The primary purpose of this doctoral dissertation was to investigate the effect of body temperature responses at physiologically relevant sites during an incremental exercise test on the phenomenon of exercise-induced hypoxemia (EIH). This phenomenon has been considered as an important limitation to physical performance with a prevalence of ~50 % in trained male athletes, but described in both sexes, across the range of both age and physical fitness in more recent literature. Previously this phenomenon has been described as a decrement in both arterial oxygen partial pressure (PaO₂) and oxy-haemoglobin saturation (SaO₂or SpO₂) with, particularly important for PaO₂, a lack of or inappropriate correction made for the change in body temperature during intense exercise. The initial study of this thesis determined the thermal response within the body at physiologically relevant sites measured simultaneously during an incremental exercise test. The results demonstrated the inadequacy of rectal temperature as an indicator of the acute temperature changes occurring during an incremental exercise test due to its slow response rate and relative thermal inertia. Radial arterial blood and oesophageal temperatures were shown to behave almost identically during the exercise test, albeit with an offset of approximately 1.3ºC, and were considered much more appropriate and relevant indicators of thermal changes during exercise. As an extension of the initial work active muscle temperature (vastus lateralis) was measured during the exercise test, demonstrating a significantly lower resting temperature than the oft-reported “core” temperatures (rectal and oesophageal) as well as a significantly greater increase in temperature in comparison to all other measurement sites. Overall, the results of this first study indicated that the physiologically relevant temperatures measured at the oesophageal and muscle sites differed markedly to the outdated rectal temperature measurement site and should be used as measures of thermal response when evaluating oxygen loading (oesophageal) or unloading (active muscle). Utilising the definition of EIH as a decrease in PaO₂ of ≥ 10 mmHg, the effect of temperature correcting PaO₂ was evaluated in the second study. Arterial blood gases measured simultaneously to the temperature measurements during the incremental exercise test were adjusted for the temperature changes at each site (every 1ºC increase in temperature will increase a PaO₂ value by ~5 mmHg). Whilst uncorrected PaO₂ values indicated an almost 100% prevalence of EIH in this group, oesophageal temperature corrected PaO₂ values decreased this prevalence to ~50% while muscle temperature corrections resolved all cases of EIH and demonstrated an HYPEROXAEMIA (i.e. the reverse of the well-established phenomenon) in the majority of subjects. Further investigation of arterial oxygen content during the exercise test indicates that there is no disruption in the delivery of oxygen to the active muscles and therefore any performance decrement should be attributed to another mechanism. Whilst the phenomenon of EIH is determined by the definition applied and the use of temperature corrections in the case of PaO₂, its reproducibility in a test-retest situation had not previously been determined. Utilising a subset of previously tested subjects, the reproducibility of both temperature and PaO₂ were determined with results indicating that the blood gas response was highly reproducible, especially the minimum PaO₂ value noted during each exercise test. However, comparing a more statistically relevant definition of a change in PaO₂ of ± 2 standard deviations from the mean resting PaO₂ to the previous delimiter of 10 mmHg indicated a lesser reproducibility of the prevalence of EIH. In summary, this thesis exposes the inadequacies of previous research into EIH with regard to the expected reproducibility of the phenomenon and the need to correctly adjust PaO₂ values for exercise-induce hyperthermia as well as demonstrating the difference in thermal responses to acute exercise in physiologically significant areas of the body. Furthermore, previously described correlations between the change in PaO₂ and VO₂ max were not evident in the subjects tested within this thesis, nor was there any indication of a diffusion limitation based on reduced pulmonary capillary transit time (by association with VO₂ max) or pulmonary oedema (rebuked by a rapid return of PaO₂ to above resting levels following exercise cessation). / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1320633 / Thesis (Ph.D.) -- University of Adelaide, School of Medicine, 2008

Träningsvärk efter fysisk aktivitet är ett välkänt fenomen. Vad som ligger bakomträningsvärkens effekter såsom smärta och nedsatt rörlighet är mindre välkänt. Träningsvärk, eller ”delayed onset muscle soreness” (DOMS), har i forskningenantagits bero på muskelskada och inflammation i skelettmusklerna efter att ovana ellerexcentriska övningar utförts. Försöken att lindra träningsvärkens effekter har varitmånga, t ex genom antiinflammatoriska läkemedel (NSAID). Syftet med dennasystematiska litteraturstudie var att svara på frågeställningen hur ibuprofen påverkarträningsvärk där hypotesen att ibuprofen skulle ha en dämpande effekt på träningsvärkantogs. Nio artiklar granskades för att besvara hypotesen utan att några slutsatser omibuprofens inverkan på träningsvärk kunde dras då resultaten pekade åt olika håll ochinga tendenser kunde observeras. Den slutsats som kunde dras utifrån litteraturstudienvar att ytterligare forskning på området är behövlig. Om studier inte kan visa att NSAIDdämpar träningsvärk så kan det ifrågasättas om inflammation är orsaken tillträningsvärken. Ytterligare studier på området är viktigt då NSAID är vanligtförekommande som smärtlindrande läkemedel samtidigt som det har biverkningar. Det finns också forskning som tyder på att NSAID kan ha negativ inverkan på de positivaeffekter som är av intresse i träningssammanhang.

