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1.
J Clin Endocrinol Metab ; 107(3): 649-659, 2022 02 17.
Artículo en Inglés | MEDLINE | ID: mdl-34726230

RESUMEN

CONTEXT: Because of its anabolic and lipolytic properties, growth hormone (GH) use is prohibited in sport. Two methods based on population-derived decision limits are currently used to detect human GH (hGH) abuse: the hGH Biomarkers Test and the Isoforms Differential Immunoassay. OBJECTIVE: We tested the hypothesis that longitudinal profiling of hGH biomarkers through application of the Athlete Biological Passport (ABP) has the potential to flag hGH abuse. METHODS: Insulin-like growth factor 1 (IGF-1) and procollagen III peptide (P-III-NP) distributions were obtained from 7 years of anti-doping data in elite athletes (n = 11 455) and applied as priors to analyze individual profiles from an hGH administration study in recreational athletes (n = 35). An open-label, randomized, single-site, placebo-controlled administration study was carried out with individuals randomly assigned to 4 arms: placebo, or 3 different doses of recombinant hGH. Serum samples were analyzed for IGF-1, P-III-NP, and hGH isoforms and the performance of a longitudinal, ABP-based approach was evaluated. RESULTS: An ABP-based approach set at a 99% specificity level flagged 20/27 individuals receiving hGH treatment, including 17/27 individuals after cessation of the treatment. ABP sensitivity ranged from 12.5% to 71.4% across the hGH concentrations tested following 7 days of treatment, peaking at 57.1% to 100% after 21 days of treatment, and was maintained between 37.5% and 71.4% for the low and high dose groups 1 week after cessation of treatment. CONCLUSION: These findings demonstrate that longitudinal profiling of hGH biomarkers can provide suitable performance characteristics for use in anti-doping programs.


Asunto(s)
Doping en los Deportes/prevención & control , Hormona de Crecimiento Humana/administración & dosificación , Sustancias para Mejorar el Rendimiento/administración & dosificación , Detección de Abuso de Sustancias/métodos , Adulto , Atletas/estadística & datos numéricos , Biomarcadores/sangre , Femenino , Voluntarios Sanos , Hormona de Crecimiento Humana/sangre , Humanos , Factor I del Crecimiento Similar a la Insulina/análisis , Masculino , Fragmentos de Péptidos/sangre , Sustancias para Mejorar el Rendimiento/sangre , Procolágeno/sangre
2.
J Int Soc Sports Nutr ; 18(1): 15, 2021 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-33588872

RESUMEN

BACKGROUND: chicken meat extract is a popular functional food in Asia. It is rich in the bioactive compounds carnosine and anserine, two histidine-containing dipeptides (HCD). Studies suggest that acute pre-exercise ingestion of chicken extracts has important applications towards exercise performance and fatigue control, but the evidence is equivocal. This study aimed to evaluate the ergogenic potential of the pre-exercise ingestion of a homemade chicken broth (CB) vs a placebo soup on a short-lasting, high-intensity cycling exercise. METHODS: fourteen men participated in this double-blind, placebo-controlled, crossover intervention study. Subjects ingested either CB, thereby receiving 46.4 mg/kg body weight of HCD, or a placebo soup (similar in taste without HCD) 40 min before an 8 min cycling time trial (TT) was performed. Venous blood samples were collected at arrival (fasted), before exercise and at 5 min recovery. Plasma HCD were measured with UPLC-MS/MS and glutathione (in red blood cells) was measured through HPLC. Capillary blood samples were collected at different timepoints before and after exercise. RESULTS: a significant improvement (p = 0.033; 5.2%) of the 8 min TT mean power was observed after CB supplementation compared to placebo. Post-exercise plasma carnosine (p <  0.05) and anserine (p <  0.001) was significantly increased after CB supplementation and not following placebo. No significant effect of CB supplementation was observed either on blood glutathione levels, nor on capillary blood analysis. CONCLUSIONS: oral CB supplementation improved the 8 min TT performance albeit it did not affect the acid-base balance or oxidative status parameters. Further research should unravel the potential role and mechanisms of HCD, present in CB, in this ergogenic approach.


Asunto(s)
Anserina/farmacología , Ciclismo/fisiología , Carnosina/farmacología , Carne , Sustancias para Mejorar el Rendimiento/farmacología , Equilibrio Ácido-Base , Análisis de Varianza , Animales , Anserina/administración & dosificación , Anserina/sangre , Rendimiento Atlético , Capilares , Carnosina/administración & dosificación , Carnosina/sangre , Pollos , Cromatografía Liquida , Estudios Cruzados , Método Doble Ciego , Alimentos , Glutatión/sangre , Humanos , Masculino , Sustancias para Mejorar el Rendimiento/administración & dosificación , Sustancias para Mejorar el Rendimiento/sangre , Placebos/administración & dosificación , Espectrometría de Masas en Tándem , Factores de Tiempo
3.
Drug Test Anal ; 13(2): 369-385, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32959959

RESUMEN

AC-262536 is one of a number of selective androgen receptor modulators that are being developed by the pharmaceutical industry for treatment of a range of clinical conditions including androgen replacement therapy. Though not available therapeutically, selective androgen receptor modulators are widely available to purchase online as (illegal) supplement products. The growth- and bone-promoting effects, along with fewer associated negative side effects compared with anabolic-androgenic steroids, make these compounds a significant threat with regard to doping control in sport. The aim of this study was to investigate the metabolism of AC-262536 in the horse following in vitro incubation and oral administration to two Thoroughbred horses, in order to identify the most appropriate analytical targets for doping control laboratories. Urine, plasma and hair samples were collected and analysed for parent drug and metabolites. Liquid chromatography-high-resolution mass spectrometry was used for in vitro metabolite identification and in urine and plasma samples. Nine phase I metabolites were identified in vitro; four of these were subsequently detected in urine and three in plasma, alongside the parent compound in both matrices. In both urine and plasma samples, the longest detection window was observed for an epimer of the parent compound, which is suggested as the best target for detection of AC-262536 administration. AC-262536 and metabolites were found to be primarily glucuronide conjugates in both urine and plasma. Liquid chromatography-tandem mass spectrometry analysis of post-administration hair samples indicated incorporation of parent AC-262536 into the hair following oral administration. No metabolites were detected in the hair.


