimming distance, the AOD (in mlO2×kg-1×m-1) showed a decreasing trend between swimming distances (significant only when comparing 50m and 100m vs. 200m, P <0.01 and P <0.05, respectively), as well as the differences between sexes were not significant when comparing them in 50m (H: 0,39 e M: 0,52 mlO2×kg-1×m-1, P=0,122), in 100m (H: 0,33 e M: 0,43 mlO2×kg-1×m-1, P=0,741) and in 200m (H: 0,24 e M: 0,31 mlO2×kg-1×m-1, P=0,948). During performance at distances of 50, 100 and 200 meters, the activation and contribution profiles of each energy metabolism has the highest absolute (mlO2×kg-1) alactic rate in men, when compared to activation in women, which demonstrate performance with lactic predominance at distances. Differences in energy production between the sexes show different values only for the production in 50 m (P = 0.039). Thus, women do not present restrictions for the anaerobic energetic supply, at supramaximum swimming speeds, when this demand is estimated by the traditional AOD method. However, the relative values of metabolic contribution tend not to be similar between men and women in the construction of the total anaerobic demand total (29,2% (50 m), 15,8% (100 m) and 29,3% (200 m) superior in men), caused by the greater activation of the alactic metabolism (64,7%, 47,4% e 60,9%) at each of these distances. This greater anaerobic alactic contribution in men may be an effect produced by muscle mass differences, suggesting the development of lean mass to improve performance in tasks with high anaerobic demand.
47

Physiological demands during rugby union matches and practice sessions

Smit, R.F. (Ruan Faure) 14 December 2011 (has links)
Research studies indicate that, by determining the physiological load placed on athletes during competitions, it can aid in the development of strength and conditioning programmes, according to the specific demands placed on athletes (Deutch et al., 1998; Kay&Gill, 2004). Physiological data, specifically on rugby union players, are furthermore limited and more information is needed (Banfi et al., 2006; Deutch et al., 2007). The aim of the study was to investigate the physiological demands of South African male U/21 club rugby players and to establish the correlation between physiological demands experienced during rugby games and practice sessions. Scientific methods to describe physiological demands in sport that are used are heart-rates and blood-lactate measurements (Eniseler, 2005). A group of U/21 rugby players (n=15) of the University of Pretoria (Tuks) rugby club participated in this study. Components that were tested included blood-lactate concentrations and heart-rates during rugby match and practice sessions. The data of the Tuks U/21 team was statistically analysed with descriptive statistics (means and standard deviations). Significant differences between match and practice sessions, at a p-value of P < 0.05, were determined by a dependent t-test. An independent t-test was used to determine significant differences between the forward and backs group (Thomas&Nelson, 2005). The results showed that statistically significant differences (p<0.05) were found between mean heart-rate in the rugby match (154.40 ±13.53) and practice sessions (138.33±4.81). No significant differences were found between peak lactate measurements in the match (5.39 ±2.44) and practice sessions (4.93±1.83). Between the forward and backs group no statistical significance could be found for average heart-rate and blood-lactate levels in practice sessions and the match. The findings of the present study indicate that rugby union matches for club level U/21 players are an intermittent type of activity, with both the use of aerobic and anaerobic energy systems. Additional research on more amateur rugby clubs is needed to extend the knowledge of club level coaches. / Dissertation (MA)--University of Pretoria, 2012. / Biokinetics, Sport and Leisure Sciences / unrestricted
48

Physiological responses in underwater sports. A systematic review of the diving response due to exercise performed in apnoea.David Esteve-

Esteve-Garde, David January 2021 (has links)
AbstractUnderwater sports such as artistic swimming and freediving, are characterized by periods of voluntary arrest of breathing, known as apnoea, while exercising. It is well known that apnoea leads to bradycardia and some other oxygen conserving responses, but little is known when exercise is conducted underwater, and the differences between exercise with intermittent and maximal apnoea periods. This review aims to understand and compare the physiological responses of the exercise performed underwater and the effect of the diving reflex in the heart rate, blood lactate, arterial pressure, arterial oxygen saturation and oxygen uptake, in different types of apnoea. A systematic review was conducted, searching studies in five scientific databases, according to specific criteria. 14 articles were selected for the analysis, using the method called PRISMA with systematic research, including just articles where trials were performed underwater. Artistic swimming and depth modalities of freediving are perceived as high intensity exercise. Blood lactate concentration (BLa), heart rate peak (HRpeak) and mean arterial pressure (MAP), depend more on exercise intensity, whereas arterial oxygen saturation (SaO2) and minimum heart rate (HRmin) is more related to apnoea duration. The diving response is more pronounced in freediving depth modalities due to impossibility of breathing. High intensity exercise mildly counteracts the diving reflex due to muscular and oxygen demands. Further investigation is needed in underwater sports, and physiological measurements should be performed according to a general consensus among researchers in order to avoid wide ranges of values in trial outcomes.
49

