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1.
Reprod Biol Endocrinol ; 16(1): 114, 2018 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-30415644

RESUMO

It is universally accepted that lifestyle interventions are the first step towards a good overall, reproductive and sexual health. Cessation of unhealthy habits, such as tobacco, alcohol and drug use, poor nutrition and sedentary behavior, is suggested in order to preserve/improve fertility in humans. However, the possible risks of physical exercise per se or sports on male fertility are less known. Being "fit" does not only improve the sense of well-being, but also has beneficial effects on general health: in fact physical exercise is by all means a low-cost, high-efficacy method for preventing or treating several conditions, ranging from purely physical (diabetes and obesity) to psychological (depression and anxiety), highly influencing male reproduction. If male sexual and reproductive health could be positively affected by a proper physical activity, inadequate bouts of strength - both excessive intensity and duration of exercise training - are more likely to have detrimental effects. In addition, the illicit use of prohibited drugs (i.e. doping) has reached pandemic proportions, and their actions, unfortunately very often underestimated by both amateur and professional athletes, are known to disrupt at different levels and throughout various mechanisms the male hypothalamic-pituitary-gonadal axis, resulting in hypogonadism and infertility.


Assuntos
Dopagem Esportivo , Fertilidade/fisiologia , Sistema Hipotálamo-Hipofisário/fisiologia , Esportes/fisiologia , Diabetes Mellitus/fisiopatologia , Diabetes Mellitus/prevenção & controle , Humanos , Hipogonadismo/fisiopatologia , Infertilidade Masculina/fisiopatologia , Masculino , Obesidade/fisiopatologia , Obesidade/prevenção & controle
2.
Clin J Sport Med ; 24(4): 302-7, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24389625

RESUMO

OBJECTIVE: To examine the effects of 16 weeks of intensive cycling training on seminal reactive oxygen species (ROS), malondialdehyde (MDA), superoxide dismutase (SOD), catalase, and total antioxidant capacity (TAC) in male road cyclists. DESIGN: Repeated measures design. SETTING: The Exercise Physiology Laboratory of the Urmia University. PARTICIPANTS: Twenty-four healthy nonprofessional male road cyclists (aged 17-26 years) participated in this study. INTERVENTIONS: All subjects participated in 16 weeks of intensive cycling training. The semen samples were collected, respectively, at baseline (T1), immediately (T2), 12 (T3), and 24 (T4) hours after the last training session in week 8; immediately (T5), 12 (T6), and 24 (T7) hours after the last training session in week 16; and 7 (T8) and 30 (T9) days after the last training session in week 16. MAIN OUTCOME MEASURES: Total antioxidant capacity and SOD were measured by colorimetric assay. The levels of ROS were measured by a chemiluminescence assay. Malondialdehyde levels were measured by thiobarbituric acid reactive substance assay. Catalase was measured by monitoring the initial rate of disappearance of hydrogen peroxide (initial concentration 10 mM) at 240 nm. RESULTS: The levels of seminal ROS and MDA increased (P < 0.008) and remained high after 30 days of recovery. The levels of seminal SOD, catalase, and TAC decreased (P < 0.008) and remained low after 30 days of recovery (P < 0.008). CONCLUSIONS: Sixteen weeks of intensive cycling training may have deleterious consequences for spermatozoa and hence may affect sperm healthy parameters in male cyclists.


Assuntos
Antioxidantes/metabolismo , Ciclismo/fisiologia , Malondialdeído/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Sêmen/enzimologia , Adolescente , Adulto , Catalase/metabolismo , Dieta , Humanos , Infertilidade Masculina/etiologia , Masculino , Estresse Oxidativo , Análise do Sêmen , Superóxido Dismutase/metabolismo , Adulto Jovem
3.
Eur J Appl Physiol ; 112(9): 3267-73, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22234399

