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1.
Artigo em Inglês | MEDLINE | ID: mdl-33803383

RESUMO

Several anthropometric and performance parameters related to aerobic metabolism are associated with performance in endurance runners and are modified according to the training performed. The objective of this study was to investigate the ergospirometric and body composition changes in endurance runners during a sports season in relation to their training. Twenty highly trained men endurance runners performed an incremental test until exhaustion (initial, and at 3, 6, and 9 months) on a treadmill to determine maximal oxygen consumption (VO2 max), second ventilatory threshold (VT2), and their associated running speeds. Skinfolds, perimeters, and weights were measured. No changes were obtained in VO2 max or VT2 during the study, although their associated running speeds increased (p < 0.05) after 3 months of the study. Decreases in fat mass (p < 0.05) and muscle mass (p < 0.05) were observed at the end of the season (9 months). Changes occurred in the different skinfolds according to the characteristics of the training performed during the season. In conclusion, vVO2 max and vVT2 increase with a greater volume of kilometres trained and can be adversely affected by loss of muscle mass.


Assuntos
Adaptação Fisiológica , Corrida , Atletas , Humanos , Masculino , Consumo de Oxigênio , Resistência Física , Estações do Ano
3.
Nutr Hosp ; 38(2): 374-382, 2021 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-33371708

RESUMO

INTRODUCTION: Background: it is well known that moderate or vigorous physical exercise produces an increase in free radicals. Aim: the aims of this study were to observe changes in malondialdehyde and antioxidant vitamins after a maximum incremental test, and to relate malondialdehyde and antioxidant vitamin values to performance parameters. Methods: eighty-four male athletes participated in this study. Participants performed a maximum incremental test until exhaustion on a treadmill. Malondialdehyde in plasma and antioxidant vitamins in plasma and erythrocytes were determined before and after the test. Results: in plasma, there was a decrease in malondialdehyde after the test. In erythrocytes, results showed increases in vitamin C and decreases in vitamin E after the test. Maximal oxygen uptake values were associated positively with vitamin C and negatively with malondialdehyde levels before the test. On the other hand, maximal oxygen uptake, total test time, and total test distance were positively related to the malondialdehyde values obtained after the test. Conclusions: a maximum incremental test did not produce any changes in plasma vitamins in athletes. However, it increased the levels of vitamin C in erythrocytes and decreased malondialdehyde values in plasma and vitamin E in erythrocytes. The levels of malondialdehyde, vitamin C and vitamin E were related to performance parameters. These results may be linked to the adaptation of antioxidant systems due to regular training.


INTRODUCCIÓN: Introducción: es sabido que el ejercicio físico moderado o vigoroso produce un aumento de radicales libres. Objetivos: los objetivos del estudio fueron: observar los cambios del malondialdehído y las vitaminas antioxidantes después de un test incremental máximo y relacionar los niveles de malondialdehído y vitaminas antioxidantes con parámetros de rendimiento. Métodos: ochenta y cuatro atletas masculinos participaron en el estudio. Los participantes realizaron un test incremental hasta la extenuación en un tapiz rodante. El malondialdehído en plasma y las vitaminas antioxidantes en plasma y en eritrocitos se determinaron antes y después del test incremental. Resultados: en el plasma hubo una disminución del malondialdehído después de la prueba incremental. En los eritrocitos, los resultados mostraron un aumento de la vitamina C y un descenso de la vitamina E después de la prueba. El consumo máximo de oxígeno se asoció positivamente con la vitamina C e inversamente con el malondialdehído antes del test. Por otro lado, el consumo máximo de oxígeno, el tiempo total del test y la distancia total durante el test se asociaron positivamente con los valores de malondialdehído obtenidos tras el test máximo. Conclusión: un test incremental máximo hasta la extenuación no produjo cambios en las vitaminas antioxidantes del plasma. Sin embargo, sí aumentó los niveles de vitamina C en los eritrocitos y redujo los niveles de malondialdehído en el plasma y los de vitamina E en los eritrocitos. Los niveles de malondialdehído, vitamina C y vitamina E se relacionaron con los parámetros de rendimiento. Estos resultados podrían estar relacionados con la adaptación de los sistemas antioxidantes debido al entrenamiento regular.