No description available.

Após a realização de uma sessão de treinamento (ST) é comum a ocorrência do fenômeno denominado dano muscular induzido pelo exercício (DMIE), que se caracteriza por prejuizos a estrutura da fibra muscular, com ruptura de alguns sarcômeros, desordem miofibrilar e alargamento das linhas Z. Ainda em consequência ao DMIE, surgem alguns sintomas que são utilizados como marcadores indiretos: dor muscular de início tardio (DMIT), redução na produção de força, aumento de enzimas e proteínas na corrente sanguínea e inchaço. O presente estudo examinou os efeitos da suplementação nutricional a fim de minimizar os efeitos deletérios do DMIE em 3 experimentos. No 1° estudo, 36 indivíduos inexperientes em treinamento de força (TF) foram suplementados com: placebo (PLA, n=12, 50mg·kg-1 de carboidrato); leucina (LEU) baixa dose (LBD, n=12, 50mg·kg-1 de LEU + 50mg·kg-1 de carboidrato) e LEU alta dose (LAD, n=12, 250mg·kg-1 de LEU + 50mg·kg-1 de carboidrato) por 6 dias antecedentes a sessão de treinamento (ST), e nos 3 dias seguintes. Foi observada redução significante, p<0.05, na dor muscular de início tardio (DMIT) do peitoral por palpação, e alongamento nos momentos 48h, e 72h após a ST no grupo LBD comparado ao PLA. A redução no teste de 1 repetição máxima (1RM) apresentou significância no grupo PLA em todos momentos após ST. O aumento na atividade da creatina quinase (CK) foi significante no grupo PLA comparado ao LAD em 24h, 48h e 72h após a ST, enquanto o aumento da concentração de mioglobina (Mb) foi significante no grupo PLA comparado ao grupo LBD e LAD em 24h, 48h e 72h após a ST. O 2° estudo contou com a participação de 28 indivíduos com até 6 meses de experiência em TF. Os sujeitos foram suplementados com 3g de &beta;-hidroxi-&beta;-metilbutirato (HM) por 14 dias (H14, n=07); 7 dias (H07, n=07) e placebo por 14 dias (P14) ou 7 dias (P07, n=07) antecedentes a ST, e nos 3 dias seguintes. O aumento da DMIT por palpação e alongamento foi significante no grupo P14 comparado ao H14 em 24h (apenas alongamento), 48h e 72h após ST, ainda no momento 72h o grupo P07 era superior ao H07. A redução no teste de 1RM ocorreu nos 4 grupos imediatamente após, foi mantida em 24h após a ST nos grupos H14, H07 e P07, sem diferenças entre os grupos. O aumento na concentração de Mb foi significante no grupo P14 comparado ao grupo H14. No 3° estudo, 24 indivíduos experientes em TF foram suplementados com 7g de arginina (ARG, n=12) ou placebo (PLA, n=12, 7g carboidrato) 30 minutos pré-ST. O grupo PLA apresentou aumento significante na DMIT por palpação em 24h comparado ao grupo ARG. A redução no teste de 1RM alcançou significância apenas em 24h após a ST no grupo PLA, mas sem diferença entre os grupos. Os resultados do presente estudo permitem concluir que a suplementação nutricional implementada atenuou o comportamento de alguns marcadores indiretos DMIE, com maior efeito para a DMIT e parametros bioquímicos / After performing a training session (TS) is common the occurrence of the phenomenon called muscle damage induced by exercise (DMIE), which is characterized by damage to muscle fiber structure, breaking some sarcomeres, myofibrillar disorder and extension lines Z. As a consequence of DMIE, there are some symptoms that are measured as indirect markers: delayed onset muscle soreness (DOMS), reduction in strength production, increase of enzymes and proteins in the bloodstream, and swelling. The effect of nutritional interventions to minimize deleterious responses associated with exercise-induced muscle damage (EIMD) were investigated in 3 experiments. In study 1, 36 inexperienced subjects in resistance training (RT) were supplemented for 6 days prior to the training session (TS), and in the following 3 days with: placebo (PLA, n=12, 50mg·kg-1 of carbohydrate); leucine (LEU) low dose (LLD, n=12, 250mg·kg-1 LEU + 50mg·kg-1 + carbohydrate) and LEU high dose (LHD, n=12, 250mg·kg-1 LEU + 50mg·kg-1 + carbohydrate). There was a significant reduction (p <0.05) in delayed onset muscle soreness (DOMS), of the chest by palpation and stretching at 48h, after TS in the LLD group compared to PLA. A significant reduction in the one repetition maximum (1RM) test was observed in the PLA group at all times after TS. The increase in creatine kinase (CK) activity was significant in the PLA group compared to the LHD in 24h, 48h and 72h after TS, while the increase in myoglobin concentration (Mb) was significant in the PLA group compared to the LLD and LHD group in 24h, 48h, and 72h after TS. In study 2, 28 subjects with up to 6 months of RT experience were supplemented with 3g of &beta;-hydroxy-&beta;-methylbutyrate (HM&beta;) for 14 days (H14, n=7); for 7 days (H07, n=7), and placebo for 14 days (P14, n=7) or 7 days (P07, n=7) antecedent to ST, and in