RESUMO

Physical exercise promotes many health benefits. The present study was undertaken to assess possible semen and hormone differences among physically active (PA) subjects and sedentary subjects (SE). The analyzed qualitative sperm parameters were: volume, sperm count, motility, and morphology; where needed, additional testing was performed. The measured hormones were: follicle-stimulating hormone (FSH), luteinizing hormone (LH), testosterone (T), cortisol (C), and the ratio between T and C (T/C). Maximum oxygen consumption was also assessed to check for differences in fitness level. Statistically significant differences were found for several semen parameters such as total progressive motility (PA: 60.94 ± 5.03; SE: 56.07 ± 4.55) and morphology (PA: 15.54 ± 1.38, SE: 14.40 ± 1.15). The seminological values observed were supported by differences in hormones, with FSH, LH, and T being higher in PA than in SE (5.68 ± 2.51 vs. 3.14 ± 1.84; 5.95 ± 1.11 vs. 5.08 ± 0.98; 7.68 ± 0.77 vs. 6.49 ± 0.80, respectively). Likewise, the T/C ratio, index of anabolic versus catabolic status, was also higher in PA (0.46 ± 0.11 vs. 0.32 ± 0.07), which further supports the possibility of an improved hormonal environment. The present study shows that there are differences in semen and hormone values of physically active subjects and sedentary subjects. Physically active subjects seem to have a more anabolic hormonal environment and a healthier semen production.


Assuntos
Hormônios/sangue , Atividade Motora/fisiologia , Comportamento Sedentário , Análise do Sêmen , Adolescente , Adulto , Estudos de Casos e Controles , Exercício Físico/fisiologia , Hormônio Foliculoestimulante/sangue , Hormônios/análise , Humanos , Hormônio Luteinizante/sangue , Masculino , Sêmen/citologia , Sêmen/fisiologia , Contagem de Espermatozoides , Adulto Jovem
4.
Eur J Sport Sci ; 22(9): 1335-1342, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34256680

RESUMO

Endurance exercise induces notable acute hormonal responses on the gonadal and adrenal hormones. The purpose of this study was to assess the changes in salivary testosterone (Ts), salivary cortisol (Cs) and T/C ratio during long-distance triathlon. Ten well-trained male triathletes participated in the study and were assessed for hormonal changes at four time-points (pre-competition, post-swimming, post-cycling, and post-running phases). Ts decreased from pre-competition to post-swimming (from 93.37 pg/mL to 57.63 pg/mL; p < .01) and increased during two other parts of the competition to almost pre-competition values (cycling: 79.20 pg/mL, p = .02; running: 89,66 pg/mL, p = .04, respectively). Cs showed a similar behaviour; decreasing in the post-swimming phase (1.74 pg/mL) and increasing in the other transitions (post-cycling: 7.30 pg/mL; post-running: 13.31 pg/mL), with significant differences between pre-competition and post- competition values (p = .01). Conversely, T/C increased significantly from pre-competition to post-swimming phase (p = .04) to later decrease until the end of the competition. Overall, T/C significantly decreased (p < .05). In conclusion, during an Ironman triathlon, hormone values fluctuate in response to the demands of the competition. Ts and Cs decrease after-swimming, increase after-cycling and reach the maximum values after-running. T/C reflects overall catabolic status.


Assuntos
Hidrocortisona , Corrida , Ciclismo/fisiologia , Humanos , Masculino , Resistência Física/fisiologia , Corrida/fisiologia , Natação/fisiologia , Testosterona
5.
J Strength Cond Res ; 24(12): 3334-42, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21068682

RESUMO

The addition of fructose (F) to a glucose (G) supplement may modify the metabolic response during exercise; however, its effect on perceived exertion (PE) and its influence on postprandial metabolism have not been jointly studied in different types of exercise. This study sought to assess the acute effects of F addition to a G supplement on PE and on the postprandial metabolic response during a single bout of either strength exercise (SE) or endurance exercise (EE). Twenty physically trained men ingested an oral dose of G or GF 15 minutes before starting a 30-minute session of SE (10 sets of 10 repetitions of half squat) or EE (cycling). The combination resulted in 4 randomized interventions in a crossover design in which all subjects performed all experimental conditions: G + SE, GF + SE, G + EE, and GF + SE. Perceived exertion, heart rate (HR), G, insulin, lactate, and urinary catecholamine levels were measured before exercise, during the exercise, and during acute recovery. Perceived exertion during exercise was lower for GF than for G during SE and EE (mean ± SD; 8.95 ± 0.62 vs. 9.26 ± 0.65, p < 0.05 and 7.47 ± 0.84 vs. 7.74 ± 0.93, p < 0.05, respectively). The glycemic peak in GF + SE was lower than in G + SE (p < 0.05), and there was a second peak during recovery (p < 0.05), whereas in EE, no difference in blood G levels was noted between G and GF supplements. Moreover, HR, urinary adrenalin, and noradrenalin were lower in GF than in G (p < 0.05), though only for EE. The results showed that PE is positively affected by GF supplementation for both SE and EE and thus may be a useful dietary strategy for helping to achieve higher training loads.