Asunto(s)
Compuestos de Azabiciclo/metabolismo , Caballos/metabolismo , Naftalenos/metabolismo , Sustancias para Mejorar el Rendimiento/metabolismo , Administración Oral , Animales , Compuestos de Azabiciclo/administración & dosificación , Compuestos de Azabiciclo/sangre , Compuestos de Azabiciclo/orina , Cromatografía Liquida , Cabello/química , Caballos/sangre , Caballos/orina , Naftalenos/administración & dosificación , Naftalenos/sangre , Naftalenos/orina , Sustancias para Mejorar el Rendimiento/administración & dosificación , Sustancias para Mejorar el Rendimiento/sangre , Sustancias para Mejorar el Rendimiento/orina , Receptores Androgénicos/metabolismo , Detección de Abuso de Sustancias , Espectrometría de Masas en Tándem
4.
J Int Soc Sports Nutr ; 17(1): 47, 2020 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-32907591

RESUMEN

BACKGROUND: An acute bout of exercise induces an inflammatory response characterized by increases in several cytokines. Caffeine ingestion could modify this inflammatory response. The aim of this study was to determine the effects of caffeine supplementation on plasma levels of cytokines, mainly IL-10 and IL-6, in response to exercise. METHODS: In a randomized, crossover, double-blinded study design, thirteen healthy, well-trained recreational male athletes performed, on two different occasions, a treadmill exercise test (60 min at 70% VO2max) after ingesting 6 mg/kg body mass of caffeine or placebo. Blood samples were taken before exercising, immediately after finishing and 2 h after finishing the exercise. Plasma concentrations of IL-10, IL-6, IL-1ß, IL-1ra, IL-4, IL-8, IL-12 and IFN-γ, adrenaline, cortisol and cyclic adenosine monophosphate (cAMP) were determined. The capacity of whole blood cultures to produce cytokines in response to endotoxin (LPS) was also determined. Changes in blood variables were analyzed using a time (pre-exercise, post-exercise, recovery) x condition (caffeine, placebo) within-between subjects ANOVA with repeated measures. RESULTS: Caffeine supplementation induced higher adrenaline levels in the supplemented participants after exercise (257.3 ± 53.2 vs. 134.0 ± 25.7 pg·mL- 1, p = 0.03) and higher cortisol levels after recovery (46.4 ± 8.5 vs. 32.3 ± 5.6 pg·mL- 1, p = 0.007), but it did not influence plasma cAMP levels (p = 0.327). The exercise test induced significant increases in IL-10, IL-6, IL-1ra, IL-4, IL-8, IL-12 and IFN-γ plasma levels, with IL-6 and IL-10 levels remaining high after recovery. Caffeine supplementation influenced only IL-6 (3.04 ± 0.40 vs. 3.89 ± 0.62 pg·mL- 1, p = 0.003) and IL-10 (2.42 ± 0.54 vs. 3.47 ± 0.72 pg·mL- 1, p = 0.01) levels, with higher concentrations after exercise in the supplemented condition. No effect of caffeine was observed on the in vitro stimulated cytokine production. CONCLUSIONS: The results of the present study indicate a significant influence of caffeine supplementation increasing the response to exercise of two essential cytokines such as IL-6 and IL-10. However, caffeine did not influence changes in the plasma levels of other cytokines measured and the in vitro-stimulated cytokine production.


Asunto(s)
Cafeína/administración & dosificación , Ejercicio Físico/fisiología , Interleucina-10/sangre , Interleucina-6/sangre , Sustancias para Mejorar el Rendimiento/administración & dosificación , Adulto , Cafeína/sangre , Estudios Cruzados , AMP Cíclico/sangre , Método Doble Ciego , Epinefrina/sangre , Prueba de Esfuerzo/métodos , Humanos , Hidrocortisona/sangre , Interferón gamma/sangre , Interleucinas/sangre , Recuento de Leucocitos , Masculino , Sustancias para Mejorar el Rendimiento/sangre
5.
Scand J Med Sci Sports ; 30(11): 2116-2129, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32681596

