Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 9 de 9
Filtrar
Mais filtros








Base de dados
Intervalo de ano de publicação
1.
J Hum Kinet ; 78: 121-129, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34025870

RESUMO

This study aimed to assess the effect of a maximum incremental stress test through urinary concentrations of steroid hormones in trained cyclists. Twenty male cyclists participated in the study (23.83 ± 2.3 years; 1.76 ± 0.03 m; 66.94 ± 3.59 kg; training volume: 20.50 ± 2.35 h/week). Athletes performed a maximum incremental test until exhaustion on a cycle ergometer and urine samples were collected at three different time points: before, immediately after, and 48 h after the test. Lactate, creatinine and urinary concentrations of testicular and adrenal androgens were obtained as well as urinary concentrations of glucocorticoid hormones. An increase in lactate was observed after the test (p < 0.01). There were decreases in the urinary excretion of androgenic hormones after the test, which were significant in testosterone, androsterone, androstenedione, total adrenal androgen and total testicular androgen (p < 0.05). The values were restored after 48 h (p < 0.05). Urinary cortisol concentrations decreased after the test (p < 0.05). A decrease was also observed in the ratio of anabolic/catabolic hormones (p < 0.05) increasing 48 h after the test (p < 0.05). Increased acute physical exercise until exhaustion causes variations in the urinary excretions of steroid hormones which were restored 48 h after exercise. Urinary excretion of steroid hormones could be a valid method of monitoring training loads.

2.
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
3.
Biol Trace Elem Res ; 195(1): 39-45, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31359333

RESUMO

The aim of the present study was to determine changes occurring in the erythrocyte concentrations of arsenic (As), cadmium (Cd) and lead (Pb) in highly trained males, moderately trained males and sedentary men living in the same area of Extremadura (Spain). Thirty sedentary subjects (24.34 ± 3.02 years) with no sports practice and a less active lifestyle formed the control group (CG). Twenty-four moderately trained subjects (23.53 ± 1.85 years), who practised sports at a moderate level between 4 and 7 h/week, without any performance objective and without following any type of systematic training, formed the group of subjects with a moderate degree of training (MTG). And 22 professional cyclists (23.29 ± 2.73 years) at the beginning of their sports season, who trained for more than 20 h/week formed the high-level training group (HTG). Erythrocyte samples from all subjects in a fasting stage were collected, washed and frozen at -80 °C until analysis. Erythrocyte analysis of the trace elements As, Cd and Pb was performed by inductively coupled plasma mass spectrometry (ICP-MS). As concentration was lower in CG (p < 0.01) and MTG (p < 0.01) than HTG. Cd (p < 0.001) and Pb (p < 0.05) concentrations were higher in CG than HTG. All results were expressed in µg/g Hb. Physical training produces a decrease in erythrocyte concentrations of Cd and Pb, as an adaptation in order to avoid their accumulation in the cells and preserve correct cellular functioning. The higher As concentration should be investigated in high-level sportsmen because of a possible negative effect on the cells.


Assuntos
Arsênio/sangue , Cádmio/sangue , Eritrócitos/química , Exercício Físico , Chumbo/sangue , Adulto , Teste de Esforço , Humanos , Espanha , Adulto Jovem
4.
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
5.
J Int Soc Sports Nutr ; 15(1): 28, 2018 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-29898738

RESUMO

BACKGROUND: The aim of the present study was to determine changes in the serum concentrations of trace elements Cobalt (Co), Molybdenum (Mo) and Zinc (Zn) among high-level sportsmen. METHODS: Eighty professional athletes of different metabolic modalities (aerobic, anaerobic and aerobic-anaerobic), were recruited before the beginning of their training seasons. Thirty-one sedentary participants of the same geographic area constituted the control group. Co, Mo and Zn analysis was performed by Inductively Coupled Plasma Mass Spectrometry (ICP-MS). RESULTS: Serum concentration of Mo (p < 0.001) was higher among sportsmen compared to the control group values. Separated by modalities, the concentrations of Co in the aerobic-anaerobic athletes were lower (p < 0.01) than in the control group as well as than in the other athletes. The highest Mo concentration was found in anaerobic sportsmen (p < 0.001), followed by aerobic-anaerobic (p < 0.001) being both statistically higher in comparison with the control group. In relation to Zn, it was observed that aerobic-anaerobic (p < 0.001) and anaerobic (p < 0.001) sportsmen showed higher concentrations than the control participants. However, aerobic sportsmen showed lower concentrations (p < 0.01) than controls. CONCLUSION: This data manifest that long-term, daily physical training may induce variations in serum concentrations of several essential elements among sportsmen in comparison to untrained men and that these changes seems to be related to the sports modality practiced.