Substrate Utilization at Steady State Treadmill Walking with and without Blood Flow Restriction

Chen, Ge January 2018 (has links)
No description available.
50

Spirulina e exercício na recuperação de ratos submetidos à desnutrição protéica

Voltarelli, Fabricio Azevedo [UNESP] 02 December 2008 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:30:52Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-12-02Bitstream added on 2014-06-13T21:01:29Z : No. of bitstreams: 1 voltarelli_fa_dr_rcla.pdf: 9882732 bytes, checksum: 67c1cebc0d3bdc482da98a6519bf793b (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A desnutrição protéica é, ainda, hoje, grave problema médico-social nos países em desenvolvimento. Assim, é de grande interesse o desenvolvimento de procedimentos mais efetivos no seu tratamento. Isso inclui o emprego do exercício físico bem como de novas fontes de proteína na alimentação. O presente estudo visou avaliar os efeitos da spirulina como fonte protéica, associada ou não ao exercício físico, sobre o crescimento e o metabolismo protéico muscular de ratos em recuperação da desnutrição protéica. Foram utilizados ratos Wistar, jovens (30 dias), separados nos seguintes grupos, de acordo com a fonte e a quantidade de proteína na dieta: I- Caseína 17% dos 30 aos 150 dias de idade; II- Spirulina 17% dos 30 aos 150 dias de idade; III- Caseína 6% dos 30 aos 150 dias de idade; IV- Caseína 6% dos 30 aos 90 dias e Spirulina 17% dos 91 aos 150 dias de idade; V- Caseína 6% dos 30 aos 90 dias e Caseína 17% dos 91 aos 150 dias de idade. Aos 91 dias, metade dos animais de cada grupo foi submetida ao treinamento físico de natação, 1 hora/dia, 5 dias/semana, durante 8 semanas, com sobrecarga equivalente à transição metabólica aeróbio/anaeróbio determinada pelo teste do lactato mínimo. No músculo sóleo foram determinados peso e teores de proteína total e de DNA para inferir sobre o crescimento. Como índices do metabolismo protéico muscular, foram avaliadas as taxas de síntese (incorporação de 14C fenilalanina) e degradação (liberação de tirosina) de proteínas bem como a expressão da proteína miosina (western blotting). A spirulina provou ser uma fonte protéica adequada para animais submetidos ou não à desnutrição... / As we enter the 21st century and the new millennium, malnutrition remains the single most important factor impairing health and productivity of large human populations, mainly in the developing countries. For this reason, the exploration of alternative alimentary protein sources became a matter of generalized interest and may be, or not, associated to physical exercise. The present study verified the effects of the blue green alga spirulina as the dietary source of protein, associated or not to physical exercise, on growing and protein metabolism in skeletal muscle of young rats recovering from malnutrition. Young male wistar rats were separated into groups, according to diet protocol: Casein 6% from 30 to 150 days old; Spirulina 17% from 30 to 150 days; Casein 17% from 30 to 150 days; Casein 6% from 30 to 90 days and Spirulina 17% from 91 to 150 days and Casein 6% from 30 to 90 days and Casein 17% from 91 to 150 days. At 91 days, 50% of the animals of each group was submitted to swimming physical training, 1 hour/day, 5 days/week, during 8 weeks, supporting overload equivalent to aerobic/anaerobic metabolic transition determined by lactate minimum test. Spirulina proved to be an adequate protein source for animals submitted or not to protein malnutrition. This quality could be demonstrated by the maintenance of body length and weight of young animals fed the balanced diet containing spirulina. Considering the analysis of the muscle protein metabolism, the rates of protein synthesis and the expression... (Complete abstract click electronic access below)

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