RESUMEN

The effects of 4 mg·kg-1 caffeine ingestion on strength and power were investigated for the first time, in resistance-trained females during the early follicular phase utilizing a randomized, double-blind, placebo-controlled, crossover design. Fifteen females (29.8 ± 4.0 years, 63.8 ± 5.5 kg [mean ± SD]) ingested caffeine or placebo 60 minutes before completing a test battery separated by 72 hours. One-repetition maximum (1RM), repetitions to failure (RTF) at 60% of 1RM, was assessed in the squat and bench press. Maximal voluntary contraction torque (MVC) and rate of force development (RFD) were measured during isometric knee extensions, while utilizing interpolated twitch technique to measure voluntary muscle activation. Maximal power and jump height were assessed during countermovement jumps (CMJ). Caffeine metabolites were measured in plasma. Adverse effects were registered after each trial. Caffeine significantly improved squat (4.5 ± 1.9%, effect size [ES]: 0.25) and bench press 1RM (3.3 ± 1.4%, ES: 0.20), and squat (15.9 ± 17.9%, ES: 0.31) and bench press RTF (9.8 ± 13.6%, ES: 0.31), compared to placebo. MVC torque (4.6 ± 7.3%, ES: 0.26), CMJ height (7.6 ± 4.0%, ES: 0.50), and power (3.8 ± 2.2%, ES: 0.24) were also significantly increased with caffeine. There were no differences in RFD or muscle activation. Plasma [caffeine] was significantly increased throughout the protocol, and mild side effects of caffeine were experienced by only 3 participants. This study demonstrated that 4 mg·kg-1 caffeine ingestion enhanced maximal strength, power, and muscular endurance in resistance-trained and caffeine-habituated females during the early follicular phase, with few adverse effects. Female strength and power athletes may consider using this dose pre-competition and -training as an effective ergogenic aid.


Asunto(s)
Bebidas , Cafeína/administración & dosificación , Fase Folicular/fisiología , Fuerza Muscular/efectos de los fármacos , Sustancias para Mejorar el Rendimiento/administración & dosificación , Entrenamiento de Fuerza , Adulto , Cafeína/efectos adversos , Cafeína/sangre , Estudios Cruzados , Método Doble Ciego , Femenino , Humanos , Contracción Isométrica , Rodilla/fisiología , Mialgia/fisiopatología , Percepción/fisiología , Sustancias para Mejorar el Rendimiento/efectos adversos , Sustancias para Mejorar el Rendimiento/sangre , Esfuerzo Físico/fisiología , Ejercicio Pliométrico , Entrenamiento de Fuerza/métodos , Levantamiento de Peso/fisiología
6.
Int J Sport Nutr Exerc Metab ; 30(5): 330-337, 2020 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-32668408

RESUMEN

Ergogenic strategies have been studied to alleviate muscle fatigue and improve sports performance. Sodium bicarbonate (NaHCO3) has improved repeated sprint performance in adult team-sports players, but the effect for adolescents is unknown. The aim of the present study was to evaluate the effect of NaHCO3 supplementation on repeated sprint performance in semiprofessional adolescent soccer players. In a double-blind, placebo-controlled, crossover trial, 15 male semiprofessional adolescent soccer players (15 ± 1 years; body fat 10.7 ± 1.3%) ingested NaHCO3 or a placebo (sodium chloride) 90 min before performing the running anaerobic sprint test (RAST). A countermovement jump was performed before and after the RAST, and ratings of perceived exertion, blood parameters (potential hydrogen and bicarbonate concentration), and fatigue index were also evaluated. Supplementation with NaHCO3 promoted alkalosis, as demonstrated by the increase from the baseline to preexercise, compared with the placebo (potential hydrogen: +0.07 ± 0.01 vs. -0.00 ± 0.01, p < .001 and bicarbonate: +3.44 ± 0.38 vs. -1.45 ± 0.31 mmol/L, p < .001); however, this change did not translate into an improvement in RAST total time (32.12 ± 0.30 vs. 33.31 ± 0.41 s, p = .553); fatigue index (5.44 ± 0.64 vs. 6.28 ± 0.64 W/s, p = .263); ratings of perceived exertion (7.60 ± 0.33 vs. 7.80 ± 0.10 units, p = .525); countermovement jump pre-RAST (32.21 ± 3.35 vs. 32.05 ± 3.51 cm, p = .383); or countermovement jump post-RAST (31.70 ± 0.78 vs. 32.74 ± 1.11 cm, p = .696). Acute NaHCO3 supplementation did not reduce muscle fatigue or improve RAST performance in semiprofessional adolescent soccer players. More work assessing supplementation in this age group is required to increase understanding in the area.


Asunto(s)
Rendimiento Atlético/fisiología , Sustancias para Mejorar el Rendimiento/administración & dosificación , Carrera/fisiología , Fútbol/fisiología , Bicarbonato de Sodio/administración & dosificación , Adolescente , Estudios Cruzados , Método Doble Ciego , Prueba de Esfuerzo , Humanos , Concentración de Iones de Hidrógeno , Fatiga Muscular , Fuerza Muscular , Sustancias para Mejorar el Rendimiento/sangre , Bicarbonato de Sodio/sangre
7.
Drug Test Anal ; 12(6): 704-710, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32180361

RESUMEN

Dried blood spots (DBS) have been considered as complementary matrix in sports drug testing for many years. Especially concerning substances prohibited in-competition only, the added value of DBS collected concomitantly with routine doping control urine samples has been debated, and an increasing potential of DBS has been discussed in the scientific literature. To which extent and under which prerequisites DBS can contribute to enhanced anti-doping efforts is currently evaluated. As a proof-of-principle, two analytical applications, one targeting cocaine/benzoyl ecgonine and the other prednisone/prednisolone, are presented in this perspective to indicate potential added value but also presently existing limitations of the DBS approach.


