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1.
Nutrients ; 16(3)2024 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-38337659

RESUMEN

BACKGROUND: The consumption of dietary supplements (DS) is widespread among the general population and competitive athletes. However, only a few competitive athletes seek information from experts about the effects and use of DS. Furthermore, it is currently unknown whether certain sports have a higher affinity for DS than others. METHODS: This study aimed to identify differences between different sports categories and subgroups that may have a very high affinity for DS. For this purpose, competitive athletes were surveyed. The survey included the type of sport, the training frequency, the number of competitions, the consumption behaviour of five DS categories (general health, regeneration promotion, performance enhancement, booster, and weight loss) as well as personal data such as biological sex and age. Subsequently, correlations, configural frequencies (CFA), and multiple correspondence analyses (MCA) were used to identify subgroups with a high affinity of consumption behaviour. RESULTS: A total of 409 questionnaires could be evaluated. It was found that all DS categories except weight loss were related. In addition, it was observed that in sports from the power category and from the endurance category, there was even higher consumption behaviour than in other sports categories. Male power athletes in particular have a higher affinity for consuming DS than other subgroups. CONCLUSIONS: This study shows that there is a clear different consumption behaviour depending on the type of sport. Male power athletes in particular are the subgroup with the greatest consumption behaviour and therefore require special education on the effects and use of DS. This subgroup in particular should receive increased attention in counselling on DS to minimise the possible risks of DS use.


Asunto(s)
Doping en los Deportes , Deportes , Humanos , Masculino , Suplementos Dietéticos , Atletas , Pérdida de Peso
2.
Nutrients ; 15(6)2023 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-36986261

RESUMEN

The age-related loss of muscle mass promotes many impairments. Training and protein supplementation are suggested to prevent muscle wasting, but recommendations for all populations are not based on scientific evidence. This study combines protein/carbohydrate supplementation (PCS) and training for seniors and postmenopausal women. Project A: 51 postmenopausal women (PMW, 57.3 ± 3.0 years old) underwent health-oriented training (12 weeks, moderate-strength training + moderate-endurance training). The intervention group (IG) additionally received 110 g sour milk cheese (SMC) and toast. Project B: 25 women and 6 men (65.9 ± 4.9 years old) performed intense sling training (12 weeks). The IG additionally received 110 g SMC, toast, and buttermilk. Strength was tested before and after in both studies. Project A: there was significant increase in strength, no additional effect of PCS, and a reduction in body fat in the controls. Project B: there was significant increase in strength, significant additional effects of PCS for trunk strength, and a significant reduction in body weight. Combining training and PCS may counteract strength loss. Combined endurance/resistance training is recommended to PMW for whom the benefits of PCS are restricted. Aged subjects may benefit from PCS when training intensely, but these benefits may be strongly individual.


Asunto(s)
Fuerza Muscular , Entrenamiento de Fuerza , Masculino , Humanos , Femenino , Anciano , Persona de Mediana Edad , Posmenopausia , Carbohidratos/farmacología , Suplementos Dietéticos , Vitaminas/farmacología , Inmunoglobulinas/farmacología , Músculo Esquelético , Composición Corporal
3.
Nutrients ; 13(9)2021 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-34578906

RESUMEN

Cannabidiol supplements (CBD) are increasingly consumed by athletes to improve regeneration. However, the evidence for the pro-regenerative effects of CBD in sports is quite limited. Therefore, our aim was to investigate the effects of a single CBD supplementation in a six-arm placebo-controlled crossover study after resistance training on performance and muscle damage. Before and after the resistance training, one-repetition maximum in the back squat (1RM BS), countermovement jump (CMJ), and blood serum concentrations of creatine kinase (CK) and myoglobin (Myo) were measured in healthy, well-trained participants. 16 out of 21 participants completed the study and were included in the analysis. In 1RM BS, a significant decrease was observed after 24 h (p < 0.01) but not after 48 and 72 h. A significant group difference was detected after 72 h (p < 0.05; ES = 0.371). In CMJ, no significant changes were observed. The CK and Myo concentrations increased significantly after 24 h (CK: p < 0.001; Myo: p < 0.01), 48 h (CK: p < 0.001; Myo: p < 0.01) and 72 h (CK: p < 0.001; Myo: p < 0.001). After 72 h, significant group differences were observed for both muscle damage biomarkers (CK: p < 0.05 ES = 0.24; Myo: p < 0.05; ES = 0.21). The results show small but significant effects on muscle damage and recovery of squat performance after 72 h. However, more data are required for clearer statements concerning potential pro-regenerative effects of CBD supplementation after resistance training.