Assuntos
Ácido Ascórbico/análise , Atletas , Eritrócitos/química , Tolerância ao Exercício/fisiologia , Malondialdeído/sangue , Vitamina E/análise , Adulto , Ácido Ascórbico/sangue , Desempenho Atlético/fisiologia , Humanos , Masculino , Consumo de Oxigênio , Vitamina A/análise , Vitamina A/sangue , Vitamina E/sangue , Adulto Jovem
4.
Artigo em Inglês | MEDLINE | ID: mdl-32916939

RESUMO

The aim of this study was to determine the possible correlations between essential and toxic trace elements of plasma with several anthropometric and body composition parameters and performance in endurance runners. Sixty-five high-level middle and long-distance runners (21 ± 3 years; 1.77 ± 0.05 m; 64.97 ± 7.36 kg; VO2 max. 67.55 ± 4.11 mL/min/kg) participated in the present study. Abdominal, subscapular, iliac crest, triceps, front thigh and medial calf skinfold thicknesses and an incremental test until exhaustion were recorded. Body, fat, muscle and bone mass were estimated. Plasma trace elements were analyzed with inductively coupled plasma mass spectrometry (ICP-MS). Correlations and simple linear regression were used to assess the relationship between trace elements and several variables. Different skinfolds, fat mass, muscle mass and bone mass correlated positively and negatively with trace elements such as copper, manganese, selenium, vanadium, zinc, lithium, rubidium, strontium, arsenic, beryllium and lead. Lithium was related with performance. In conclusion, endurance training causes changes in the body concentrations of several trace elements that trigger modifications in body composition that may be interesting, if confirmed in the future, for the control of metabolic diseases such as obesity.


Assuntos
Corrida , Selênio , Oligoelementos , Composição Corporal , Humanos , Resistência Física , Corrida/fisiologia , Dobras Cutâneas , Adulto Jovem , Zinco
5.
Artigo em Inglês | MEDLINE | ID: mdl-33348799

RESUMO

Several essential trace minerals play an important role in the endocrine system; however, toxic trace minerals have a disruptive effect. The aim of this research was to determine basal concentrations and the possible correlations between trace minerals in plasma and several plasma hormones in runners. Sixty high-level male endurance runners (21 ± 3 years; 1.77 ± 0.05 m; 64.97 ± 7.36 kg) participated in the present study. Plasma hormones were analyzed using an enzyme-linked immunosorbent assay (ELISA) and plasma trace minerals were analyzed with inductively coupled plasma mass spectrometry (ICP-MS). Correlations and simple linear regression were used to assess the association between trace minerals and hormones. Plasma testosterone concentrations were inversely correlated with manganese (r = -0.543; ß = -0.410; p < 0.01), selenium (r = -0.292; ß = -0.024; p < 0.05), vanadium (r = -0.406; ß = -1.278; p < 0.01), arsenic (r = -0.336; ß = -0.142; p < 0.05), and lead (r = -0.385; ß = -0.418; p < 0.01). Plasma luteinizing hormone (LH) levels were positively correlated with arsenic (r = 0.298; ß = 0.327; p < 0.05) and cesium (r = 0.305; ß = 2.272; p < 0.05), and negatively correlated with vanadium (r = -0.303; ß = -2.467; p < 0.05). Moreover, cortisol concentrations showed significant positive correlations with cadmium (r = 0.291; ß = 209.01; p < 0.05). Finally, insulin concentrations were inversely related to vanadium (r = -0.359; ß = -3.982; p < 0.05). In conclusion, endurance runners living in areas with high environmental levels of toxic minerals should check their concentrations of anabolic hormones.