Asunto(s)
Doping en los Deportes , Pruebas con Sangre Seca/métodos , Detección de Abuso de Sustancias/métodos , Cocaína/análogos & derivados , Cocaína/sangre , Cocaína/orina , Humanos , Sustancias para Mejorar el Rendimiento/sangre , Preparaciones Farmacéuticas/sangre , Preparaciones Farmacéuticas/orina , Proyectos Piloto , Prednisolona/sangre , Prednisolona/orina , Prednisona/sangre , Prednisona/orina , Estándares de Referencia , Deportes
8.
J Anal Toxicol ; 44(5): 490-498, 2020 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-32020176

RESUMEN

Recently, an increased tendency to use various metals has been observed in the sports competition fields. Many of these metals and their organic complexes reportedly have good pharmacologic, therapeutic and performance-enhancement uses; they are banned or recommended as controlled medications in competitive sports. The objective of this research was to determine the concentration of pharmacologically relevant metals in urine samples collected from racehorses at various sport events, develop a method and assess the concentrations of above metals using inductively coupled plasma mass spectrometry (ICP-MS). Seven alkali-alkaline earth metals (lithium, sodium, potassium, magnesium, calcium, strontium and barium) and six heavy metals (chromium, cobalt, copper, zinc, arsenic and selenium) were studied in detail. To compare and confirm the concentrations of these metals, the screening was carried out on the basis of region and sex of the animal. ICP-MS provides extremely high sensitivity that enables the determination of the metals at very low concentration from complex biological matrices. From the research, it is clear that irrespective of sex and region the concentration of metal is very high in some samples, might be accidental or intentional doping to improve sporting performances. This research work is of significant importance in setting threshold values for screening metals in race day samples in order to avoid potential harmful effects on athletes and the depth of malpractices, it can bring to sports.


Asunto(s)
Doping en los Deportes , Caballos/metabolismo , Metales/orina , Sustancias para Mejorar el Rendimiento/orina , Detección de Abuso de Sustancias/métodos , Oligoelementos/orina , Animales , Arsénico , Cromo , Cobalto , Sustancias para Mejorar el Rendimiento/sangre , Potasio , Selenio , Sodio , Espectrofotometría Atómica , Oligoelementos/sangre
9.
Drug Test Anal ; 12(2): 247-260, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31655494

RESUMEN

LGD-4033 is one of a number of selective androgen receptor modulators (SARMs) that are being developed by the pharmaceutical industry to provide the therapeutic benefits of anabolic androgenic steroids, without the less desirable side effects. Though not available therapeutically, SARMs are available for purchase online as supplement products. The potential for performance enhancing effects associated with these products makes them a significant concern with regards to doping control in sports. The purpose of this study was to investigate the metabolism of LGD-4033 in the horse following oral administration, in order to identify the most appropriate analytical targets for doping control laboratories. LGD-4033 was orally administered to two Thoroughbred horses and urine, plasma and hair samples were collected and analysed for parent drug and metabolites. LC-HRMS was used for metabolite identification in urine and plasma. Eight metabolites were detected in urine, five of which were excreted only as phase II conjugates, with the longest detection time being observed for di- and tri-hydroxylated metabolites. The parent compound could only be detected in urine in the conjugated fraction. Seven metabolites were detected in plasma along with the parent compound where mono-hydroxylated metabolites provided the longest duration of detection. Preliminary investigations with hair samples using LC-MS/MS analysis indicated the presence of trace amounts of the parent compound and one of the mono-hydroxylated metabolites. In vitro incubation of LGD-4033 with equine liver microsomes was also performed for comparison, yielding 11 phase I metabolites. All of the metabolites observed in vivo were also observed in vitro.


Asunto(s)
Caballos/metabolismo , Nitrilos/metabolismo , Sustancias para Mejorar el Rendimiento/metabolismo , Pirrolidinas/metabolismo , Administración Oral , Pelaje de Animal/química , Pelaje de Animal/metabolismo , Animales , Doping en los Deportes , Caballos/sangre , Caballos/orina , Nitrilos/administración & dosificación , Nitrilos/sangre , Nitrilos/orina , Sustancias para Mejorar el Rendimiento/administración & dosificación , Sustancias para Mejorar el Rendimiento/sangre , Sustancias para Mejorar el Rendimiento/orina , Pirrolidinas/administración & dosificación , Pirrolidinas/sangre , Pirrolidinas/orina , Receptores Androgénicos/metabolismo , Detección de Abuso de Sustancias/métodos , Espectrometría de Masas en Tándem/métodos
10.
Drug Test Anal ; 12(1): 7-26, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31724288

RESUMEN

Within the complex construct of today's antidoping work, continuously updated routine doping controls, as well as advancements in sampling and analysis have been of particular relevance and importance. New analytes of existing classes of prohibited substances are frequently included into sports drug testing assays, analytical approaches are optimized to allow for better sensitivities, selectivity, and/or faster turnaround times, and research dedicated to addressing analytical issues concerning scenarios of both (potentially) inadvertent doping and new emerging doping agents is constantly conducted. By way of reviewing and summarizing, this annual banned-substance review evaluates the literature published between October 2018 and September 2019 offering an in-depth evaluation of developments in these arenas and their potential application to substances reported in WADA's 2019 Prohibited List.


Asunto(s)
Doping en los Deportes , Detección de Abuso de Sustancias/métodos , Anabolizantes/análisis , Anabolizantes/sangre , Anabolizantes/orina , Animales , Hormonas/análisis , Hormonas/sangre , Hormonas/orina , Humanos , Péptidos y Proteínas de Señalización Intercelular/análisis , Péptidos y Proteínas de Señalización Intercelular/sangre , Péptidos y Proteínas de Señalización Intercelular/orina , Espectrometría de Masas/métodos , Sustancias para Mejorar el Rendimiento/análisis , Sustancias para Mejorar el Rendimiento/sangre , Sustancias para Mejorar el Rendimiento/orina , Manejo de Especímenes/métodos , Esteroides/análisis , Esteroides/sangre , Esteroides/orina
11.
Int J Sports Med ; 40(11): 711-716, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31434137