the next 3 days. The increase in DOMS by palpation and stretching was significant in the P14 group compared to H14 in 24h (stretching only), 48h and 72h after TS, yet at 72h the P07 group was higher than H07. The reduction in the 1RM test occurred in the 4 groups immediately after and maintained within 24h after TS in groups H14, H07 and P07, and there was no difference between groups. The increase in Mb concentration was significant in the P14 group compared to the H14 group. In study 3, 24 resistance-trained subjects were supplemented with 7g of arginine (ARG, n=12) or placebo (PLA, n=12, 7g of carbohydrate) 30 minutes pre- TS. The PLA group presented a significant increase in DOMS by palpation in 24h compared to the ARG group, and a significant reduction in the 1RM test only in 24h after ST in the PLA group, but without a significant difference between groups. The results of the present study suggest that the responses of indirect markers associated with EIMD were attenuated by nutritional interventions, with greater effect for DOMS and biochemical parameters

A prevalência de sintomas de asma, broncoespasmo induzido pelo exercício (BIE), hiperresponsividade brônquica (HRB) e alergia em atletas que praticam modalidades de alto rendimento e longa duração tem aumentado nas últimas décadas e tem sido estudada principalmente em atletas de inverno e nadadores. No entanto, a prevalência de sintomas de asma e alergia e os mecanismos inflamatórios envolvidos no BIE que ocorre em corredores de longa distância permanecem pouco conhecidos. Objetivos: O presente estudo tem como objetivo avaliar a prevalência de sintomas de asma e alergia em corredores de longa distância de elite e investigar os mecanismos inflamatórios envolvidos no BIE nos atletas sem histórico de asma. Casuística e Métodos: Este estudo foi realizado em duas fases: na Fase I, foi avaliada a prevalência de sintomas de asma e alergia em 201 corredores de longa distância, através da aplicação dos questionários ISAAC e AQUA©. Na Fase II, foram avaliados os mecanismos inflamatórios envolvidos no BIE de 40 corredores que não apresentaram sintomas de asma na Fase I e que foram selecionados aleatoriamente. Nesta fase, os atletas compareceram ao laboratório em três momentos, com intervalo máximo de duas semanas entre cada visita, e foram submetidos às seguintes avaliações 1º) escarro induzido e teste cardiopulmonar máximo, 2º) broncoprovocação por metacolina e, 3º) óxido nítrico no ar exalado (FeNO), metabólitos LTE4 e 9alfa, 11beta-PGF2 e teste de hiperventilação eucápnica voluntária (HEV). Resultados: A prevalência de sintomas de asma e alergia foi de 6,5% e 60,5%, respectivamente. Ao analisar as questões do AQUA©, observou-se alta frequência de sintomas de BIE (62,3%) e rinite (56,6%). Os sintomas de alergia não foram associados a variáveis como gênero, idade, experiência em corridas de longa distância, volume de treinamento semanal e desempenho em provas de meia maratona e maratona. Verificou-se ainda que a prevalência de BIE foi de 27,5%. Quando comparados os atletas BIE+ e BIE- não foram observadas diferenças nos valores de VEF1 absoluto, nas medidas antropométricas, nas características de treinamento e também no desempenho. Os atletas BIE+ relataram mais sintomas de alergia (p=0,03), se mostraram mais responsivos à metacolina (p=0,01), apresentaram maior porcentagem de eosinófilos no escarro (p=0,03) e níveis mais elevados de FeNO (p < 0,001*) quando comparados aos atletas BIE-. Os níveis urinários de LTE4 e 9alfa, 11beta-PGF2 basais e após 60 minutos do teste de HEV foram similares entre os grupos BIE+ e BIE-, no entanto, ao comparar os níveis destes mediadores antes e após o teste de HEV, observou-se uma diminuição nos níveis de LTE4, apenas nos atletas BIE- (p=0,04). Conclusões: Corredores de longa distância apresentam elevada prevalência de sintomas de alergia e BIE e baixa prevalência de sintomas de asma. Além disto, os atletas BIE+ referem mais sintomas de alergia, são mais hiperresponsivos à metacolina, apresentam um padrão inflamatório eosinofílico e elevados níveis de FeNO embora sem diferenças nos níveis basais dos metabólitos do mastócito / An increased prevalence of asthma and allergic symptoms, exercise-induced bronchoconstriction (EIB) and bronchial hyperresponsiveness (BHR) has been observed in elite and endurance athletes, especially winter sports athletes and swimmers. However, the occurrence of allergy symptoms and the inflammatory mechanisms involved in the EIB that occurs in long distance runners remains poorly known. Objectives: the aims of the present study were to assess the prevalence of symptoms of asthma and allergy in long distance runners and to investigate possible inflammatory mediators involved in the EIB that occurs in those without asthma