Asunto(s)
Cannabidiol/farmacología , Fuerza Muscular/efectos de los fármacos , Fuerza Muscular/fisiología , Músculo Esquelético/efectos de los fármacos , Músculo Esquelético/fisiología , Entrenamiento de Fuerza/métodos , Adulto , Cannabidiol/administración & dosificación , Estudios Cruzados , Suplementos Dietéticos , Método Doble Ciego , Alemania , Humanos , Masculino , Valores de Referencia , Adulto Joven
4.
Br J Sports Med ; 47(2): 109-14, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22554845

RESUMEN

The administration of musk extract, that is, ingredients obtained by extraction of the liquid secreted from the preputial gland or resulting grains of the male musk deer (eg, Moschus moschiferus), has been recommended in Traditional Chinese Medicine (TCM) applications and was listed in the Japanese pharmacopoeia for various indications requiring cardiovascular stimulation, anti-inflammatory medication or androgenic hormone therapy. Numerous steroidal components including cholesterol, 5α-androstane-3,17-dione, 5ß-androstane-3,17-dione, androsterone, etiocholanolone, epiandrosterone, 3ß-hydroxy-androst-5-en-17-one, androst-4-ene-3,17-dione and the corresponding urea adduct 3α-ureido-androst-4-en-17-one were characterised as natural ingredients of musk over several decades, implicating an issue concerning doping controls if used for the treatment of elite athletes. In the present study, the impact of musk extract administration on sports drug testing results of five females competing in an international sporting event is reported. In the course of routine doping controls, adverse analytical findings concerning the athletes' steroid profile, corroborated by isotope-ratio mass spectrometry (IRMS) data, were obtained. The athletes' medical advisors admitted the prescription of TCM-based musk pod preparations and provided musk pod samples for comparison purposes to clarify the antidoping rule violation. Steroid profiles, IRMS results, literature data and a musk sample obtained from a living musk deer of a local zoo conclusively demonstrated the use of musk pod extracts in all cases which, however, represented a doping offence as prohibited anabolic-androgenic steroids were administered.


Asunto(s)
Doping en los Deportes/prevención & control , Ácidos Grasos Monoinsaturados/administración & dosificación , Medicina Tradicional China , Esteroides/administración & dosificación , Detección de Abuso de Sustancias/métodos , Extractos de Tejidos/administración & dosificación , Animales , Ciervos , Doping en los Deportes/métodos , Ácidos Grasos Monoinsaturados/química , Ácidos Grasos Monoinsaturados/orina , Femenino , Humanos , Espectrometría de Masas/métodos , Esteroides/química , Esteroides/orina , Extractos de Tejidos/química , Extractos de Tejidos/orina
5.
Endocrinol Metab Clin North Am ; 39(1): 45-57, viii, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20122449

RESUMEN

Testosterone is the principal male sex hormone. As with all natural steroids, it is biosynthesized from cholesterol. Phase I metabolism employs some very specific enzymes and pathways. Phase II metabolism and excretion follow more general patterns. The effects of testosterone are twofold: anabolic and androgenic. Because of its anabolic effects, testosterone is frequently abused in sports. Because of its endogenous nature, testosterone doping is difficult to detect. The standard procedure is based on the evaluation of the urinary steroid profile. Conspicuous samples then are submitted to compound-specific (13)C/(12)C analysis. Synthetic and endogenous steroids differ in this measure. Numerous xenobiotic compounds have been derived from testosterone. The modifications typically aim at a reduction of the androgenic properties while maintaining the anabolic potential. Most of these compounds have been withdrawn from the legal market. However, they are found to be illicitly added to otherwise inefficient nutritional supplements. These products represent a major problem to doping control. Recently, clinical trials with selective androgen receptor modulators have been started.