RESUMEN

The purpose of this study was to evaluate whether NaHCO3, administered via a 9-h stacked loading protocol (i.e. repeated supplementation with small doses in order to obtain a gradual increase in blood [HCO3 -]), has an ergogenic effect on repeated all-out exercise. Twelve physically active males were randomly assigned to receive either NaHCO3 (BIC) or placebo (PL) in a double-blind cross-over design. NaHCO3 supplementation was divided in three identical 3-h cycles: a 6.3 g bolus at the start, followed by 2.1 g doses at +1-h and +2-h, yielding a total NaHCO3 intake of 0.4 g·kg-1 BM over 9-h. At the end of each cycle, participants performed 2-min all-out cycling. Capillary blood samples were analyzed for [HCO3 -], pH and [La-]. Pre-exercise blood [HCO3 -] in PL decreased from 25.6±0.2 mmol·L-1 in bout 1 to 23.6±0.2 mmol·L-1 in bout 4, while increasing from 25.5±0.2 to 31.2±0.4 mmol·L-1 in BIC (P<0.05). Concomitantly, pre-exercise pH values gradually decreased in PL (from 7.41±0.00 to 7.39±0.01) and increased in BIC (from 7.41±0.01 to 7.47±0.01; P<0.05). Mean power output of the four bouts was higher in BIC (428±20 W) than in PL (420±20 W; P<0.05). The ergogenic effect on repeated all-out exercise occurred in the absence of gastrointestinal distress.


Asunto(s)
Rendimiento Atlético/fisiología , Sustancias para Mejorar el Rendimiento/administración & dosificación , Bicarbonato de Sodio/administración & dosificación , Estudios Cruzados , Método Doble Ciego , Esquema de Medicación , Prueba de Esfuerzo , Enfermedades Gastrointestinales/inducido químicamente , Humanos , Concentración de Iones de Hidrógeno , Ácido Láctico/sangre , Masculino , Sustancias para Mejorar el Rendimiento/efectos adversos , Sustancias para Mejorar el Rendimiento/sangre , Bicarbonato de Sodio/efectos adversos , Bicarbonato de Sodio/sangre , Adulto Joven
12.
Drug Test Anal ; 11(9): 1290-1301, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31232530

RESUMEN

Recombinant human erythropoietin (rHuEPO) is used as doping a substance. Anti-doping efforts include urine and blood testing and monitoring the athlete biological passport (ABP). As data on the performance of these methods are incomplete, this study aimed to evaluate the performance of two common urine assays and the ABP. In a randomized, double-blinded, placebo-controlled trial, 48 trained cyclists received a mean dose of 6000 IU rHuEPO (epoetin ß) or placebo by weekly injection for eight weeks. Seven timed urine and blood samples were collected per subject. Urine samples were analyzed by sarcosyl-PAGE and isoelectric focusing methods in the accredited DoCoLab in Ghent. A selection of samples, including any with false presumptive findings, underwent a second sarcosyl-PAGE confirmation analysis. Hematological parameters were used to construct a module similar to the ABP and analyzed by two evaluators from an Athlete Passport Management Unit. Sensitivity of the sarcosyl-PAGE and isoelectric focusing assays for the detection of erythropoietin abuse were 63.8% and 58.6%, respectively, with a false presumptive finding rate of 4.3% and 6%. None of the false presumptive findings tested positive in the confirmation analysis. Sensitivity was highest between 2 and 6 days after dosing, and dropped rapidly outside this window. Sensitivity of the ABP was 91.3%. Specificity of the urine assays was high; however, the detection window of rHuEPO was narrow, leading to questionable sensitivity. The ABP, integrating longitudinal data, is more sensitive, but there are still subjects that evade detection. Combining these methods might improve performance, but will not resolve all observed shortcomings.


Asunto(s)
Electroforesis en Gel de Poliacrilamida/métodos , Eritropoyetina/sangre , Eritropoyetina/orina , Focalización Isoeléctrica/métodos , Adulto , Atletas , Ciclismo , Doping en los Deportes , Método Doble Ciego , Eritropoyetina/administración & dosificación , Humanos , Masculino , Persona de Mediana Edad , Sustancias para Mejorar el Rendimiento/administración & dosificación , Sustancias para Mejorar el Rendimiento/sangre , Sustancias para Mejorar el Rendimiento/orina , Efecto Placebo , Proteínas Recombinantes/administración & dosificación , Proteínas Recombinantes/sangre , Proteínas Recombinantes/orina , Detección de Abuso de Sustancias/métodos , Adulto Joven
13.
J Clin Endocrinol Metab ; 104(7): 2490-2500, 2019 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-30753550

RESUMEN

CONTEXT: The lifetime prevalence of anabolic androgenic steroid (AAS) use is estimated at 1% to 5% worldwide. AAS use occurs primarily male elite athletes and men who want a muscular appearance. The evidence for effective, safe management of AAS cessation and withdrawal is weak. DESIGN: Key studies were extracted from PubMed (1990-2018) and Google Scholar with reference searches from relevant retrieved articles. RESULTS: The proven adverse effects of AASs include suppression of the gonadal axis and infertility, hirsutism and defeminization in women, and erythrocytosis. Alkylated AASs that are taken orally may cause hepatopathy. There is an association between high-dosage AAS use and increased risk of cardiovascular disease. Clues for AAS use include very low serum high-density cholesterol and sex hormone-binding globulin concentrations and unexplained erythrocytosis. For elite athletes, the biological passport (monitoring of blood or urinary androgen and androgen precursor concentrations after determining the athlete's baseline) is useful for detecting AAS use. For nonelite athletes, the best method to confirm AAS use is to inquire in a nonjudgmental manner. Cessation of chronic AAS use is associated with a withdrawal syndrome of anxiety and depression. CONCLUSIONS: Men who use AASs <1 year typically recover normal hypothalamic-pituitary-testicular axis function within 1 year after cessation. Men who have infertility due to high-dosage AAS use ≥1 year might benefit from short-term treatment with clomiphene or human chorionic gonadotropin.