history. Methods: This cross sectional study was performed in two phases. In Phase I, the prevalence of symptoms of asthma and allergy was assessed in 201 long distance runners using ISAAC and AQUA© questionnaires. In Phase II, 40 athletes were randomly selected among those who did not present asthma history and they performed the following measurements: induced sputum, cardiopulmonary exercise testing, methacholine bronchoprovocation challenge, exhaled nitric oxide (FeNO), urinary collection to quantify LTE4 and 9alfa, 11beta-PGF2 metabolites and eucapnic voluntary hyperventilation test (EVH). Results: The prevalence of asthma and allergy symptoms was 6.5% and 60.5%, respectively. In addition, we observed a high frequency of EIB symptoms (62.3%) and rhinitis (56.6%). Allergy symptoms were not associated with anthropometric characteristics, running experience, weekly training volume and best half-marathon and marathon performance. The prevalence of EIB was 27.5% and no difference in baseline lung function, anthropometric data as well as training and performance characteristics was observed between athletes with (EIB+) and without (EIB-) EIB. EIB+ athletes reported more allergy symptoms (p=0.03) and were more resposive to methacholine (p=0.01) than EIB- athletes. A higher percentage of eosinophils in the induced sputum (p=0.03) and levels of FeNO (p < 0.001*) were observed in EIB+ athletes. However, there was no difference in the urinary levels of LTE4 and 9alfa, 11beta-PGF2 either at baseline or after EVH test. Conclusions: Long distance runners have a high prevalence of allergy symptoms and EIB and a low prevalence of asthma symptoms. Moreover, EIB+ athletes report more symptoms of allergy and present airway hyperresponsiveness, eosinophilic inflammation and increased levels of exhaled nitric oxide, without difference in the baseline levels of mast cell metabolites

Made available in DSpace on 2016-06-02T20:18:24Z (GMT). No. of bitstreams: 1 6321.pdf: 1608143 bytes, checksum: 79020037f93ef260d48c286f33c9f952 (MD5) Previous issue date: 2014-08-29 / Universidade Federal de Minas Gerais / Asthma is a chronic disease, with periods of exacerbation and worsening of airflow obstruction and may be triggered by various stimuli, including exercise, and is associated with dysfunction of the autonomic nervous system (ANS). In this context, two studies were conducted to assess adjustments of ANS in asthmatic volunteers in different situations. The first study was entitled: Increased sympathetic modulation and decreased response of the heart rate variability response in controlled asthma , was designed to evaluate the adjustments of indices of autonomic modulation of heart rate (HR) at rest in supine and seated positions and during the respiratory sinus arrhythmia maneuver (M-RSA). The assessment of 12 asthmatic volunteers included pulmonary function tests and measures of heart rate variability (HRV). The results suggest that in asthma appears to be an association of airflow obstruction with reduced total variability, and in addition, to postural change seems to be reduced adjustment of the sympathetic nervous system in asthmatic women. The second study entitled: Airway responsiveness at exercise recovery and adjustments of heart rate variability at rest and exercise in controlled asthma , evaluated the adjustments of cardiac autonomic modulation during exercise its association with the exercise induced bronchoconstriction. Sixteen asthmatics volunteers underwent constant speed exercise test, forced vital capacity maneuver before and after exercise testing and register of HR and R-R intervals. With this second study, it can conclude that in asthmatics, even with controlled disease, injury presents postural and autonomic adjustments during the year and reduced complexity of dynamical systems of HRV during exercise. / A asma é uma doença crônica, com períodos de exacerbação e piora da obstrução ao fluxo aéreo, podendo ser desencadeada por vários estímulos, incluindo o exercício, e está associada a disfunções do sistema nervoso autonômico (SNA). Nesse contexto, foram realizados dois estudos para avaliação dos ajustes do SNA em voluntários asmáticos, em diferentes situações. O primeiro estudo intitulado: Elevada modulação simpática e atenuada resposta da variabilidade da frequência cardíaca na asma controlada , teve como objetivo avaliar os ajustes dos índices de modulação autonômica da frequência cardíaca (FC) em repouso, na manobra de mudança postural e durante a manobra de acentuação da arritmia sinusal respiratória. A avaliação de 12 voluntárias asmáticas, incluiu prova de função pulmonar e medidas da variabilidade da frequência cardíaca (VFC) nas diferentes posições e durante a manobra de acentuação da arritmia sinusal respiratória. Os resultados sugerem