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1.
Int J Sports Med ; 39(9): 712-719, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29940669

RESUMO

WADA has banned dehydroepiandrosterone (DHEA) but its ergogenic effect in female athletes has never been investigated. The aim of this study was to determine whether short-term DHEA intake would improve performance during a supramaximal field exercise in healthy young recreationally trained women. Its impact on body composition, metabolic responses was also measured. Eleven young female volunteers completed four running-based anaerobic sprint tests: just before and after treatment with either oral placebo or DHEA (100 mg/day/28days), following a double-blind and randomized protocol. Bioelectrical impedance assessed body composition. At rest and after passive recovery, blood samples were collected for lactate measurement and saliva samples for DHEA, testosterone and cortisol analysis. There was no significant difference in body composition or performance parameters after DHEA administration, despite a tendency toward increased peak power and decreased fat mass. However, DHEA treatment induced a very marked increase in saliva DHEA and testosterone concentrations (p<0.001), with no change in cortisol or lactate levels. In conclusion, short-term DHEA administration did not improve performance or have an anabolic effect in young female recreationally trained athletes, despite the increase in androgenic hormones. Further studies are needed to determine whether a higher daily dose would generate an ergogenic effect during anaerobic exercise.


Assuntos
Desempenho Atlético/fisiologia , Desidroepiandrosterona/administração & dosagem , Exercício Físico/fisiologia , Substâncias para Melhoria do Desempenho/administração & dosagem , Composição Corporal/efeitos dos fármacos , Estudos Cross-Over , Desidroepiandrosterona/metabolismo , Método Duplo-Cego , Esquema de Medicação , Teste de Esforço , Feminino , Frequência Cardíaca/fisiologia , Humanos , Hidrocortisona/metabolismo , Ácido Láctico/sangue , Substâncias para Melhoria do Desempenho/metabolismo , Saliva/metabolismo , Testosterona/metabolismo , Adulto Jovem
2.
Endocrine ; 59(3): 538-546, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29322301

RESUMO

BACKGROUND: Dehydroepiandrosterone (DHEA) figures on the World Anti-Doping Agency list of prohibited substances in sport because it is assumed that athletes expect a significant increase in testosterone through DHEA administration. The literature on the hormonal effects of DHEA intake nevertheless appears to be very scant in healthy young subjects, especially women. PURPOSE: We examined the effects of DHEA on adrenal and gonadal hormones, IGF1 and free T3 in healthy young male and female recreationally trained volunteers. METHODS: The study followed a double-blind, randomized-order crossover design. Lean healthy young men (n = 10) and women (n = 11), with all women using oral contraceptives, were treated daily with 100 mg of DHEA and placebo for 4 weeks. DHEA, DHEA-sulfate (DHEA-S), androstenedione, total testosterone (Tes), dihydrotestosterone (DHT), SHBG, estrone, cortisol, IGF1, and free T3 were measured before, in the middle and at the end of each treatment, as were blood glucose, liver transaminases and lipid status. RESULTS: We observed a significant increase in DHEA, DHEA-S, androstenedione, Tes, DHT, and estrone in both men and women in the middle and at the end of DHEA treatment, but the increase in Tes was more marked in women (p < 0.001) than men (p < 0.05). No changes were found in the other parameters, irrespective of gender. CONCLUSION: In young athletes, DHEA administration induces significant blood hormonal changes, some modulated by gender, which can be used as biomarkers of doping.


Assuntos
Androgênios/sangue , Atletas , Desidroepiandrosterona/administração & dosagem , Hidrocortisona/sangue , Fator de Crescimento Insulin-Like I/metabolismo , Tri-Iodotironina/sangue , Androstenodiona/sangue , Estudos Cross-Over , Desidroepiandrosterona/sangue , Sulfato de Desidroepiandrosterona/sangue , Di-Hidrotestosterona/sangue , Método Duplo-Cego , Estrona/sangue , Feminino , Humanos , Masculino , Fatores Sexuais , Globulina de Ligação a Hormônio Sexual , Testosterona/sangue , Adulto Jovem
3.
Steroids ; 86: 10-5, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24793567

RESUMO

All systemically administered glucocorticoids (GC) are prohibited in-competition, because of the potential ergogenic effects. Although short-term GC intake has been shown to improve performance during submaximal exercise, literature on its impact during brief intense exercise appears to be very scant. The purpose of this study was to examine the ergogenic and metabolic effects of prednisone during repeated bouts of high-intensity exercise. In a double-blind randomized protocol, ten recreational male athletes followed two 1-week treatments (Cor: prednisone, 60mg/day or Pla: placebo). At the end of each treatment, they hopped on their dominant leg for 30s three times consecutively and then hopped until exhaustion, with intervals of 5min of passive recovery. Blood and saliva samples were collected at rest and 3min after each exercise bout to determine the lactate, interleukin-6, interleukin-10, TNF-alpha, DHEA and testosterone values. The absolute peak force of the dominant leg was significantly increased by Cor but only during the first 30-s hopping bout (p<0.05), whereas time to exhaustion was not significantly changed after Cor treatment vs Pla (Pla: 119.9±24.7; Cor: 123.1±29.5s). Cor intake lowered basal and end-exercise plasma interleukin-6 and saliva DHEA (p<0.01) and increased interleukin-10 (p<0.01), whereas no significant change was found in blood lactate and TNF-alpha or saliva testosterone between Pla and Cor. According to these data, short-term glucocorticoid intake did not improve endurance performance during repeated bouts of high-intensity exercise, despite the significant initial increase in absolute peak force and anti-inflammatory effect.


Assuntos
Metabolismo Energético/efeitos dos fármacos , Exercício Físico/fisiologia , Glucocorticoides/administração & dosagem , Glucocorticoides/farmacologia , Administração Oral , Adulto , Estudos Cross-Over , Método Duplo-Cego , Teste de Esforço , Glucocorticoides/sangue , Voluntários Saudáveis , Humanos , Masculino , Adulto Jovem
4.
Steroids ; 77(13): 1339-44, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22917632

RESUMO

The purpose of this study was to assess changes in the steroid hormone levels of elite athletes during an international powerlifting competition. Baseline cortisol, DHEA and testosterone were determined in saliva samples in 19 (8 men, 11 women) junior and sub-junior athletes on the day before competition, and then on the competition day during the official weighing and in the hour after competition. Performance was determined by total output and the Wilks formula. No change in saliva steroid concentrations was observed between samples collected on the day before competition and the weighing samples. There was no gender effect on cortisol concentrations but saliva testosterone levels were always significantly higher in men than in women (p<0.01), as was end-competition DHEA (p<0.05). Cortisol and DHEA were significantly increased in male and female athletes after the competition (respectively, p<0.01 and p<0.05), whereas end-competition testosterone concentrations were only significantly increased in men (p<0.01). Significant relationships were demonstrated between performance and end-competition cortisol levels in women and end-competition testosterone levels in men. These data indicate that workouts during an international powerlifting competition produce a significant increase in adrenal steroid hormones in both genders, with an increase in male gonadal steroid hormone. Further studies are necessary to examine the changes in oestradiol and progesterone in women and their potential impact on performance during international powerlifting competition.


Assuntos
Atletas , Hormônios/metabolismo , Internacionalidade , Esteroides/metabolismo , Levantamento de Peso , Exercício Físico , Feminino , Humanos , Masculino , Descanso , Saliva/metabolismo , Fatores de Tempo , Adulto Jovem
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