Assuntos
Suplementos Nutricionais , Frutose/farmacologia , Glucose/farmacologia , Força Muscular/efeitos dos fármacos , Resistência Física/efeitos dos fármacos , Esforço Físico/efeitos dos fármacos , Administração Oral , Adulto , Biomarcadores/análise , Glicemia/análise , Catecolaminas/urina , Estudos Cross-Over , Epinefrina/urina , Frutose/administração & dosagem , Glucose/administração & dosagem , Frequência Cardíaca/fisiologia , Humanos , Insulina/sangue , Lactatos/sangue , Masculino , Norepinefrina/urina , Consumo de Oxigênio/fisiologia
6.
J Strength Cond Res ; 23(7): 2073-82, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19855333

RESUMO

This experiment was designed to assess the acute (Study I) and cumulative response (Study II) of muscle performance to differing recovery times after exposure to whole body vibration (WBV). All subjects (mean age 19.7 +/- 1.9) were healthy and physically active. In both studies, subjects were exposed to a WBV bout of 6 exposures of 60 seconds each, with frequency of 30 Hz and amplitude of 4 mm. In Study I, subjects (n = 30) underwent 3 trials (1 per day) on different days with a 2-day wash-out period between trials; each trial included either a 1, 2, or 3 minutes of recovery between exposures to WBV. All subjects underwent all trials, which were randomly assigned. Jump ability and muscle power were measured before and after each bout. In Study II, subjects (n = 45) underwent 12 sessions of WBV training in 4 weeks (3 bouts/wk). The subjects were randomly assigned to 1 of the following 3 groups: WBV with 1-minute recovery periods between exposures, WBV with 2-minute recovery periods between exposures, or control group. Jump ability, muscle power, and strength were measured before and after each bout. In the acute study (I), recovery times of 1 and 2 minutes enhanced all measured parameters (p < 0.05), with the 2-minute recovery being more effective. In the long-term study (II), however, although both periods also enhanced the measured parameters (p < 0.05), the 1-minute recovery proved more effective because the response was modified by systematic stimulation. In conclusion, 2-minute recovery periods provided the most effective acute enhancement of muscle activation, whereas the 1-minute recovery provided a more effective cumulative enhancement of muscle power and jump ability.


Assuntos
Desempenho Atlético , Força Muscular/fisiologia , Músculo Esquelético/fisiologia , Vibração , Adulto , Humanos , Masculino , Adulto Jovem
7.
J Androl ; 23(2): 194-201, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-11868812

RESUMO

The objective of this study was to assess the temporal effects of sperm incubation at body temperature with various amounts of human serum albumin (HSA) on motion parameters and phosphatidylserine externalization, an expression of membrane integrity. Purified sperm populations were prepared by discontinuous gradient separation, incubated at 37 degrees C in 3 different culture conditions (human tubal fluid [HTF] alone, HTF plus 0.3% HSA, and HTF plus 3% HSA) and evaluated at 0, 1, 3, 6, and 24 hours. Annexin V binding was used to monitor membrane translocation of phosphatidylserine and a computer-assisted semen analyzer was used to evaluate motion parameters. All incubation conditions led to a time-dependent, significant decline in sperm motion parameters and an increase in exposure of phosphatidylserine (annexin V+, live cells) to the outer leaflet of the plasma membrane in both patients and donors. Patients had a higher degree of motility loss and externalization of phosphatidylserine than donors. The decline in the percentage of normal cells (annexin V-, live) was greater in HTF alone up to 6 hours, and the decline in the percentages of motile and rapid sperm were greater in HTF alone throughout 24 hours when compared with HSA supplementation. We conclude that prolonged incubation of purified populations of highly motile human spermatozoa at body temperature was associated with significant motility loss and membrane changes as revealed by phosphatidylserine translocation. A higher concentration of HSA resulted in a relative protective effect against such impairments, particularly during the first 6 hours of incubation. Under the experimental conditions tested, significant differences were observed between infertile men and fertile controls.