Assuntos
Hormônios , Minerais , Oligoelementos , Arsênio/sangue , Cádmio/sangue , Ensaio de Imunoadsorção Enzimática , Hormônios/sangue , Humanos , Masculino , Manganês/sangue , Espectrometria de Massas , Minerais/sangue , Selênio/sangue , Oligoelementos/sangue
6.
Artigo em Inglês | MEDLINE | ID: mdl-32806586

RESUMO

The aim of this study was to determine the possible changes in plasma of several hormones such as Luteinizing Hormone, Testosterone, Cortisol and Insulin in endurance runners during the sports season. Twenty-one high-level male endurance runners (22 ± 3.2 years, 1.77 ± 0.05 m) participated in the study. Basal plasma hormones were measured at four moments during the season (initial, 3, 6 and 9 months), and were analyzed using ELISA (enzyme-linked immunosorbent assay). Testosterone and Luteinizing Hormone (LH) suffered very significant decreases (p < 0.01) at 3 months compared with the beginning and an increase (p < 0.05) at 6 and 9 months compared with 3 months. Insulin level was significantly lower (p < 0.05) at 3, 6 and 9 months compared with the initial test. Insulin and cortisol were associated inversely (r = 0.363; ß = -0.577; p = 0.017) and positively (r = 0.202; ß = 0.310; p = 0.043), respectively, with the amount of km per week performed by the runners. There was a significant association between km covered at a higher intensity than the anaerobic threshold and I (r = 0.580; ß = -0.442; p = 0.000). Our findings indicate that testosterone, LH and insulin were more sensitive to changes in training volume and intensity than cortisol in high-level endurance runners. Basal testosterone and LH concentrations decrease in athletes who perform a high volume of aerobic km in situations of low energy availability.


Assuntos
Atletas , Resistência Física , Adulto , Humanos , Hidrocortisona/metabolismo , Hormônio Luteinizante/metabolismo , Masculino , Estações do Ano , Testosterona/metabolismo , Adulto Jovem
7.
Biol Trace Elem Res ; 189(2): 387-394, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30194520

RESUMO

The current information about the effect of physical exercise on the body concentrations of several minerals is still limited, both in the acute (short-term) and adaptive (long-term) responses. So, this manuscript aims, on the one hand, to assess the possible differences on basal levels of cobalt (Co), copper (Cu), and manganese (Mn) concentrations in serum and urine between athletes and sedentary participants and, on the other hand, to evaluate the effect of an acute progressive physical exercise until voluntary exhaustion on the serum and urinary concentrations of Co, Cu, and Mn. Two groups participated in this survey, one was formed by untrained, sedentary males (CG; n = 26), and the other group was constituted by national endurance (long and middle distances) athletes (AG; n = 21). All participants were from the same region of Spain. Participants of both groups performed a physical test on a treadmill, reaching voluntary exhaustion. Blood and urine samples of each participant were collected before and at after the tests. Once obtained and processed, the concentrations of Co, Cu, and Mn elements were analyzed by inductively coupled plasma mass spectrometry (ICP-MS). The differences in the studied variables were evaluated using a mixed model by means of an ANOVA and Bonferroni post hoc tests. In the comparison of the pre-test values between groups, the results showed that serum concentrations of Mn were significantly lower in CG than in AG (p < 0.01). In urine, Co and Mn levels were significantly higher among CG participants (p < 0.01) than among AG ones, while in the case of Cu, the values were lower (p < 0.01) in the CG than in the AG. Regarding the effects of the effort tests, no significant changes were found among the participants of the CG. It was observed that the serum concentrations of Co (p < 0.05) and Cu (p < 0.01) decreased after the test among the AG participants. Also, the results showed that there were no statistical differences in Co and Mn values (expressed in µg/g creatinine). However, the urinary post-test Cu concentrations were lower (p < 0.05) among AG participants. In basal conditions, serum concentrations of Mn were significantly lower in CG than in AG. In urine, Co and Mn levels were significantly higher among CG participants and Cu level was significantly lower in CG, a fact which may reflect adaptive responses to exercise. An incremental exercise to exhaustion in AG produces a decrease in Co and Cu serum concentrations, as well as in urinary excretion of Cu.


