Association Between Hematological Parameters and Iron Metabolism Response After Marathon Race and ACTN3 Genotype.

α-Actinin-3 (ACTN3 R577X, rs.1815739) polymorphism is a genetic variation that shows the most consistent influence on metabolic pathway and muscle phenotype. XX genotype is associated with higher metabolic efficiency of skeletal muscle; however, the role of ACTN3 polymorphism in oxygen transport and utilization system has not yet been investigated. Therefore, the aim of this study was to determine the influence of ACTN3 polymorphisms on hematological and iron metabolism response induced by marathon race. Eighty-one Brazilian amateur male endurance runners participated in the study. Blood samples and urine were collected before; immediately after; and 1, 3, and 15 days after the marathon race. Urine, hematological parameters, iron metabolism, and ACTN3 genotyping analyses were performed. The marathon race induced a decrease in erythrocytes, Hb, and Ht, and an increase in hematuria, creatinine, myoglobin, red cell distribution width, mean corpuscular hemoglobin concentration, mean corpuscular hemoglobin, direct and indirect bilirubin and erythropoietin. Moreover, an elevation immediately or 1 day after the marathon race follows a reduction 3 or 15 days after the marathon race were observed on transferrin saturation and iron and transferrin levels. Hematological parameters and iron metabolism changes induced by marathon race were not observed in XX genotypes. Hematuria and decreased erythrocytes, Hb, Ht, and iron and transferrin levels were observed only in RR and/or RX genotypes but not in XX genotypes. The percentage of runners with hematuria, leukocyturia, iron deficiency, creatinine, myoglobin, and bilirubin imbalance was higher in RR compared to XX genotypes. ACTN3 polymorphism is associated with iron metabolism and hematological responses after endurance exercise. Despite these results being based on a small sample, they highlight a protective role of the XX genotype on hematological and renal changes induced by long-distance exercise. Therefore, these findings should be further replicated.

Reduction in Post-Marathon Peak Oxygen Consumption: Sign of Cardiac Fatigue in Amateur Runners?

BACKGROUND: Prolonged aerobic exercise, such as running a marathon, produces supraphysiological stress that can affect the athlete's homeostasis. Some degree of transient myocardial dysfunction ("cardiac fatigue") can be observed for several days after the race. OBJECTIVE: To verify if there are changes in the cardiopulmonary capacity, and cardiac inotropy and lusitropy in amateur marathoners after running a marathon. METHODS: The sample comprised 6 male amateur runners. All of them underwent cardiopulmonary exercise testing (CPET) one week before the São Paulo Marathon, and 3 to 4 days after that race. They underwent echocardiography 24 hours prior to and immediately after the marathon. All subjects were instructed not to exercise, to maintain their regular diet, ingest the same usual amount of liquids, and rest at least 8 hours a day in the period preceding the CPET. RESULTS: The athletes completed the marathon in 221.5 (207; 250) minutes. In the post-marathon CPET, there was a significant reduction in peak oxygen consumption and peak oxygen pulse compared to the results obtained before the race (50.75 and 46.35 mL.kg-1 .min-1; 19.4 and 18.1 mL.btm, respectively). The echocardiography showed a significant reduction in the s' wave (inotropic marker), but no significant change in the E/e' ratio (lusitropic marker). CONCLUSIONS: In amateur runners, the marathon seems to promote changes in the cardiopulmonary capacity identified within 4 days after the race, with a reduction in the cardiac contractility. Such changes suggest that some degree of "cardiac fatigue" can occur.

Association between hematological parameters and iron metabolism response after marathon race and ACTN3 genotype

αlpha-Actinin-3 (ACTN3 R577X, rs.1815739) polymorphism is a genetic variation that shows the most consistent influence on metabolic pathway and muscle phenotype. XX genotype is associated with higher metabolic efficiency of skeletal muscle; however, the role of ACTN3 polymorphism in oxygen transport and utilization system has not yet been investigated. Therefore, the aim of this study was to determine the influence of ACTN3 polymorphisms on hematological and iron metabolism response induced by marathon race. Eighty-one Brazilian amateur male endurance runners participated in the study. Blood samples and urine were collected before; immediately after; and 1, 3, and 15 days after the marathon race. Urine, hematological parameters, iron metabolism, and ACTN3 genotyping analyses were performed. The marathon race induced a decrease in erythrocytes, Hb, and Ht, and an increase in hematuria, creatinine, myoglobin, red cell distribution width, mean corpuscular hemoglobin concentration, mean corpuscular hemoglobin, direct and indirect bilirubin and erythropoietin. Moreover, na elevation immediately or 1 day after the marathon race follows a reduction 3 or 15 days after the marathon race were observed on transferrin saturation and iron and transferrin levels. Hematological parameters and iron metabolism changes induced by marathon race were not observed in XX genotypes. Hematuria and decreased erythrocytes, Hb, Ht, and iron and transferrin levels were observed only in RR and/or RX genotypes but not in XX genotypes. The percentage of runners with hematuria, leukocyturia, iron deficiency, creatinine, myoglobin, and bilirubin imbalance was higher in RR compared to XX genotypes. ACTN3 polymorphism is associated with iron metabolism and hematological responses after endurance exercise. Despite these results being based on a small sample, they highlight protective role of the XX genotype on hematological and renal changes induced by long-distance exercise. Therefore, these findings should be further replicated.(AU)