Asunto(s)
Anabolizantes/efectos adversos , Andrógenos/efectos adversos , Sustancias para Mejorar el Rendimiento/efectos adversos , Detección de Abuso de Sustancias/métodos , Trastornos Relacionados con Sustancias/diagnóstico , Anabolizantes/administración & dosificación , Anabolizantes/sangre , Anabolizantes/orina , Andrógenos/administración & dosificación , Andrógenos/sangre , Andrógenos/orina , Atletas/legislación & jurisprudencia , Doping en los Deportes/legislación & jurisprudencia , Doping en los Deportes/prevención & control , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Masculino , Sustancias para Mejorar el Rendimiento/administración & dosificación , Sustancias para Mejorar el Rendimiento/sangre , Sustancias para Mejorar el Rendimiento/orina , Prevalencia , Factores Sexuales , Trastornos Relacionados con Sustancias/epidemiología , Trastornos Relacionados con Sustancias/etiología , Trastornos Relacionados con Sustancias/terapia
14.
Drug Test Anal ; 11(6): 772-781, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30636357

RESUMEN

Erythropoiesis-stimulating agents (ESAs) have been used in horses for doping purposes to increase the performance of these animals in endurance sports. Currently, enzyme-linked immunosorbent assay (ELISA) and mass spectrometry methods are used to detect ESA abuse in equines. However, the sarcosyl polyacrylamide gel-electrophoresis (SAR-PAGE) technique could also be used, since its application in human doping control is well established and has proven to be more sensitive. In this work, the SAR-PAGE method was used to detect recombinant human erythropoietin (rHuEPO), novel erythropoiesis stimulating protein (NESP), continuous erythropoietin receptor activator (CERA), and fusion protein of erythropoietin with human immunoglobulin heavy chain Fc region (EPO-Fc) in horse blood and urine. The purification technique for human blood using MAIIA kits worked well for horse samples. The major challenge was horse urine immunopurification, which proved difficult due to filter clogging, but heating and cooling of the horse urine followed by filtration in 30-kDa molecular weight cut-off filters solved this problem. The limits of detection (LODs) of 1.3, 1.6, 6.6, and 13.3 pg/mL for rHuEPO, NESP, CERA, and EPO-Fc, respectively, obtained in spiked urine and 40, 100, 80, and 400 pg/mL for rHuEPO, NESP, CERA, and EPO-Fc, respectively, acquired in spiked blood are lower than the LODs reported in the literature using liquid chromatography-mass spectrometry (LC-MS) methods. In addition, the presence of ESAs was detected up to 9 days after the administration of microdoses of Hemax (rHuEPO), NESP, and CERA in horse blood and urine. SAR-PAGE may be implemented in the routine analysis of horse doping control laboratories for screening and confirmation of ESA abuse, mainly due to its high sensitivity for both matrices compared to published mass spectrometric methods.


Asunto(s)
Electroforesis en Gel de Poliacrilamida/métodos , Eritropoyetina/sangre , Eritropoyetina/orina , Caballos/sangre , Caballos/orina , Animales , Detergentes/química , Doping en los Deportes , Masculino , Sustancias para Mejorar el Rendimiento/sangre , Sustancias para Mejorar el Rendimiento/orina , Sarcosina/análogos & derivados , Sarcosina/química , Detección de Abuso de Sustancias/métodos
15.
Med Sci Sports Exerc ; 51(6): 1195-1202, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30629046

RESUMEN

PURPOSE: This study aimed to determine whether 1) consumption of caffeine improves endurance cycling performance in women and 2) sex differences exist in the magnitude of the ergogenic and plasma responses to caffeine supplementation. METHODS: Twenty-seven (11 women and 16 men) endurance-trained cyclists and triathletes participated in this randomized, double-blind, placebo-controlled, crossover study. Participants completed an incremental exercise test to exhaustion, two familiarization trials, and two performance trials. Ninety minutes before the performance trials, participants ingested opaque capsules containing either 3 mg·kg body mass of anhydrous caffeine or a placebo. They then completed a set amount of work (75% of peak sustainable power output) in the fastest possible time. Plasma was sampled at baseline, preexercise, and postexercise for caffeine. Strict standardization and verification of diet, hydration, training volume and intensity, and contraceptive hormone phase (for women) were implemented. RESULTS: Performance time was significantly improved after caffeine administration in women (placebo: 3863 ± 419 s, caffeine: 3757 ± 312 s; P = 0.03) and men (placebo: 3903 ± 341 s, caffeine: 3734 ± 287 s; P < 0.001). The magnitude of performance improvement was similar for women (mean = 4.3%, 95% CI = 0.4%-8.2%) and men (4.6%, 2.3%-6.8%). Plasma caffeine concentrations were similar between sexes before exercise, but significantly greater in women after exercise (P < 0.001). CONCLUSIONS: Ingestion of 3 mg·kg body mass of caffeine enhanced endurance exercise performance in women. The magnitude of the performance enhancement observed in women was similar to that of men, despite significantly greater plasma caffeine concentrations after exercise in women. These results suggest that the current recommendations for caffeine intake (i.e., 3-6 mg·kg caffeine before exercise to enhance endurance performance), which are derived almost exclusively from studies on men, may also be applicable to women.