que na asma parece haver associação da obstrução ao fluxo aéreo com reduzida variabilidade total, e além disso, frente à mudança postural parece haver reduzido ajuste do sistema nervoso simpático em mulheres asmáticas. Diante destes resultados, objetivamos avaliar a VFC também durante o exercício em voluntários asmáticos. Sendo assim, o segundo estudo intitulado: Responsividade das vias aéreas na recuperação do exercício e os ajustes da variabilidade da frequência cardíaca em repouso e durante o exercício em asmáticos controlados , avaliou os ajustes da modulação autonômica cardíaca durante o exercício e sua associação com a presença de broncoconstrição induzia pelo exercício (BIE). Dezesseis voluntários com asma foram submetidos a um teste de exercício de carga constante em esteira, manobras de capacidade vital forçada antes e após o teste de exercício e registro da FC e dos intervalos R-R. Com este segundo estudo, pode-se concluir que em asmáticos, mesmo com a doença controlada, há prejuízo nos ajustes autonômicos posturais e durante o exercício, bem como reduzida complexidade dos sistemas dinâmicos de VFC durante o exercício.

A prevalência de sintomas de asma, broncoespasmo induzido pelo exercício (BIE), hiperresponsividade brônquica (HRB) e alergia em atletas que praticam modalidades de alto rendimento e longa duração tem aumentado nas últimas décadas e tem sido estudada principalmente em atletas de inverno e nadadores. No entanto, a prevalência de sintomas de asma e alergia e os mecanismos inflamatórios envolvidos no BIE que ocorre em corredores de longa distância permanecem pouco conhecidos. Objetivos: O presente estudo tem como objetivo avaliar a prevalência de sintomas de asma e alergia em corredores de longa distância de elite e investigar os mecanismos inflamatórios envolvidos no BIE nos atletas sem histórico de asma. Casuística e Métodos: Este estudo foi realizado em duas fases: na Fase I, foi avaliada a prevalência de sintomas de asma e alergia em 201 corredores de longa distância, através da aplicação dos questionários ISAAC e AQUA©. Na Fase II, foram avaliados os mecanismos inflamatórios envolvidos no BIE de 40 corredores que não apresentaram sintomas de asma na Fase I e que foram selecionados aleatoriamente. Nesta fase, os atletas compareceram ao laboratório em três momentos, com intervalo máximo de duas semanas entre cada visita, e foram submetidos às seguintes avaliações 1º) escarro induzido e teste cardiopulmonar máximo, 2º) broncoprovocação por metacolina e, 3º) óxido nítrico no ar exalado (FeNO), metabólitos LTE4 e 9alfa, 11beta-PGF2 e teste de hiperventilação eucápnica voluntária (HEV). Resultados: A prevalência de sintomas de asma e alergia foi de 6,5% e 60,5%, respectivamente. Ao analisar as questões do AQUA©, observou-se alta frequência de sintomas de BIE (62,3%) e rinite (56,6%). Os sintomas de alergia não foram associados a variáveis como gênero, idade, experiência em corridas de longa distância, volume de treinamento semanal e desempenho em provas de meia maratona e maratona. Verificou-se ainda que a prevalência de BIE foi de 27,5%. Quando comparados os atletas BIE+ e BIE- não foram observadas diferenças nos valores de VEF1 absoluto, nas medidas antropométricas, nas características de treinamento e também no desempenho. Os atletas BIE+ relataram mais sintomas de alergia (p=0,03), se mostraram mais responsivos à metacolina (p=0,01), apresentaram maior porcentagem de eosinófilos no escarro (p=0,03) e níveis mais elevados de FeNO (p < 0,001*) quando comparados aos atletas BIE-. Os níveis urinários de LTE4 e 9alfa, 11beta-PGF2 basais e após 60 minutos do teste de HEV foram similares entre os grupos BIE+ e BIE-, no entanto, ao comparar os níveis destes mediadores antes e após o teste de HEV, observou-se uma diminuição nos níveis de LTE4, apenas nos atletas BIE- (p=0,04). Conclusões: Corredores de longa distância apresentam elevada prevalência de sintomas de alergia e BIE e baixa prevalência de sintomas de asma. Além disto, os atletas BIE+ referem mais sintomas de alergia, são mais hiperresponsivos à metacolina, apresentam um padrão inflamatório eosinofílico e elevados níveis de FeNO embora sem diferenças nos níveis basais dos metabólitos do mastócito / An increased prevalence of asthma and allergic symptoms, exercise-induced bronchoconstriction (EIB) and bronchial hyperresponsiveness (BHR) has been observed in elite and endurance athletes, especially winter sports athletes and swimmers. However, the occurrence of allergy symptoms and the inflammatory mechanisms involved in the EIB that occurs in long distance runners remains poorly known. Objectives: the aims of the present study were to assess the prevalence of symptoms of asthma and allergy in long distance runners and to investigate possible inflammatory