Assuntos
Fosfatidilserinas/metabolismo , Motilidade dos Espermatozoides/fisiologia , Espermatozoides/metabolismo , Anexina A5/metabolismo , Transporte Biológico , Temperatura Corporal , Membrana Celular/fisiologia , Diagnóstico por Computador , Humanos , Infertilidade Masculina/diagnóstico , Infertilidade Masculina/fisiopatologia , Masculino , Valores de Referência , Fatores de Tempo , Doadores de Tecidos
8.
J Electromyogr Kinesiol ; 22(4): 612-9, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22341590

RESUMO

The purpose of the present study was to assess the ability of TMG in detecting mechanical fatigue induced by two different resistance exercises on biceps brachii: high-volume (HV), and high-load (HL). Sixteen healthy subjects (age 25.1±2.6years; body mass 79.9±8.9kg; height 179±7.4cm) performed arm-curl in two different protocols (HV: 8×15×10kg, HL: 5×3×30kg). Tensiomyography was used to assess muscle response to both exercise protocols. The contractile capacity of biceps brachii significantly varied by means of the effects of potentiation and fatigue mechanisms that take place at different exercise phases. The most significant changes correspond to values of maximum radial displacement of muscle belly (D(m)), sustained contraction time (T(s)), relaxation time (T(r)), and contraction velocity (V(c)). The behavior of these parameters is, in general, similar in both exercise protocols, but they show subtle differences among them. During the first set, in both protocols, values for V(c) increase, along with a decrease in T(r), T(s), and D(m) values. Fatigue onset was evident from changes in such parameters, with HL being the first in showing these mechanisms. Tensiomyography has been shown to be highly sensitive in detecting fatigue-induced changes.


Assuntos
Exercício Físico/fisiologia , Contração Muscular/fisiologia , Fadiga Muscular/fisiologia , Músculo Esquelético/fisiologia , Miografia/métodos , Resistência Física/fisiologia , Treinamento Resistido/métodos , Adulto , Humanos , Masculino , Esforço Físico/fisiologia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
9.
Fertil Steril ; 92(6): 1941-6, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19013565

RESUMO

OBJECTIVE: To investigate the effect of different training modalities on various markers of semen quality. DESIGN: Crossover study. SETTING: Medical school. PATIENT(S): Forty-five men participated voluntarily in the study, being allocated into three groups according to their sports practice. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Sperm parameters (volume, liquefaction time, pH, viscosity, sperm count, motility, and morphology). RESULT(S): Sperm concentration; total sperm number; type "a," "b," and "d" velocity; and morphology were significantly different among the practitioners of the three different training modalities. Morphology was the parameter showing the greatest difference, even reaching clinical relevance for the triathlete group (4.7%, poor prognosis pattern). In addition, these parameters tended to decrease as training requirements increased. CONCLUSION(S): There are differences in the seminal profiles of individuals exercising in different modalities. The differences are more marked as intensity and volume of exercise increase, especially for morphology. These variables ought to be carefully analyzed and taken into account when designing a training protocol, especially with higher-level athletes, so that reproductive function is not compromised.


Assuntos
Exercício Físico/fisiologia , Infertilidade Masculina/fisiopatologia , Medicina Reprodutiva , Sêmen/fisiologia , Esportes/fisiologia , Adolescente , Adulto , Humanos , Masculino , Atividade Motora , Prognóstico , Adulto Jovem
10.
J Strength Cond Res ; 21(2): 470-5, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17530948

RESUMO

The aim of the present study was to analyze the effect of whole-body vibration on energy expenditure, as well as on exercise intensity, during and immediately after a typical set of exercises for muscle hypertrophy in physically active subjects. Seventeen male university students (mean age 18.3 +/- 0.24 years) volunteered to perform 2 different training exercises: half squat (HS), and half squat with vibration (HSV). Both exercises were performed by all subjects on the vibration platform (with vibration only for HSV), the sequence order being assigned randomly. Energy expenditure (EE), respiratory exchange ratio, perceived exertion (PE), and heart rate were recorded for baseline, exercise, and short-recovery conditions. Training consisted of 5 sets of 10 repetitions of HS and HSV, with a 2-minute recovery interval between sets. Analysis of variance with repeated measurements and Bonferroni correction, as well as effect size were used for statistical calculations. Results indicated that EE and PE were significantly higher in the HSV group, during both exercise and recovery. Heart rate did not differ significantly between groups. Thus, it would appear that HS strength training could be rendered more energy-efficient through the addition of vibration. Moreover, it would be feasible to introduce vibration exercises into regular training programs, particularly those whose key objective is muscle hypertrophy along with fat reduction.