Asunto(s)
Ciclismo/fisiología , Cafeína/administración & dosificación , Estimulantes del Sistema Nervioso Central/administración & dosificación , Sustancias para Mejorar el Rendimiento/administración & dosificación , Resistencia Física/fisiología , Adulto , Índice de Masa Corporal , Cafeína/sangre , Estimulantes del Sistema Nervioso Central/sangre , Estudios Cruzados , Método Doble Ciego , Femenino , Frecuencia Cardíaca/fisiología , Humanos , Masculino , Sustancias para Mejorar el Rendimiento/sangre , Factores Sexuales , Adulto Joven
16.
J Sports Sci ; 37(13): 1464-1471, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30668281

RESUMEN

This study investigated the effects of two separate doses of sodium bicarbonate (NaHCO3) on 4 km time trial (TT) cycling performance and post-exercise acid base balance recovery in hypoxia. Fourteen club-level cyclists completed four cycling TT's, followed by a 40 min passive recovery in normobaric hypoxic conditions (FiO2 = 14.5%) following one of either: two doses of NaHCO3 (0.2 g.kg-1 BM; SBC2, or 0.3 g.kg-1 BM; SBC3), a taste-matched placebo (0.07 g.kg-1 BM sodium chloride; PLA), or a control trial in a double-blind, randomized, repeated-measures and crossover design study. Compared to PLA, TT performance was improved following SBC2 (p = 0.04, g = 0.16, very likely beneficial), but was improved to a greater extent following SBC3 (p = 0.01, g = 0.24, very likely beneficial). Furthermore, a likely benefit of ingesting SBC3 over SBC2 was observed (p = 0.13, g = 0.10), although there was a large inter-individual variation. Both SBC treatments achieved full recovery within 40 min, which was not observed in either PLA or CON following the TT. In conclusion, NaHCO3 improves 4 km TT performance and acid base balance recovery in acute moderate hypoxic conditions, however the optimal dose warrants an individual approach.


Asunto(s)
Equilibrio Ácido-Base/efectos de los fármacos , Rendimiento Atlético/fisiología , Ciclismo/fisiología , Sustancias para Mejorar el Rendimiento/administración & dosificación , Bicarbonato de Sodio/administración & dosificación , Adolescente , Adulto , Estudios Cruzados , Método Doble Ciego , Femenino , Enfermedades Gastrointestinales/inducido químicamente , Frecuencia Cardíaca , Humanos , Concentración de Iones de Hidrógeno , Hipoxia , Masculino , Oxígeno/sangre , Percepción , Sustancias para Mejorar el Rendimiento/efectos adversos , Sustancias para Mejorar el Rendimiento/sangre , Esfuerzo Físico , Bicarbonato de Sodio/efectos adversos , Bicarbonato de Sodio/sangre , Adulto Joven
17.
Int J Sports Physiol Perform ; 14(4): 426-431, 2019 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-30204516

RESUMEN

PURPOSE: To investigate the influence of torque factor and sprint duration on the effects of caffeine on sprint cycling performance. METHODS: Using a counterbalanced, randomized, double-blind, placebo-controlled design, 13 men completed 9 trials. In trial 1, participants completed a series of 6-s sprints at increasing torque factors to determine the torque factor, for each individual, that elicited the highest (Toptimal) peak power output (PPO). The remaining trials involved all combinations of torque factor (0.8 N·m-1·kg-1 vs Toptimal), sprint duration (10 s vs 30 s), and supplementation (caffeine [5 mg·kg-1] vs placebo). RESULTS: There was a significant effect of torque factor on PPO, with higher values at Toptimal (mean difference 168 W; 95% likely range 142-195 W). There was also a significant effect of sprint duration on PPO, with higher values in 10-s sprints (mean difference 52 W; 95% likely range 18-86 W). However, there was no effect of supplementation on PPO (P = .056). Nevertheless, there was a significant torque factor × sprint duration × supplement interaction (P = .036), with post hoc tests revealing that caffeine produced a higher PPO (mean difference 76 W; 95% likely range 19-133 W) when the sprint duration was 10 s and the torque factor was Toptimal. CONCLUSION: The results of this study show that when torque factor and sprint duration are optimized, to allow participants to express their highest PPO, there is a clear effect of caffeine on sprinting performance.


Asunto(s)
Rendimiento Atlético/fisiología , Ciclismo/fisiología , Cafeína/farmacología , Sustancias para Mejorar el Rendimiento/farmacología , Cafeína/administración & dosificación , Cafeína/sangre , Suplementos Dietéticos , Método Doble Ciego , Prueba de Esfuerzo , Humanos , Rodilla/fisiología , Masculino , Músculo Esquelético/fisiología , Sustancias para Mejorar el Rendimiento/sangre , Factores de Tiempo , Torque , Adulto Joven
18.
Drug Test Anal ; 10(11-12): 1714-1721, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30285318

RESUMEN

Therapeutic proteins are a continuously growing class of pharmaceuticals and comprise several drug candidates with potential performance-enhancing properties. In particular, activin receptor competitors, such as the ActRII-Fc fusion proteins Sotatercept (ActRIIA-Fc) and Luspatercept (modified ActRIIB-Fc), have the potential for being misused as doping agents in sports as they were found to inhibit negative regulators of late-stage erythropoiesis. Within this study, ammonium sulfate precipitation, immunoaffinity purification, tryptic digestion, and liquid chromatography-tandem mass spectrometry (LC-MS/MS) were employed to develop an assay for the combined detection of Sotatercept and Luspatercept in doping control serum samples. The assay was optimized, comprehensively characterized, and found to be fit-for-purpose for application to sports drug testing. It complements existing tests for ActRII-Fc fusion proteins and expands the range of available detection methods for novel protein therapeutics.


