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1.
Int J Sports Med ; 25(7): 528-32, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15459834

RESUMO

19-Norandrosterone (19-NA) and 19-noretiocholanolone (19-NE) are the two main urinary indicators used to detect illegal use of nandrolone. Recent studies showed that 19-NA and 19-NE can be endogenously produced in non-treated humans. The concentrations were close to the threshold of the International Olympic Committee (IOC), i.e. 2 ng/ml for men and seem to increase after prolonged intense effort. Androgens are involved in the biosynthesis of estrogens and estrogen has a protective effect against skeletal muscle damage following eccentric exercise. Furthermore, the testicular tissue can synthesize 19-norandrogens from androgens, we hypothetisize that the 19-norandrogen production might be influenced by muscle damage following eccentric exercise. Therefore the purpose of this study is to examine if three different exercise methods will influence the urinary concentration of 19-NA and 19-NE in healthy young subjects. Fifteen amateur hockey players undertook a 30 min submaximal standardized exercise protocol. They were randomised for three different types of exercise, namely a cycle ergometer test (cyclic muscle activity), a treadmill test (concentric muscle activity), or a bench-steptest (eccentric muscle activity) at a target heart rate corresponding to 65 % (+/- 5 %) of Karvonen heart rate. Urine samples were obtained before the test and 60 min and 120 min after the end of exercise. Subjects completed a Likert scale of muscle soreness before and 12 h after exercise. 19-NA and 19-NE were determined by gas chromatography-tandem mass spectrometry (GC-MS-MS). Baseline urinary 19-NA and 19-NE concentrations were under limit of detection of 0.05 ng/ml, except for one sample (0.13 ng/ml). No 19-NA or 19-NE could be detected post exercise. In our experimental conditions, the exercise mode (eccentric or concentric) had no impact on 19-NA or 19-NE excretion. Our findings confirm that the current International Olympic Committee threshold level for nandrolone metabolites is sufficiently high to avoid false positive cases.


Assuntos
Dopagem Esportivo , Estranos/urina , Exercício Físico/fisiologia , Adulto , Anabolizantes/metabolismo , Anabolizantes/uso terapêutico , Ciclismo/fisiologia , Reações Falso-Positivas , Frequência Cardíaca , Humanos , Masculino , Nandrolona/metabolismo , Nandrolona/uso terapêutico , Valores de Referência , Corrida/fisiologia , Testículo/fisiologia , Levantamento de Peso/fisiologia
2.
Eur J Appl Physiol ; 91(2-3): 140-6, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-14523562

RESUMO

In overtrained athletes, several signs and symptoms have been associated with the imbalance between training and recovery. However, reliable diagnostic markers for distinguishing between well-trained, overreached (OR) and overtrained (OT) athletes are lacking. A hallmark feature of overtraining syndrome (OTS) is the inability to sustain intense exercise and recover for the next training or competition session. We therefore devised a test protocol utilizing two bouts of maximal work. With this test protocol we tried to establish a difference in hormonal responses between the training status of T and OR athletes. Seven well-trained cyclists participated in this study and were tested before and after a training camp. We also present the data of one OT motocross athlete who was clinically diagnosed as overtrained. All athletes performed two maximal exercise tests separated by 4 h. Blood was analyzed for cortisol, adrenocorticotrophic hormone (ACTH), growth hormone and prolactin (PRL). Performance decreased by 6% between the first and the second exercise test in the OR group and by 11% in the OT subject. Moreover, during the second exercise test there were more marked differences between the T and OR athletes; in particular, the OT subject did not show an increase in some of the hormonal responses. PRL increased only by 14% in the OT subject's second test and there was a 7% decrease in ACTH. The two exercise approach enables us to detect subtle performance decrements that will not be identified by one exercise trigger. The hormonal responses to the second exercise test were different between the T and OR athletes (the increase in the T group was higher than in the OR that was higher than in the OT). The results of the case presentation of an overtrained athlete provide evidence of an altered and dysfunctional hypothalamic-pituitary axis response to two bouts of maximal exercise. These findings can be used to develop markers for diagnosis of OTS and to begin to address the pathologic mechanism operative in the syndrome, as well as providing an outcome measure to evaluate possible therapeutic regimes.


Assuntos
Ciclismo/fisiologia , Teste de Esforço/métodos , Tolerância ao Exercício/fisiologia , Exercício Físico/fisiologia , Hormônios/sangue , Fadiga Muscular/fisiologia , Educação Física e Treinamento/métodos , Adaptação Fisiológica/fisiologia , Hormônio Adrenocorticotrópico/sangue , Adulto , Hormônio do Crescimento/sangue , Humanos , Hidrocortisona/sangue , Masculino , Prolactina/sangue , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Esportes/fisiologia
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