Asunto(s)
Anabolizantes , Doping en los Deportes , Anabolizantes/administración & dosificación , Anabolizantes/efectos adversos , Anabolizantes/síntesis química , Atletas , Rendimiento Atlético/fisiología , Deshidroepiandrosterona/administración & dosificación , Deshidroepiandrosterona/efectos adversos , Suplementos Dietéticos , Doping en los Deportes/prevención & control , Femenino , Cromatografía de Gases y Espectrometría de Masas , Humanos , Isótopos/análisis , Masculino , Nandrolona/administración & dosificación , Testosterona/administración & dosificación , Testosterona/efectos adversos , Testosterona/fisiología
6.
Drug Test Anal ; 1(11-12): 587-95, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20355175

RESUMEN

Adrenosterone (androst-4-ene-3,11,17-trione, 11-oxoandrostenedione) is an endogenous steroid hormone that has been promoted as a dietary supplement capable of reducing body fat and increasing muscle mass. It is proposed that adrenosterone may function as an inhibitor of the 11beta-hydroxysteroid dehydrogenase type 1 enzyme (11beta-HSD1), which is primarily responsible for reactivation of cortisol from cortisone. The urinary metabolism of adrenosterone was investigated, after a single oral administration in two male subjects, by gas chromatography-mass spectrometry (GC-MS) and gas chromatography-combustion-isotope ratio mass spectrometry (GC-C-IRMS). Substantially increased excretion of 11beta-hydroxyandrosterone, 11beta-hydroxyetiocholanolone, 11-oxoandrosterone and 11-oxoetiocholanolone was observed. Minor metabolites such as 3alpha,17beta-dihydroxy-5beta-androstan-11-one, 3alpha-hydroxyandrost-4-ene-11,17-dione and 3alpha,11beta-dihydroxyandrost-4-en-17-one were also identified. The exogenous origin of the most abundant adrenosterone metabolites was confirmed by GC-C-IRMS according to World Anti-Doping Agency criteria. Through analysis of a reference population data set obtained from urine samples provided by elite athlete volunteers (n = 85), GC-MS doping control screening criteria are proposed: 11beta-hydroxyandrosterone concentration greater than 10 000 ng/mL (specific gravity adjusted to 1.020) or 11beta-hydroxyandrosterone/11beta-hydroxyetiocholanolone ratio greater than 20.Urine samples fulfilling these screening criteria may be subjected to GC-C-IRMS analysis for confirmation of adrenosterone administration.


Asunto(s)
Androstenos/normas , Androstenos/orina , Isótopos de Carbono/orina , Cromatografía de Gases y Espectrometría de Masas/métodos , Esteroides/normas , Esteroides/orina , Detección de Abuso de Sustancias/métodos , Androstenos/farmacocinética , Atletas , Suplementos Dietéticos/análisis , Doping en los Deportes , Humanos , Masculino , Valores de Referencia , Esteroides/farmacocinética , Detección de Abuso de Sustancias/normas
7.
Analyst ; 131(9): 1021-6, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17047802

RESUMEN

On the one hand, 19-norandrosterone (NA) is the most abundant metabolite of the synthetic anabolic steroid 19-nortestosterone and related prohormones. On the other hand, small amounts are biosynthesized by pregnant women and further evidence exists for physiological origin of this compound. The World Anti-Doping Agency (WADA) formerly introduced threshold concentrations of 2 or 5 ng of NA per ml of urine to discriminate 19-nortestosterone abuse from biosynthetic origin. Recent findings showed however, that formation of NA resulting in concentrations in the range of the threshold levels might be due to demethylation of androsterone in urine, and the WADA 2006 Prohibited List has defined NA as endogenous steroid. To elucidate the endogenous or exogenous origin of NA, (13)C/(12)C-analysis is the method of choice since synthetic 19-nortestosterone is derived from C(3)-plants by partial synthesis and shows delta(13)C(VPDB)-values of around -28 per thousand. Endogenous steroids are less depleted in (13)C due to a dietary mixture of C(3)- and C(4)-plants. An extensive cleanup based on two high performance liquid chromatography cleanup steps was applied to quality control and doping control samples, which contained NA in concentrations down to 2 ng per ml of urine. (13)C/(12)C-ratios of NA, androsterone and etiocholanolone were measured by gas chromatography/combustion/isotope ratio mass spectrometry. By comparing delta(13)C(VPDB)-values of androsterone as endogenous reference compound with NA, the origin of NA in doping control samples was determined as either endogenous or exogenous.


Asunto(s)
Isótopos de Carbono/orina , Doping en los Deportes , Estranos/orina , Detección de Abuso de Sustancias/métodos , Etiocolanolona/orina , Femenino , Cromatografía de Gases y Espectrometría de Masas/métodos , Humanos , Masculino , Nandrolona/orina , Extractos Vegetales
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