Reduction in Post-Marathon Peak Oxygen Consumption: Sign of Cardiac Fatigue in Amateur Runners? / Redução no Consumo de Oxigênio Pico Pós Maratona: Sinal de Fadiga Cardíaca em Corredores Amadores?

Abstract Background: Prolonged aerobic exercise, such as running a marathon, produces supraphysiological stress that can affect the athlete's homeostasis. Some degree of transient myocardial dysfunction ("cardiac fatigue") can be observed for several days after the race. Objective: To verify if there are changes in the cardiopulmonary capacity, and cardiac inotropy and lusitropy in amateur marathoners after running a marathon. Methods: The sample comprised 6 male amateur runners. All of them underwent cardiopulmonary exercise testing (CPET) one week before the São Paulo Marathon, and 3 to 4 days after that race. They underwent echocardiography 24 hours prior to and immediately after the marathon. All subjects were instructed not to exercise, to maintain their regular diet, ingest the same usual amount of liquids, and rest at least 8 hours a day in the period preceding the CPET. Results: The athletes completed the marathon in 221.5 (207; 250) minutes. In the post-marathon CPET, there was a significant reduction in peak oxygen consumption and peak oxygen pulse compared to the results obtained before the race (50.75 and 46.35 mL.kg-1 .min-1; 19.4 and 18.1 mL.btm, respectively). The echocardiography showed a significant reduction in the s' wave (inotropic marker), but no significant change in the E/e' ratio (lusitropic marker). Conclusions: In amateur runners, the marathon seems to promote changes in the cardiopulmonary capacity identified within 4 days after the race, with a reduction in the cardiac contractility. Such changes suggest that some degree of "cardiac fatigue" can occur.

Resumo Fundamento: O exercício aeróbico prolongado, como correr uma maratona, produz um estresse suprafisiológico que pode ter impacto na homeostase do atleta. Algum grau de disfunção miocárdica transitória ("fadiga cardíaca") pode ser observado ao longo de vários dias após a prova. Objetivos: Verificar se ocorrem alterações na capacidade cardiopulmonar, no inotropismo e no lusitropismo cardíaco de maratonistas amadores após a realização de uma maratona. Métodos: A amostra foi composta por 6 corredores amadores masculinos. Todos realizaram teste cardiopulmonar de exercício (TCPE) uma semana antes da Maratona de São Paulo e 3 a 4 dias após a mesma. Realizaram ecocardiograma 24 horas antes e imediatamente após a prova. Todos foram orientados a não se exercitar, manter dieta regular, ingerir a mesma quantidade habitual de líquidos e descansar pelo menos 8 horas ao dia no período anterior ao TCPE. Resultados: Os atletas completaram a maratona em 221,5 (207; 250) minutos. No TCPE pós-maratona, ocorreu redução significativa no consumo de oxigênio e no pulso de oxigênio de pico em relação àqueles obtidos antes da prova (50,75 e 46,35 ml.kg-1.min-1; 19,4 e 18,1 ml.btm, respectivamente). Ao ecocardiograma, encontramos redução significativa na onda s' (marcador do inotropismo). A relação E/e' não apresentou alteração significativa após a maratona (marcador do lusitropismo). Conclusões: Em atletas amadores, a maratona parece promover alterações na capacidade cardiopulmonar identificadas pelo menos em até 4 dias após a prova, com redução na contratilidade e, portanto, no inotropismo cardíaco. Tais modificações sugerem que algum grau de "fadiga cardíaca" possa ocorrer.