mediators involved in the EIB that occurs in those without asthma history. Methods: This cross sectional study was performed in two phases. In Phase I, the prevalence of symptoms of asthma and allergy was assessed in 201 long distance runners using ISAAC and AQUA© questionnaires. In Phase II, 40 athletes were randomly selected among those who did not present asthma history and they performed the following measurements: induced sputum, cardiopulmonary exercise testing, methacholine bronchoprovocation challenge, exhaled nitric oxide (FeNO), urinary collection to quantify LTE4 and 9alfa, 11beta-PGF2 metabolites and eucapnic voluntary hyperventilation test (EVH). Results: The prevalence of asthma and allergy symptoms was 6.5% and 60.5%, respectively. In addition, we observed a high frequency of EIB symptoms (62.3%) and rhinitis (56.6%). Allergy symptoms were not associated with anthropometric characteristics, running experience, weekly training volume and best half-marathon and marathon performance. The prevalence of EIB was 27.5% and no difference in baseline lung function, anthropometric data as well as training and performance characteristics was observed between athletes with (EIB+) and without (EIB-) EIB. EIB+ athletes reported more allergy symptoms (p=0.03) and were more resposive to methacholine (p=0.01) than EIB- athletes. A higher percentage of eosinophils in the induced sputum (p=0.03) and levels of FeNO (p < 0.001*) were observed in EIB+ athletes. However, there was no difference in the urinary levels of LTE4 and 9alfa, 11beta-PGF2 either at baseline or after EVH test. Conclusions: Long distance runners have a high prevalence of allergy symptoms and EIB and a low prevalence of asthma symptoms. Moreover, EIB+ athletes report more symptoms of allergy and present airway hyperresponsiveness, eosinophilic inflammation and increased levels of exhaled nitric oxide, without difference in the baseline levels of mast cell metabolites

Após a realização de uma sessão de treinamento (ST) é comum a ocorrência do fenômeno denominado dano muscular induzido pelo exercício (DMIE), que se caracteriza por prejuizos a estrutura da fibra muscular, com ruptura de alguns sarcômeros, desordem miofibrilar e alargamento das linhas Z. Ainda em consequência ao DMIE, surgem alguns sintomas que são utilizados como marcadores indiretos: dor muscular de início tardio (DMIT), redução na produção de força, aumento de enzimas e proteínas na corrente sanguínea e inchaço. O presente estudo examinou os efeitos da suplementação nutricional a fim de minimizar os efeitos deletérios do DMIE em 3 experimentos. No 1° estudo, 36 indivíduos inexperientes em treinamento de força (TF) foram suplementados com: placebo (PLA, n=12, 50mg·kg-1 de carboidrato); leucina (LEU) baixa dose (LBD, n=12, 50mg·kg-1 de LEU + 50mg·kg-1 de carboidrato) e LEU alta dose (LAD, n=12, 250mg·kg-1 de LEU + 50mg·kg-1 de carboidrato) por 6 dias antecedentes a sessão de treinamento (ST), e nos 3 dias seguintes. Foi observada redução significante, p<0.05, na dor muscular de início tardio (DMIT) do peitoral por palpação, e alongamento nos momentos 48h, e 72h após a ST no grupo LBD comparado ao PLA. A redução no teste de 1 repetição máxima (1RM) apresentou significância no grupo PLA em todos momentos após ST. O aumento na atividade da creatina quinase (CK) foi significante no grupo PLA comparado ao LAD em 24h, 48h e 72h após a ST, enquanto o aumento da concentração de mioglobina (Mb) foi significante no grupo PLA comparado ao grupo LBD e LAD em 24h, 48h e 72h após a ST. O 2° estudo contou com a participação de 28 indivíduos com até 6 meses de experiência em TF. Os sujeitos foram suplementados com 3g de &beta;-hidroxi-&beta;-metilbutirato (HM) por 14 dias (H14, n=07); 7 dias (H07, n=07) e placebo por 14 dias (P14) ou 7 dias (P07, n=07) antecedentes a ST, e nos 3 dias seguintes. O aumento da DMIT por palpação e alongamento foi significante no grupo P14 comparado ao H14 em 24h (apenas alongamento), 48h e 72h após ST, ainda no momento 72h o grupo P07 era superior ao H07. A redução no teste de 1RM ocorreu nos 4 grupos imediatamente após, foi mantida em 24h após a ST nos grupos H14, H07 e P07, sem diferenças entre os grupos. O aumento na concentração de Mb foi significante no grupo P14 comparado ao grupo H14. No 3° estudo, 24 indivíduos experientes em TF foram suplementados com 7g de arginina (ARG, n=12) ou placebo (PLA, n=12, 7g carboidrato) 30 minutos pré-ST. O grupo PLA apresentou aumento significante na DMIT por palpação em 24h comparado ao grupo ARG. A redução no teste de 1RM alcançou significância apenas em 24h após a ST no grupo PLA, mas sem diferença entre os grupos. Os resultados do presente estudo permitem concluir que a suplementação nutricional implementada atenuou o comportamento de alguns marcadores