Asunto(s)
Activinas/sangre , Cromatografía Líquida de Alta Presión/métodos , Fragmentos Fc de Inmunoglobulinas/sangre , Inmunoprecipitación/métodos , Proteínas Recombinantes de Fusión/sangre , Espectrometría de Masas en Tándem/métodos , Receptores de Activinas Tipo II , Activinas/análisis , Activinas/aislamiento & purificación , Precipitación Química , Humanos , Fragmentos Fc de Inmunoglobulinas/análisis , Fragmentos Fc de Inmunoglobulinas/aislamiento & purificación , Límite de Detección , Sustancias para Mejorar el Rendimiento/sangre , Proteolisis , Proteínas Recombinantes de Fusión/análisis , Proteínas Recombinantes de Fusión/aislamiento & purificación , Detección de Abuso de Sustancias/métodos , Tripsina/química
19.
Am J Physiol Regul Integr Comp Physiol ; 315(3): R453-R460, 2018 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-29693429

RESUMEN

Previous studies showed a higher O2 cost of exercise, and therefore, a reduced exercise tolerance in patients with obesity during constant work rate (CWR) exercise compared with healthy subjects. Among the ergogenic effects of dietary nitrate ([Formula: see text]) supplementation in sedentary healthy subjects, a reduced O2 cost and enhanced exercise tolerance have often been demonstrated. The aim of this study was to evaluate the effects of beetroot juice (BR) supplementation, rich in [Formula: see text], on physiological variables associated with exercise tolerance in adolescents with obesity. In a double-blind, randomized crossover study, 10 adolescents with obesity (8 girls, 2 boys; age = 16 ± 1 yr; body mass index = 35.2 ± 5.0 kg/m2) were tested after 6 days of supplementation with BR (5 mmol [Formula: see text] per day) or placebo (PLA). Following each supplementation period, patients carried out two repetitions of 6-min moderate-intensity CWR exercise and one severe-intensity CWR exercise until exhaustion. Plasma [Formula: see text] concentration was significantly higher in BR versus PLA (108 ± 37 vs. 15 ± 5 µM, P < 0.0001). The O2 cost of moderate-intensity exercise was not different in BR versus PLA (13.3 ± 1.7 vs. 12.9 ± 1.1 ml·min-1·W-1, P = 0.517). During severe-intensity exercise, signs of a reduced amplitude of the O2 uptake slow component were observed in BR, in association with a significantly longer time to exhaustion (561 ± 198 s in BR vs. 457 ± 101 s in PLA, P = 0.0143). In obese adolescents, short-term dietary [Formula: see text] supplementation is effective in improving exercise tolerance during severe-intensity exercise. This may prove to be useful in counteracting early fatigue and reduced physical activity in this at-risk population.


Asunto(s)
Beta vulgaris , Terapia por Ejercicio/métodos , Tolerancia al Ejercicio/efectos de los fármacos , Jugos de Frutas y Vegetales , Nitratos/administración & dosificación , Obesidad Infantil/terapia , Sustancias para Mejorar el Rendimiento/administración & dosificación , Raíces de Plantas , Adolescente , Beta vulgaris/efectos adversos , Índice de Masa Corporal , Estudios Cruzados , Método Doble Ciego , Prueba de Esfuerzo , Terapia por Ejercicio/efectos adversos , Jugos de Frutas y Vegetales/efectos adversos , Humanos , Italia , Masculino , Fatiga Muscular/efectos de los fármacos , Nitratos/efectos adversos , Nitratos/sangre , Obesidad Infantil/sangre , Obesidad Infantil/diagnóstico , Obesidad Infantil/fisiopatología , Sustancias para Mejorar el Rendimiento/efectos adversos , Sustancias para Mejorar el Rendimiento/sangre , Raíces de Plantas/efectos adversos , Factores de Tiempo , Resultado del Tratamiento
20.
Drug Test Anal ; 10(5): 802-806, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29524351

RESUMEN

The Athlete Biological Passport (ABP) refers to the collection of data related to an individual athlete. The ABP contains the Haematological Module and the Steroidal Module, which are used for the longitudinal monitoring of variables in blood and urine, respectively. Based on changes in these variables, a statistical model detects outliers which indicate doping use and guide further targeted testing of the athlete. Presently, athletes can access their data of the Haematological Module in the Anti-Doping Administration and Management System (ADAMS). However, granting athletes access to this data has been a matter of debate within the anti-doping community. This article investigates whether an athlete has a right to access the contents of their ABP profile. We approached this discussion by comparing the nature of ABP data with that of forensic and medical data and touched on important concerns with ABP data disclosure to athletes such as potentially allowing for the development of alternative doping techniques to circumvent detection; and making athletes vulnerable to pressure by the media to publicly release their data. Furthermore, given that ABP data may contain medically relevant information that can be used to diagnose disease, athletes may over-interpret its medical significance and wrongly see it as a free health check. We argue that safeguarding the integrity of the ABP system must be seen as the most essential element and thus a departure from immediate data disclosure is necessary. Two different strategies for delayed data disclosure are proposed which diminish the chances of ABP data being misused to refine doping techniques.


Asunto(s)
Atletas , Doping en los Deportes , Detección de Abuso de Sustancias , Acceso a la Información , Doping en los Deportes/ética , Humanos , Sustancias para Mejorar el Rendimiento/sangre , Sustancias para Mejorar el Rendimiento/orina , Esteroides/sangre , Esteroides/orina , Detección de Abuso de Sustancias/ética , Detección de Abuso de Sustancias/métodos
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