Assuntos
Cobalto/sangue , Cobalto/urina , Cobre/sangue , Cobre/urina , Exercício Físico/fisiologia , Manganês/sangue , Manganês/urina , Adulto , Antropometria , Atletas/estatística & dados numéricos , Hematócrito , Hemoglobinas/metabolismo , Humanos , Masculino , Adulto Jovem
8.
J Sports Med Phys Fitness ; 58(12): 1713-1719, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29072036

RESUMO

BACKGROUND: The main objective of this study was to observe any changes and possible adaptations produced in MDA and antioxidants vitamins on plasma and erythrocytes in endurance male athletes among an athletic season (12 months). METHODS: Twenty three long and middle distance male athletes participated in this study. Basal MDA on plasma and antioxidant vitamins in plasma and erythrocytes were measured at four moments along the season (0, 3, 6 and 9 months). Fatty acid concentrations in erythrocytes were obtained to determine lipid peroxidation indexes. RESULTS: In plasma, vitamin C suffered significant decreases at 3 and 6 months compared with the begin (P<0.01), and an increase at 9 months, compared with 3 months. On the other hand, vitamin A level was significantly lower at 9 months compared with the other periods (P<0.01 compared with 0 and 6 months; P<0.05 compared with 3 months). In erythrocytes, significant decreases were observed in vitamin E among the season at 6 months and an increase from 6 to 9 months (P<0.05). Vitamin A suffers a significant decrease in both for competitive periods, at 3 and 9 months, compared with the beginning of the season. The most of changes in lipid peroxidation indexes were produced along the firsts 3 months. CONCLUSIONS: 1) Physical training improves the antioxidant systems in order to reduce lipid peroxidation in trained athletes along the season; 2) PUFA/SFA ratios seem more reliable than MDA to observe oxidative stress.


Assuntos
Antioxidantes/análise , Peroxidação de Lipídeos , Estresse Oxidativo , Fenômenos Fisiológicos da Nutrição Esportiva , Vitaminas/sangue , Ácido Ascórbico/sangue , Atletas , Eritrócitos/química , Exercício Físico , Humanos , Masculino , Resistência Física , Esportes , Vitamina A/sangue , Vitamina E/sangue
9.
Biol Trace Elem Res ; 186(2): 361-369, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29623649

RESUMO

The aim of the present study was to determine changes occurring in serum and urine concentrations of essential trace elements with proven essentiality (molybdenum, selenium, and zinc) as a result of performing an acute physical activity until exhaustion in middle- and long-distance runners who live in the same area of Extremadura (Spain). Twenty-one Spanish national middle- and long-distance runners and 26 sedentary students of a similar age were recruited for the study. Both groups ran on a treadmill until exhaustion, starting at a speed of 10 and 8 km/h, respectively, and increasing the speed at 1 km/h every 400 m, without modifying the slope, always within the recommended parameters. Serum and urine samples were obtained from all subjects before and after the tests. Analysis of trace metals was performed by inductively coupled plasma mass spectrometry (ICP-MS). Resting serum and urinary concentrations between groups were compared using the Student t test, and the Wilcoxon test was used to analyze the trends of changes before and after the effort. The results showed that molybdenum concentrations were significantly higher in athletes than in controls (p < 0.01). Selenium (p < 0.05) and zinc (p < 0.01) concentrations were significantly lower in athletes than in controls. When we compared the serum concentrations before and after the test in the controls, only in the case of selenium (p = 0.006), a significant increase was observed after the test. However, this signification disappears with the corrections for hematocrit. Athletes' serum concentrations of Se (p = 0.004) and Zn (p = 0.005) lowered at the end of the test. Also, the results showed that there were no statistical urinary concentration (expressed in µg/g creatinine) changes in Mo and Se. Zn urinary concentration increased at the end of exercise (p = 0.018), since an incremental exercise to exhaustion in middle- and long-distance elite athletes produces a decrease in Se and Zn serum concentrations but Zn urinary concentration increased. In conclusion, athletes show higher serum concentrations of molybdenum and lower serum concentrations of selenium and zinc than sedentary subjects. Additionally, a treadmill test until exhaustion provokes a decrease in serum concentration of selenium and zinc and a higher excretion of urinary zinc. Serum concentrations of Se and Zn should be carried out in order to avoid any possible deficit cases and to establish the optimal supplementation.


Assuntos
Atletas , Exercício Físico/fisiologia , Fadiga Muscular/fisiologia , Oligoelementos/sangue , Oligoelementos/urina , Adolescente , Adulto , Hematócrito , Hemoglobinas/metabolismo , Humanos , Masculino , Molibdênio/sangue , Molibdênio/urina , Corrida/fisiologia , Selênio/sangue , Selênio/urina , Adulto Jovem , Zinco/sangue , Zinco/urina
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