indiretos DMIE, com maior efeito para a DMIT e parametros bioquímicos / After performing a training session (TS) is common the occurrence of the phenomenon called muscle damage induced by exercise (DMIE), which is characterized by damage to muscle fiber structure, breaking some sarcomeres, myofibrillar disorder and extension lines Z. As a consequence of DMIE, there are some symptoms that are measured as indirect markers: delayed onset muscle soreness (DOMS), reduction in strength production, increase of enzymes and proteins in the bloodstream, and swelling. The effect of nutritional interventions to minimize deleterious responses associated with exercise-induced muscle damage (EIMD) were investigated in 3 experiments. In study 1, 36 inexperienced subjects in resistance training (RT) were supplemented for 6 days prior to the training session (TS), and in the following 3 days with: placebo (PLA, n=12, 50mg·kg-1 of carbohydrate); leucine (LEU) low dose (LLD, n=12, 250mg·kg-1 LEU + 50mg·kg-1 + carbohydrate) and LEU high dose (LHD, n=12, 250mg·kg-1 LEU + 50mg·kg-1 + carbohydrate). There was a significant reduction (p <0.05) in delayed onset muscle soreness (DOMS), of the chest by palpation and stretching at 48h, after TS in the LLD group compared to PLA. A significant reduction in the one repetition maximum (1RM) test was observed in the PLA group at all times after TS. The increase in creatine kinase (CK) activity was significant in the PLA group compared to the LHD in 24h, 48h and 72h after TS, while the increase in myoglobin concentration (Mb) was significant in the PLA group compared to the LLD and LHD group in 24h, 48h, and 72h after TS. In study 2, 28 subjects with up to 6 months of RT experience were supplemented with 3g of &beta;-hydroxy-&beta;-methylbutyrate (HM&beta;) for 14 days (H14, n=7); for 7 days (H07, n=7), and placebo for 14 days (P14, n=7) or 7 days (P07, n=7) antecedent to ST, and in the next 3 days. The increase in DOMS by palpation and stretching was significant in the P14 group compared to H14 in 24h (stretching only), 48h and 72h after TS, yet at 72h the P07 group was higher than H07. The reduction in the 1RM test occurred in the 4 groups immediately after and maintained within 24h after TS in groups H14, H07 and P07, and there was no difference between groups. The increase in Mb concentration was significant in the P14 group compared to the H14 group. In study 3, 24 resistance-trained subjects were supplemented with 7g of arginine (ARG, n=12) or placebo (PLA, n=12, 7g of carbohydrate) 30 minutes pre- TS. The PLA group presented a significant increase in DOMS by palpation in 24h compared to the ARG group, and a significant reduction in the 1RM test only in 24h after ST in the PLA group, but without a significant difference between groups. The results of the present study suggest that the responses of indirect markers associated with EIMD were attenuated by nutritional interventions, with greater effect for DOMS and biochemical parameters

Introduktion: En minskad smärtkänslighet som uppkommer under eller efter träning är ett fenomen som kallas för träningsinducerad hypoalgesi (Exercise-induced hypoalgesia, EIH). Metodiken för studier om EIH är mångsidig och resultaten har därför inte alltid varit samstämmiga. Aerob träning har visat sig kunna höja smärttröskeln och minska smärtkänsligheten hos individer. Forskningen om aerob kapacitet och dess samband med EIH hos friska individer är bristfällig.  Syfte: Att undersöka effekten av ett aerobt träningspass på smärtkänslighet samt att analysera sambandet mellan aerob kapacitet och smärtkänslighet hos friska individer.  Metod: Ett submaximalt cykeltest utfördes av 19 friska individer mellan 20-38 år, i syfte att estimera maximal syreupptagningsförmåga (VO2max). Detta var följt av ett EIH-test för att undersöka eventuell höjning av trycksmärttröskeln (Pressure pain threshold, PPT). EIH-testet bestod av ett 15 minuters cykelpass på 75% av VO2max där mätning av PPT utfördes på arbetande (ben) respektive vilande (arm) muskulatur, direkt före och direkt efter träningspasset.   Resultat: En signifikant ökning av PPT för arbetande muskulatur (p=0,018) påvisades efter träning. Ingen signifikant förändring av PPT påvisades för vilande muskulatur (p=0,052). Det observerades inget signifikant samband mellan maximal syreupptagningsförmåga (VO2max) och EIH-effekt (ben, p= 0,860; arm, p= 0,942).  Konklusion: Ett högintensivt aerobt cykelpass gav en signifikant höjning av PPT för den arbetande muskulaturen. Inget signifikant samband påvisades mellan VO2max och EIH-effekt (differensen mellan PPT direkt efter och direkt före träning). Ytterligare studier med ett högre deltagarantal behövs för att undersöka detta samband mer ingående samt för att underlätta jämförelser mellan studier.