Alteração de biomarcadores de lesão miocárdica em atletas após a Maratona Internacional de São Paulo / Changes in biomarkers of myocardial lesion in runners after the São Paulo International Marathon / Alteración de biomarcadores de lesión miocárdica en atletas después de Maratón Internacional de San Pablo

INTRODUÇÃO: Apesar de a prática regular de exercício físico reduzir o risco de doença cardiovascular, estudos recentes têm documentado elevações em biomarcadores relacionados com danos cardíacos após exercícios prolongados em indivíduos aparentemente saudáveis. OBJETIVO: Investigar as alterações nos níveis de brain natriuretic peptide (BNP) e troponina T cardíaca (cTnT) em atletas amadores após uma maratona, assim como verificar as possíveis relações entre as alterações, antes e depois da prova, apresentada pelos dois biomarcadores e variáveis do teste cardiopulmonar. MÉTODOS: Estudamos 38 atletas do sexo masculino (40,9 ± 6,29 anos) antes e depois da Maratona Internacional de São Paulo, SP, Brasil. Foram realizadas coletas de sangue na veia antecubital para mensurar os biomarcadores cardíacos, cTnT e BNP 24h antes, imediatamente após e 24h após a maratona. Foi realizado teste cardiopulmonar máximo nas três semanas que antecederam a prova. RESULTADOS: Os valores de BNP e cTnT aumentaram imediatamente após a maratona (p<0,001) quando comparados com os valores basais. No terceiro momento (24h) os valores de troponina tiveram uma redução significativa caracterizando um retorno aos valores basais. Não encontramos correlação entre idade e variáveis referentes a intensidade da maratona, porém encontramos correlação dos biomarcadores com o tempo de conclusão da maratona. CONCLUSÃO: Diferentes causas de liberação podem ser assumidas para cTnT e BNP e, neste caso, parecem não refletir dano miocárdico devido ao comportamento da curva destes marcadores, além de não haver relação entre a liberação dos dois biomarcadores. .

INTRODUCTION: Although the practice of physical exercises reduces the cardiovascular risk, recent studies have documented elevations in cardiac injury biomarkers after prolonged exercises in apparently healthy individuals. OBJECTIVE: We aimed to investigate the changes in brain natriuretic peptide (BNP) and cardiac troponin T (cTnT) levels after a marathon, and the correlation of these biomarkers and the variables of cardiopulmonary test. METHODS: We studied 38 male athletes (40.9 ± 6.29 years old) participants at the São Paulo International Marathon, SP, Brasil. Blood collections were performed to measure cTnT and BNP 24h before, immediately after and 24h after the marathon. Cardiopulmonary test was performed in the three weeks preceding the marathon. RESULTS: BNP and cTnT values increased significantly after the marathon (p<0.001). In the third moment (24h) the troponin values returned to the baseline values. We found no correlation between age and variables of the marathon, however, we did find a correlation between the biomarkers and time to complete the marathon. CONCLUSION: Various causes of release may be presumed for cTnT and BNP, however, they do not seem to reflect into myocardial injury, and there is no relationship between the releases of the two biomarkers. .

INTRODUCCIÓN: A pesar de que la práctica regular de ejercicio reduce el riesgo de enfermedad cardiovascular, estudios recientes han documentado elevaciones en biomarcadores relacionados con daños cardiacos después de ejercicios prolongados en individuos aparentemente saludables. OBJETIVO: Investigar las alteraciones en los niveles de BNP y troponina T cardiaca (cTnT) en atletas amateur después de maratón, así como verificar las posibles relaciones entre las alteraciones, antes y después de la prueba, presentada por dos biomarcadores y variables del test cardiopulmonar. MÉTODOS: Estudiamos 38 atletas del sexo masculino (40,9±6,29 años) antes y después de la Maratón Internacional de São Paulo, SP, Brasil. Fueron realizadas colectas de sangre en la vena antecubital para medir los biomarcadores cardiacos, cTnT y BNP, 24 horas antes, inmediatamente y 24 horas después de la Maratón. Fue realizado test cardiopulmonar máximo en las tres semanas que antecedieron a la maratón. RESULTADOS: Los valores de BNP y cTnT aumentaron inmediatamente después de la maratón (p<0,001) cuando comparados con los valores basales. En el tercer momento (24h) los valores de troponina tuvieron una reducción significativa caracterizando un retorno a los valores basales. No encontramos correlación entre edad y variables referentes a intensidad de la maratón, sin embargo encontramos correlación de los biomarcadores con el tiempo de conclusión de la maratón. CONCLUSIÓN: Diferentes causas de liberación pueden ser asumidas para cTnT y BNP y, en este caso, parecen no reflejar daño miocárdico debido al comportamiento de la curva de estos marcadores, además de no haber relación entre la liberación de los dos biomarcadores. .