Assuntos
Metabolismo Energético , Músculo Esquelético/fisiologia , Educação Física e Treinamento/métodos , Vibração , Adolescente , Adulto , Análise de Variância , Frequência Cardíaca/fisiologia , Humanos , Masculino , Esforço Físico/fisiologia , Reprodutibilidade dos Testes
11.
Rev. méd. Urug ; 26(3): 178-186, set. 2010. tab
Artigo em Espanhol | LILACS | ID: lil-563814

RESUMO

Introducción: la vitrificación es una técnica de criopreservación de las denominadas "rápidas". En comparación con los tradicionales procesos de congelación lenta, la estrategia de vitrificación permite la eliminación total de la formación de cristales tanto intracelular como extracelularmente. Permite poner las células directamente en el crioprotector y sumergirlas en N2 líquido. Su aplicación en el mundo ha ido creciendo exponencialmente y se puede aplicar tanto a ovocitos como a embriones en cualquier estadio. Objetivos: revisión de la técnica de vitrificación y presentación de la experiencia de dos años en el Centro Iberoamericano de Reproducción Asistida, la primera en Uruguay. Material y método: se incluyeron 17 pacientes de las que se han vitrificado y desvitrificado embriones. Se usó el método comercial Cryotop con las soluciones de vitrificación de Kitazato. Resultados: con una media de embriones vitrificados de 2,71 (±0,69) por paciente, la tasa de supervivencia global de los embriones tras la desvitrificación fue de 93,4%. Con una media deembriones transferidos de 2,41 ±0,62), la tasa final de embarazo fue de 47,1%. La edad de las pacientes en las que se logra embarazo es menor (media 30,0 ±2,51) que las que no lo logran.Conclusiones: la vitrificación como método de criopreservación se muestra prometedor y como buen sustituto de las técnicas de congelación lentas, debido a su alta tasa de éxito, su fiabilidad y la rapidez de ejecución, con resultados reproducibles.


Introduction: vitrification is a cryopreservation technique that forms part of the so called "fast" cryopreservation techniques. Compared to traditional slow freezing processes, vitrification enables the total elimination of both intracellular and extracellular crystal formation. It allows for placing the cells directly on the cryoprotector and submersing them in liquid nitrogen. Its application around the world has exponentially grown and the technique may be applied both to ovocytes and embryos at all stages. Objectives: to carry out a review of the vitrification technique, the first one to be conducted in Uruguay, and to present the two-year experience at the Ibero-American Center for Assisted Reproduction. Method: we included 17 patients in our study, the embryos of which have been vitrified and unvitrified. We used the commercial Cryotop method with the Kitazato vitrification solutions. Results: with an average of 2,71 (±0,69) vitrified embryos per patients, global embryo survival rate after vitrification was 93,4%. With an average of 2,41 (±0,62) embryos transferred , the final pregnancy rate was 47,1%. The average age of patients who succeeded in getting pregnant is lower (average 30,0 ±2,51) than those who fail to get pregnant. Conclusions: vitrification as a cryopreservation method appears to be a promising technique and seems to be a good substitute for show freezing technique, due to its high-success rates, its reliability and execution speed, with replicable results.


Introdução: a vitrificação é uma técnica de criopreservação do grupo das chamadas técnicas "rápidas". Comparada com os processos tradicionais de congelação lenta, a vitrificação permite eliminar totalmente a formação de cristais tanto intra como extracelulares. Permite também colocar as células diretamente no crioprotetor e submergi-las em N2 líquido. Em todo o mundo sua aplicação vem crescendo exponencialmente e pode ser utilizada tanto com ovócitos como a embriões em qualquer estágio. Objetivos: revisão da técnica de vitrificação e apresentação da experiência de dois anos no Centro Iberoamericano de Reprodução Assistida, a primeira no Uruguay. Material e método: foram incluídas 17 pacientes que cujos embriões haviam sido vitrificados e desvitrificados. O método comercial Cryotop com soluções de vitrificação de Kitazato foi utilizado. Resultados: A média de embriões vitrificados foi de 2,71 (±0,69) por paciente com uma taxa de sobrevivência global dos embriões depois da desvitrificação de 93,4%. Com uma média de embriões transferidos de 2,41 (±0,62), a taxa final de gravidez foi de 47,1%. A idade das pacientes que engravidaram (média 30,0 ±2,51) era menor que a das que não engravidaram. Conclusões: a vitrificação se apresenta como um método de criopreservação prometedor e um bom substituto das técnicas de congelação lenta devido às altas taxas de sucesso, sua confiabilidade e rapidez para sua execução, com resultados reproduzíveis.


Assuntos
Criopreservação/métodos , Criopreservação/tendências
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