Much of the impetus for this research can be attributed to Kenneth W. Hinchcliff, who has studied exercise-induced pulmonary haemorrhage (EIPH) extensively. This thesis focused on EIPH in Thoroughbred racehorses competing in South Africa. Using tracheobronchoscopy, the prevalence and severity of EIPH and the association with racing performance was determined. Thereafter, the prevalence of other respiratory tract disorders and their association with racing performance is reported. This is followed by a study assessing interobserver variability using grading systems in the detection of respiratory tract disorders. Finally, there is a report on the immunopathogenesis of EIPH. Using tracheobronchoscopy after racing, the prevalence and severity of EIPH was assessed in 1,005 racehorses competing at high altitude (> 1,400 meters above sea level) and at sea level in a racing jurisdiction that does not allow the use of furosemide and nasal dilator strips. The prevalence and severity of EIPH was affected by altitude as racing at sea level was associated with a higher prevalence and greater severity of EIPH. Results also suggested that EIPH was associated with superior performance in South African Thoroughbred racehorses. Upper and lower respiratory tract disorders identified following tracheobronchoscopic examination included left arytenoid asymmetry, left laryngeal hemiplegia, epiglottic deformity, epiglottic entrapment, subepiglottic cysts, dorsal displacement of the soft palate, pharyngeal lymphoid hyperplasia (PLH), laryngeal and tracheal dirt, tracheal mucous (TM), tracheal stenosis and tracheal cartilage ring spikes in Thoroughbred racehorses after racing. Overall, there was a low prevalence of grade 2 and 3 arytenoid cartilage asymmetry, left laryngeal hemiplegia, epiglottic entrapment, subepiglottic cysts and epiglottic deformity, while more severe grades of PLH, laryngeal debris, tracheal debris, TM and tracheal cartilage ring spikes had a higher prevalence. An association with sex was identified as tracheal cartilage ring spikes occurred more often in male racehorses. Superior racing performance was identified in racehorses with grade 3 tracheal mucous and tracheal cartilage ring spikes. Endoscopic grading of EIPH, PLH, arytenoid cartilage movement (ACM), and TM was performed by 3 observers that were blinded to each racehorse’s identity and race day performance using previously established grading criteria. Excellent interobserver reliability was seen using the EIPH grading system, while the weighted kappa for PLH, ACM and TM was lower. The study demonstrated sufficient reliability for the use of the EIPH, PLH, ACM and TM grading systems in racehorses competing in South Africa. The study concluded that tracheobronchoscopy seemed to be a practical screening technique that may have prognosticative validity and clinical dependability and that would allow safe and quick assessment of the respiratory tract of a large number of racehorses in field conditions. Venous blood was collected from 10 horses in each EIPH grade classification (grade 0 to 4) following tracheobronchoscopic examinations for the determination of the presence and severity of EIPH. Following RNA isolation and cDNA synthesis, real-time PCR was used to detect equine cytokine-specific mRNA for interleukin (IL) -1, -6, -10, interferon (INF) -ã, and tumor necrosis factor (TNF) -á. Results of this study indicated that increased IL-6, and -10 mRNA production was associated with more severe forms of EIPH. Also, there was greater expression of IL-6 mRNA at sea level and TNF-á mRNA at high altitude. This study concluded that although it was unclear whether the inflammatory response observed in the study was due to pre-existing pulmonary inflammation or as a direct consequence of pulmonary bleeding, the study demonstrated a systemic correlation to pulmonary inflammation. The research reported in this thesis has contributed substantially to the determination of the prevalence, severity and affect on racing performance of respiratory tract disorders in Thoroughbred racehorses competing in South Africa. Also, determination of an association between EIPH and inflammation at a molecular level may assist future researchers in anti-cytokine therapies which may help reduce the prevalence and severity of EIPH. / Thesis (PHD)--University of Pretoria, 2007. / Companion Animal Clinical Studies / unrestricted