Assuntos
Cobalto/sangue , Molibdênio/sangue , Fenômenos Fisiológicos da Nutrição Esportiva , Esportes/classificação , Zinco/sangue , Adolescente , Atletas , Estudos de Casos e Controles , Humanos , Masculino , Comportamento Sedentário , Oligoelementos/sangue , Adulto Jovem
6.
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
7.
Artigo em Inglês | MEDLINE | ID: mdl-29449792

RESUMO

BACKGROUND: The aim of the present study was to determine changes in serum concentrations of trace elements Cooper (Cu), Chromiun (Cr), Manganesum (Mn), Nickel (Ni) and Selenium (Se) in high-level sportsmen. METHODS: Eighty professional athletes of different metabolic modalities, were recruited before the start of their training period. Thirty one sedentary participants of the same geographic area constituted the control group. Cu, Cr, Mn, Ni and Se analysis was performed by Inductively Coupled Plasma Mass Spectrometry (ICP-MS). RESULTS: Higher concentrations of Cr (p < 0.001), Mn (p < 0.085), and Ni (p < 0.001) were found in sportsmen in comparison to controls, inversely, Se values were lower (p < 0.001) among sportsmen. When sportsmen were classified by metabolic modalities, it was found that aerobic-anaerobic group had higher (p < 0.01) Cu concentrations than controls and the other sportsmen. The highest Cr values were found in aerobic participants. For Mn, the major levels were found in aerobic and aerobic-anaerobic groups as well (p < 0.001). The lowest Se levels were found among anaerobic sportsmen (p < 0.001). CONCLUSION: This research showed that daily, continuum physical training induced alterations in serum essential minerals concentrations, as well as that these changes can be dependent of the exercise modality practiced.


Assuntos
Cromo/sangue , Cobre/sangue , Compostos de Manganês/sangue , Níquel/sangue , Selênio/sangue , Fenômenos Fisiológicos da Nutrição Esportiva , Adolescente , Adulto , Antropometria , Atletas , Dieta , Exercício Físico , Humanos , Masculino , Espectrometria de Massas , Comportamento Sedentário , Esportes/classificação , Adulto Jovem
8.
J Trace Elem Med Biol ; 45: 136-141, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29173470

RESUMO

BACKGROUND: Many substances poured out from industries can be toxic to humans and can impair physical performance. Besides, physical training may modify the body concentrations of these substances as a result of physiological adaptations. OBJECTIVES: The aim of the study was to determine if different modalities of exercise might affect serum concentrations of toxic trace elements in sportsmen. METHODS: 80 Spanish national sportsmen were recruited before the start of their training period. All the athletes had been training regularly for the previous two years with a rigorous training target at high-level competition. 31 sedentary participants from the same geographic area formed the control group. Serum arsenic, beryllium, cadmium, cesium and lead samples were analyzed with an ICP-MS. RESULTS: Serum concentrations were higher among the sportsmen group than among the control group, being highly significant in cases of Be from 0.043±0.019 to 0.074±0.029µg/L, Cs from 0.693±0.305 to 1.358±0.569µg/L and Pb from 0.162±0.171 to 2.375±1.699µg/L; and significant in the case of Cd from 0.046±0.027 to 0.067±0.059µg/L. However, if they were separated according to different sport modalities, it was found that, although they had higher concentrations than controls, there were elements that changed their concentrations in relation to the metabolic type of activity performed. CONCLUSIONS: In some cases physical exercise induces favorable adaptations to avoid environmental pollution damage. Endurance training (65-75% VO2max) can be considered the most effective exercise to prevent toxicity effects. However, integral-matrixes analysis are required in further research to overcome some controversial behaviors of some elements.


Assuntos
Metabolismo Energético/fisiologia , Exercício Físico/fisiologia , Adaptação Fisiológica , Arsênio/sangue , Berílio/sangue , Cádmio/sangue , Césio/sangue , Humanos , Chumbo/sangue , Resistência Física/fisiologia
9.
Eur J Appl Physiol ; 113(6): 1469-75, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23266510

RESUMO

Some studies suggest that performing strength training may cause alterations on the hypothalamic pituitary axis, resulting in steroid hormone variations. Intense training has been associated to slow the concentrations of estrogens and progesterone in women. The main purpose of this study was to evaluate the effects of strength training on the urinary steroid concentrations across the menstrual cycle phases. Twenty healthy women, regularly menstruating and not using pharmacologic contraceptives, performed a strength training during 8 weeks. Participants worked out 3 sets × 10 repetitions, with 2 min recovery time between sets, at 70-75 % of one maximum strength repetition. Urine samples were taken in three different phases of the menstrual cycle (menstrual, follicular and luteal) and they were collected both before and after training. Testosterone, DHEA, cortisol, cortisone, estradiol and progesterone concentrations were determined by gas chromatography-mass spectrometry. The results showed a significant decline after training in the urinary excretion of estradiol, during the menstrual and follicular phase, and progesterone, during the menstrual and luteal phase. No significant difference was observed for other steroid hormones. These data demonstrated that strength training can play an important role in the estrogen and progesterone metabolism in women, decreasing their levels across the menstrual cycle.


Assuntos
Exercício Físico , Hormônios Esteroides Gonadais/urina , Ciclo Menstrual/urina , Feminino , Humanos , Adulto Jovem
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA