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We investigated the bioavailability of the calcium salt (HMB-Ca) and the free acid (HMB-FA) forms of ß-hydroxy-ß-methylbutyrate (HMB). Sixteen young individuals received the following treatments on three different occasions in a counterbalanced crossover fashion: (1) HMB-FA in clear capsules; (2) HMB-Ca in gelatine capsules; (3) HMB-Ca dissolved in water. All treatments provided 1 g of HMB. Blood samples were taken before and on multiple time points following ingestion. The following parameters were calculated: peak plasma (Cmax), time to peak (Tmax), slope of HMB appearance in blood, area under the curve (AUC), half-life time (t1/2) and relative bioavailability (HMB-Ca in water set as reference). All treatments led to rapid and large increases in plasma HMB. HMB-Ca in capsules and in water showed similar plasma HMB values across time (p = 0.438). HMB-FA resulted in lower concentrations vs. the other treatments (both p < 0.001). AUC (HMB-Ca in capsules: 50,078 ± 10,507; HMB-Ca in water: 47,871 ± 10,783; HMB-FA: 29,130 ± 12,946 µmol L-1 × 720 min), Cmax (HMB-Ca in capsules: 229.2 ± 65.9; HMB-Ca in water: 249.7 ± 49.7; HMB-FA: 139.1 ± 67.2 µmol L-1) and relative bioavailability (HMB-Ca in capsules: 104.8 ± 14.9%; HMB-FA: 61.5 ± 17.0%) were lower in HMB-FA vs. HMB-Ca (all p < 0.001). HMB-Ca in water resulted in the fastest Tmax (43 ± 22 min) compared to HMB-Ca in capsules (79 ± 40 min) and HMB-FA (78 ± 21 min) (all p < 0.05), while t1/2 was similar between treatments. To conclude, HMB-Ca exhibited superior bioavailability compared to HMB-FA, with HMB-Ca in water showing faster absorption. Elimination kinetics were similar across all forms, suggesting that the pharmaceutical form of HMB affects the absorption rates, but not its distribution or elimination.

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Adenosine triphosphate (ATP) is an energy and signaling molecule. It is synthesized endogenously and can be taken as an oral supplement. This review aimed to identify the effects of oral ATP supplementation on anaerobic exercise in healthy resistance-trained adults. A systematic review and meta-analysis were performed based on the Preferred Reporting Items of Systematic Reviews and Meta-Analysis (PRISMA) criteria. The inclusion criteria were articles published from 2000 to 2022, with anaerobic variables (maximal strength, maximum repetitions, and maximum anaerobic power) measurable in healthy adults with experience in resistance training, only randomized placebo-controlled clinical trials (RCTs), and with the acute (a single dose 30 min to 24 h before the tests) and/or chronic (>1 day) oral supplementation of ATP. A total of five RCTs with 121 adult men were included. The oral ATP supplementation achieved significantly greater gains in maximal strength compared with the placebo (PL) (MD = 8.13 kg, 95%CI [3.36-12.90], p < 0.001). Still, no differences were observed in the maximum number of repetitions or the maximum anaerobic power. Furthermore, 400 mg of ATP showed improvement in anaerobic exercise regardless of the duration of the supplementation protocol. In conclusion, supplementation with 400 mg of ATP doses can improve maximal muscle strength in resistance-trained men.

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Resumo O presente ensaio crítico-reflexivo busca discutir a medicalização da performance a partir de reflexões sobre a flexibilização no mundo do trabalho e o fenômeno do empreendedorismo de si. Em um contexto de financeirização da economia, reestruturação produtiva e fragilização do Estado como esfera garantidora dos direitos sociais, impera a precarização e a informalidade, onde a flexibilização do trabalho ocorre em consonância com estratégias político-ideológicas de inspiração neoliberal. Emergem então, modos de individualização atrelados à construção de um trabalhador disposto a desenvolver variadas habilidades, que passa a ser um potencial empreendimento e ter como princípio a mesma dinâmica mercadológica deste. O empreendedor de si mesmo precisa investir em si para manter-se valorizado e em boas condições de funcionamento, de modo a evitar a sua descapitalização. Para dar condições ao sujeito de sustentar a imagem de sucesso e de autor de sua própria história, a utilização de medicamentos, estimulantes e polivitamínicos, tem sido usada como estratégia em busca de alta performance. Problematizar os "empreendedores de si", as novas formas de subjetivação e o sofrimento advindo destas, bem como a maquinaria que os produzem é necessário, e se constitui um desafio para a saúde coletiva.

Abstract This critical-reflective essay seeks to discuss the medicalization of performance based on reflections on flexibility in the world of work and the phenomenon of self-entrepreneurship. In a context of economy financialization, productive restructuring and State's weakening as guarantor of social rights, precarization and informality are increasingly prevailing, where the promotion of labour flexibilization occurs in line with political-ideological strategies of neoliberal inspiration. There emerge ways of individualization tied to the construction of a multifunctional worker, available to develop multiple abilities, which becomes a potential enterprise and has as a principle the same market dynamics as this enterprise. The entrepreneur of the self needs to invest in itself to keep being valuable and having great functioning conditions, in order to avoid, to the fullest, its own decapitalization. Therefore, in order to enable conditions to sustain the image of success and of author of its own story, the usage of medicines, stimulants and multivitamins has been used as a strategy in search of high performance. To reflect on "the entrepreneur of the self", the new ways of subjectivity and the suffering derived from those, as well as the apparatus that produces them, is necessary and consists in a challenge for community health.

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As percepções e o uso de metilfenidato entre universitários foram investigados em estudo descritivo realizado em duas etapas. A primeira, quantitativa, foi realizada por meio do preenchimento de um questionário semiestruturado on-line. Para a segunda etapa, qualitativa, foi realizado um grupo focal. Dos 337 participantes da primeira etapa, 14,5% relataram usar o metilfenidato. Entre os usuários, a prevalência de uso sem prescrição foi maior para o sexo masculino (65,3%), após ingresso na faculdade (57,1%), e 61,2% relataram eventos adversos. O principal motivo de uso foi o doping intelectual (65,3%). Já na etapa qualitativa, além de reforçar os achados anteriores, foram identificados tópicos temáticos como a pressão externa exercida por familiares, sociedade e a rotina universitária. Esses achados apontam para a necessidade de medidas de apoio e orientação aos universitários e de reformulação do processo ensino-aprendizagem.(AU)

This descriptive study investigated the use and perceptions of methylphenidate among university students. The study was conducted in two stages. In the first stage (quantitative), the students completed an online semi-structured questionnaire. The second stage (qualitative) consisted of focus group discussions. Of the 337 participants in the first stage, 14.5% reported using methylphenidate. The prevalence of methylphenidate use without a prescription was greater among men (65.3%) and after starting university (57.1%); 61.2% of the students reported adverse events. The main reason for using the drug was intellectual doping (65.3%). In the qualitative stage, which reinforced the findings of the quantitative stage, we identified themes such as external pressure from family, society and university routine. The findings underline the need to provide student support and advice and reformulate the teaching and learning process.(AU)

Se investigaron las percepciones y el uso del metilfenidato entre universitarios, en un estudio descriptivo realizado en dos etapas. La primera, cuantitativa, se realizó por medio del llenado de un cuestionario semiestructurado online. Para la segunda etapa, cualitativa, se realizó un grupo focal. De los 337 participantes de la primera etapa, el 14,5% relató que usaba metilfenidato. Entre los usuarios, la prevalencia de uso sin prescripción fue mayor para el sexo masculino (65,3%), después del ingreso en la facultad (57,1%) y el 61,2% relataron eventos adversos. El principal motivo de uso fue el dopping intelectual (65,3%). En la etapa cualitativa, además de reforzar los hallazgos anteriores, se identificaron tópicos temáticos tales como la presión externa ejercida por los familiares, la sociedad y la rutina universitaria. Esos hallazgos señalan la necesidad de medidas de apoyo y orientación a los universitarios y de reformulación del proceso enseñanza-aprendizaje.(AU)

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Abstract Introduction We draw on activity theory of concepts to examine 'meaning of occupation' and 'substance use' beyond preconceived notions of inherent positive or negative experiences. Objective To explore nuanced meanings of substance use and associated occupations. Method An online survey and semi-structured interviews were used to collect data from professionals about prevalence of substance use, substance effects, and personal experiences. In analyzing the interview data, we attended to substance use as a discrete occupation in itself, substance use co-occurring with other occupations, and substance use altering the performance, participation, and experience of occupations. Results Three broad themes related to meaning: i) complex meanings attributed to substance use, ii) meanings of substance use as shifting and variable, and iii) meanings of substance use in the context of other occupations. Substance use enhances occupations, transforms meaning of occupations, and mitigates less desired aspects of occupations. Work, construed as positively meaningful and valued in occupational therapy literature, was a source of stress, unhappiness, and worry; substance use facilitated relaxation and pleasure. Conclusion This study furthers occupational therapy knowledge with respect to implications for conceptualization that extend beyond dualist framings and implications for occupational therapy education, practice, and policy.

Resumo Introdução Foi utilizada a teoria da atividade de conceitos para examinar o "significado da ocupação" e o "uso de substâncias" para além das noções preconcebidas de experiências inerentes positivas ou negativas. Objetivo Explorar nuances do significado do uso de substâncias e as ocupações associadas. Método Uma pesquisa online e entrevistas semiestruturadas foram usadas para coletar dados de profissionais sobre a prevalência do uso de substâncias, efeitos de substâncias e experiências pessoais. Ao analisar os dados da entrevista, observamos que o uso de substâncias é uma ocupação discreta em si, ocorrendo com outras ocupações e o uso de substâncias altera o desempenho, a participação e a experiência das ocupações. Resultados Três grandes temas relacionados ao significado: i) significados complexos atribuídos ao uso de substâncias, ii) significados do uso de substâncias como mutante e variável, e iii) significados do uso de substâncias no contexto de outras ocupações. O uso de substâncias enlaça-se às ocupações, transforma os seus significados e mitiga aspectos menos desejados das ocupações. O trabalho, considerado positivamente significativo e valorizado na literatura da terapia ocupacional, era uma fonte de estresse, infelicidade e preocupação; o uso de substâncias facilitou o relaxamento e o prazer. Conclusão Este estudo aprofunda o conhecimento da terapia ocupacional com implicações para ampliar a conceptualização para além da fragmentação dualista e oferta implicações para a formação em terapia ocupacional, para a prática e a política.

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Abstract Aim: To verify the acute effect of sodium bicarbonate (NaHCO3) supplementation on performance during CrossFit® workout. Methods: Nine experienced males (30.8 ± 3.5 years; 84.4 ± 9.5 kg; 177.5 ± 4.03 cm; 2.2 ± 1.0 years) in CrossFit® participated in this study. They were allocated to two conditions: a) supplementation with 0.3 g.kg-1 of body weight of NaHCO3 and b) supplementation with 0.045 g.kg-1 of body weight of sodium chloride (NaCl). Blood lactate was analyzed at two different moments: before (lac-pre) and after the training protocol (lac-post). The heart rate (HR) and the rating of perceived exertion (RPE) were also collected every two minutes during the execution of the training protocol, and the RPE was also collected after it was finished. At the end of the training protocol, a questionnaire to measure gastrointestinal side effects (GSE) was answered by the participants. Repetitions performed in the training protocol was computed to evaluate the performance during the workout. Results: The results showed that there were no differences found when comparing the conditions for all parameters. HR and RPE were different in the first few minutes (< 4-6 minutes) when compared to the final minutes (> 14 minutes) of the workout. The area under the curve of HR and RPE was significantly lower in the NaHCO3 condition. Conclusion: Acute NaHCO3 supplementation did not improve performance during workout 'Cindy' in experienced men. Supplementation also did not alter hemodynamic and perceptual parameters, nor did it cause any GSE. However, responses as a function of time were reduced with NaHCO3 supplementation.

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ABSTRACT The purpose of this review was to examine in the current literature the advances made in terms of the effects of caffeine supplementation on maximum strength and its associated mechanisms since the publication of two important papers in 2010. Searches were carried out in the PubMed, Medline, Scielo and Web of Science databases for articles published after 2010. Sixteen studies were included based on inclusion and exclusion criteria. Five studies did not report changes in maximal voluntary strength (31.3%). Four of them used isometric muscle contractions, although this may not be a key factor because five other studies also used isometric contractions and reported ergogenic effects. Furthermore, these four studies evaluated small muscle groups and volunteers were not accustomed to consuming caffeine. Caffeine produced ergogenic effects in eleven of the sixteen studies analyzed (68.8%). None of the doses were clearly related to ergogenic effects; however, a dose of at least 3 mg/kg of caffeine is probably necessary. Caffeine ergogenicity was affected by various factors. There was a lack of standardized protocols and controls for intervening factors (e.g., circadian cycles and nutritional states), which could affect results. An ideal caffeine supplementation protocol that is useful for future research, athletes, and physical activity practitioners, has yet to be defined. A small advance made since 2010 involved a possible lack of gender difference; it would appear that caffeine supplementation affects men and women equally. Level of Evidence I; Systematic Review of Level I Studies.

RESUMO O objetivo desta revisão foi examinar na literatura atual os avanços feitos com relação aos efeitos da suplementação de cafeína sobre a força máxima e seus mecanismos associados a partir de 2010, ano em foram publicados dois importantes artigos. As buscas foram realizadas nas bases de dados PubMed, Medline, Scielo e Web of Science procurando-se artigos publicados após 2010. Dezesseis estudos foram incluídos com base nos critérios de inclusão e exclusão. Cinco estudos não relataram alterações da força voluntária máxima (31,3%). Quatro deles usaram contrações musculares isométricas, embora isso possa não ser um fator chave, porque outros cinco estudos também usaram contrações isométricas e relataram efeitos ergogênicos. Além disso, esses quatro estudos avaliaram pequenos grupos musculares e os voluntários não eram habituados à cafeína. A cafeína produziu efeitos ergogênicos em 11 dos 16 estudos analisados (68,8%). Nenhuma dose foi claramente relacionada com efeitos ergogênicos; contudo, há indícios da necessidade de uma dose de pelo menos 3 mg/kg de cafeína. A ergogenicidade da cafeína foi afetada por vários fatores. Havia uma falta de protocolos padronizados e controle de fatores intervenientes (por exemplo, ciclo circadiano e estado nutricional) que poderiam afetar os resultados. Ainda é preciso definir um protocolo ideal de suplementação de cafeína que seja útil para futuras pesquisas, atletas e praticantes de atividade física. Um pequeno avanço feito desde 2010 envolveu a possível falta de diferença de gênero - parece que a suplementação de cafeína afeta homens e mulheres igualmente. Nível de Evidência I; Revisão Sistemática de Estudos de Nível I.

RESUMEN El objetivo de esta revisión fue examinar en la literatura actuallos avances hechos con respecto a los efectos del suplemento de cafeína sobre la fuerza máxima y sus mecanismos asociados desde 2010, año en que se publicaron dos artículos importantes. Las búsquedas se realizaron en las bases de datos PubMed, Medline, Scielo y Web of Science, por artículos publicados después de 2010. Se incluyeron 16 estudios basados en los criterios de inclusión y exclusión. Cinco estudios no reportaron cambios de la fuerza voluntaria máxima (31,3%). Cuatro de ellos usaron contracciones musculares isométricas, aunque esto puede no ser un factor clave, porque otros cinco estudios también utilizaron contracciones isométricas y reportaron efectos ergogénicos. Además, estos cuatro estudios evaluaron grupos musculares pequeños y los voluntarios no tenían el hábito de consumo de cafeína. La cafeína produjo efectos ergogénicos en 11 de los 16 estudios analizados (68,8%). Ninguna dosis fue claramente relacionada con efectos ergogénicos, sin embargo, hay indicios de la necesidad de una dosis de al menos 3 mg/kg de cafeína. La ergogenicidad de la cafeína se vio afectada por varios factores. Hubo una falta de protocolos y controles estandarizados de factores intervinientes (por ejemplo, ciclo circadiano y estado nutricional) que podrían afectar los resultados. Todavía es necesario definir un protocolo ideal de suplemento de cafeína que sea útil para futuras investigaciones, atletas y practicantes de actividad física. Un pequeño avance hecho desde 2010 involucró la posible falta de diferencia de género - parece que el suplemento de cafeína afecta a hombres y mujeres igualmente. Nivel de Evidencia I; Revisión sistemática de estudios de Nivel I.

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Caffeine containing energy drink (ED) is frequently used as ergogenic aid, but its effect on performance need more investigation. Thus, the aim of this study was to analyze the effects of acute ingestion of an ED on the physical performance of resistance-trained men subjected to successive tests in the same experimental protocol. Fifteen resistance-trained males (21.0 ± 0.3 yrs; 177.4 ± 1.8 cm; 79.6 ± 1.8 kg) ingested 2.5 mg caffeine per kg of body weight (619.5 ± 14.6 mL of ED) or a placebo in a double-blind randomized cross-over design. Physical performance was randomized for the maximum repetition tests (80% 1RM) in the bench press exercise and unilateral knee extension (dominant leg), maximal isometric hand-grip test in both hands, standing long jump and repeated sprint ability test. The paired Student-t test showed that ED intake increased performance compared to the placebo for the number of repetitions in the unilateral knee extension test of the dominant leg (11.5 ± 0.9 reps vs 9.5 ± 0.8 reps; P = 0.001) and bench press (10.2 ± 0.4 reps vs 8.1 ± 0.5 reps; P = 0.01); and also increased isometric strength in the hand-grip maximal test in the right (53.7 ± 1.5 kg vs. 47.7 ± 1.6 kg; P = 0.02) and left hand (52.9 ± 1.5 kg vs. 45.9 ± 1.3 kg; P = 0.02). In conclusion, acute ingestion of ED increased performance only in specific strength tests in resistance-trained men.

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The number of offensive actions and glycolytic energy in combat sports both increase with caffeine (CAF) ingestion. In addition, the effects of CAF on technical-tactical and time-motion analysis and physiological parameters in boxing are unknown. This study aimed to investigate the effects of CAF ingestion on physiological parameters and the notational analysis of boxing matches. Ten male boxers were recruited; the participants ingested 6 mg kg-1 BM of CAF or placebo (PLA) 30 min prior to the match in a crossover design. Heart rate (HR) and rate of perceived exertion (RPE) were collected before and after each of three 2 min rounds, interspersed by 1-min recovery; the matches were recorded for notational analysis. A two-way ANOVA for repeated measures was used for the physiological variables, and a three-way ANOVA with repeated measures was used for technical-tactical and time-motion variables. Statistical differences were found for HR and RPE between rounds (F(6, 54) = 131.3, p = .001; [Formula: see text] = 0.93 and F(2, 18) = 40.6, p = .001; [Formula: see text] = 0.81, respectively) but not between conditions (F(1, 9) = 0.46; p = .51; [Formula: see text] = 0.05 and F(1, 9) = 0.02, p = .89; [Formula: see text] = 0.002, respectively). The CAF condition induced a greater duration of interaction blocks (CAF = 6.5 ± 1.8 s; PLA = 4.4 ± 0.9 s; p = .01). Effort:pause ratio was 4.4 s:8.7 s (approx. 1:2) for PLA and 6.5 s:9.4 s (1:1.44) for CAF, which were significantly different (p < .05). In conclusion, 6 mg kg-1 BM of CAF prior to simulated boxing matches induces a greater duration of high-intensity actions, with no effects on internal load markers.

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BACKGROUND: Probiotics are live microorganisms that promote health benefits to the host. Evidence indicates that some probiotic strains play an immunomodulatory role and reduce the incidence of respiratory and gastrointestinal infections in athletes and in physical activity practitioners. For this reason, probiotic supplementation could indirectly improve exercise performance. However, recent studies have observed direct ergogenic effects of probiotics, but the mechanisms of action are poorly elucidated. OBJECTIVE: In this study, we aim to synthesize available knowledge on the effect of probiotics on physical exercise, identify the mechanisms of action by which probiotics could improve performance directly and indirectly, and verify whether probiotics have any ergogenic effect. METHODS: The study was performed in the PubMed database in February 2017, without limitation as to the publication period. The keyword combinations used were: 'Probiotics' and 'Sports' ( n = 17 articles), 'Probiotics' and 'Exercise' ( n = 26 articles) and 'Probiotics' and 'Athletes' ( n = 11 articles). RESULTS: Of the 16 studies evaluated, only six applied performance tests, of which only two demonstrated that probiotic supplementation increases performance, but one of them was performed with mice. CONCLUSIONS: According to the studies evaluated, probiotic supplementation does not present ergogenic effect, however, considering the small number of studies, this subject should be better investigated.

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Abstract The use of ergogenic substances (UES) is not restricted to achieving a better athletic performance, but also it is a behaviour for body changing through muscle development; however, little is known about the relationship between muscle dysmorphia (MD) and UES. Therefore, it was conducted a systematic review of those empirical papers that have studied this relationship over the last decade (2004-2014). First it is highlighted that of the 22 articles analysed, only 13 explicitly aimed this interest. Besides, although the documented data outlined some relevant aspects such as the existence of a high co-occurrence (60-90%) between MD and UES. In general, the evidence is still incipient and uncertain, mainly because of the large disparity between the methodologies of the studies, particularly in terms of indicators, parameters and measures utilised to assess UES within the context of MD.

Resumen El uso de sustancias ergogénicas (USE) no se restringe a la consecución de un mayor desempeño atlético, actualmente también es una conducta de cambio corporal, vía el desarrollo muscular; no obstante, poco se sabe de la relación entre dismorfia muscular (DM) y USE. Por tanto se realizó una revisión sistemática de los estudios empíricos que, durante la última década (2004-2014), la han examinado. De entrada, destaca el hecho de que, de los 22 artículos analizados, solo en 13 se explicita este interés. Además, aunque los datos documentados delinean algunas vertientes relevantes, como la existencia de una alta concomitancia (60-90%) de DM y USE, en general las evidencias son aún incipientes e inciertas, principalmente debido a la gran disparidad metodológica entre estudios y, particularmente, en cuanto a los indicadores, los parámetros y las medidas que, en el contexto de la DM, se han venido empleando para evaluar USE.

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The use of ergogenic substances (UES) is not restricted to achieving a better athletic performance, but also it is a behavior for body changing through muscle development; however, little is known about the relationship between muscle dysmorphia (MD) and UES. Therefore, it was conducted a systematic review of those empirical papers that have studied this relationship over the last decade (2004-2014). First it is highlighted that of the 22 articles analyzed, only 13 explicitly aimed this interest. Besides, although the documented data outlined some relevant aspects such as the existence of a high co-occurrence (60-90%) between MD and UES. In general, the evidence is still incipient and uncertain, mainly because of the large disparity between the methodologies of the studies, particularly in terms of indicators, parameters and measures utilized to assess UES within the context of MD.

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Tendo em vista as condições contemporâneas de alteração das capacidades humanas no cam-po esportivo, este texto tem como objetivo discutir os limites e contingências envolvidas na definição e regulação do doping no esporte de alto rendimento. Articulando discussões acerca das possibilidades de otimização do desempenho físico-desportivo e dos registros provenien-tes da Agência Mundial Antidoping, estabelece-se uma discussão sobre os limiares de doping e as dificuldades impostas por tais condições na condução de seus processos regulatórios. Considera-se que há a necessidade de um debate amplo e revisional das políticas de doping contemporâneas, assim como, uma atenção permanente aos processos de transformações das capacidades humanas no tocante aos esportes de alto rendimento.

Given the contemporary conditions of change in human capabilities in the sports field, this text aims to discuss the limits and contingencies involved in the definition and regulation of doping in elite sport. Articulating discussions about the optimization of physical and sports performance and records from the World Anti-Doping Agency, we established a discussion of doping thresholds and the difficulties posed by such conditions in the conduct of its regulatory processes. It is considered that there is a need for a broad and revisional debate of contempo-rary doping policies, as well as continued attention to the transformation processes of human capacities with regard to elite sport.

Teniendo en cuenta las condiciones contemporáneas de alteración de las capacidades humanas en el campo deportivo, este trabajo tiene como objetivo discutir los límites y las contingencias que forman parte de la definición y regulación del dopaje en el deporte de alto rendimiento. Articulando discusiones acerca de las posibilidades de optimización del rendimiento físico-deportivo y los registros de la Agencia Mundial Antidopaje, se establece una discusión sobre los umbrales del dopaje y de las dificultades planteadas por esas condiciones en la conducción de sus procesos de regulación. Se considera la necesidad de un debate amplio y revisional de las políticas contemporáneas de dopaje, así como la atención continuada a los procesos de transformación de las capacidades humanas en relación con el deporte de alto rendimiento.

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PURPOSE: Caffeine-containing energy drinks (EDs) are currently used as ergogenic aids to improve physical performance in a wide variety of sport disciplines. However, the outcomes of previous investigations on this topic are inconclusive due to methodological differences, especially, in the dosage of the active ingredients and the test used to assess performance. METHODS: We performed a systematic review and meta-analysis of published studies to evaluate the effects of acute ED intake on physical performance. The search for references was conducted in the databases PubMed, ISI Web of Knowledge and SPORTDiscus until December 2015. RESULTS: Thirty-four studies published between 1998 and 2015 were included in the analysis. Using a random-effects model, effect sizes (ES) were calculated as the standardized mean difference. Overall, ED ingestion improved physical performance in muscle strength and endurance (ES = 0.49; p < 0.001), endurance exercise tests (ES = 0.53; p < 0.001), jumping (ES = 0.29; p = 0.01) and sport-specific actions (ES = 0.51; p < 0.001), but not in sprinting (ES = 0.14; p = 0.06). The meta-regression demonstrated a significant association between taurine dosage (mg) and performance (slope = 0.0001; p = 0.04), but not between caffeine dosage (mg) and performance (slope = 0.0009; p = 0.21). CONCLUSION: ED ingestion improved performance in muscle strength and endurance, endurance exercise tests, jumping and sport-specific actions. However, the improvement in performance was associated with taurine dosage.

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ABSTRACT. The so-called cognitive enhancers have been widely and increasingly used by healthy individuals who seek improvements in cognitive performance despite having no pathologies. One drug used for this purpose is methylphenidate, a first-line drug for the treatment of attention deficit hyperactivity disorder (ADHD). Objective: The aim of the present study was to test the effect of acute administration of varying doses of methylphenidate (10 mg, 20 mg, 40 mg and placebo) on a wide range of cognitive functions in healthy young people. Methods: A total of 36 young university students and graduates participated in the study. The participants underwent tests of attention and of episodic, and working memory. Results: No differences in performance were observed on any of the tests. There was a dose-dependent (40 mg > placebo) effect on self-reported wellbeing. Conclusions: According to the recent literature, psychostimulant medications, such as methylphenidate, improve performance when cognitive processes are below an optimal level, which was not the case for the subjects of the present study. We suggest the impression that methylphenidate enhances cognitive performance in healthy young people, justifying its use, may be due to improvements in subjective wellbeing promoted by the drug.

RESUMO. Os chamados ampliadores cognitivos têm sido ampla e crescentemente utilizados por indivíduos saudáveis, que apesar de não apresentarem nenhum tipo de patologia, buscam por melhoras no desempenho cognitivo. Um fármaco utilizado para este fim é o metilfenidato, droga de primeira escolha para tratamento do transtorno de déficit de atenção e hiperatividade (TDAH). Objetivo: O presente estudo teve como objetivo verificar o efeito da administração aguda de diferentes doses de metilfenidato (10, 20 e 40 mg e placebo) sobre uma ampla gama de funções cognitivas em jovens saudáveis. Métodos: Participaram do estudo 36 jovens universitários ou graduados, tendo sido realizados testes de atenção, memória operacional, episódica. Resultados: Não foram observadas diferenças no desempenho dos sujeitos em nenhum dos testes. Houve efeito na auto-avaliação de bem estar, sendo este efeito dose dependente (40 mg > placebo). Conclusão: De acordo com a literatura recente, medicações psicoestimulantes, como o metilfenidato, produzem melhoras no desempenho quando os processos cognitivos estão abaixo de um nível ótimo, o que não era o caso dos sujeitos do presente estudo. Sugerimos que a impressão de que o metilfenidato melhora o desempenho cognitivo em pessoas jovens e saudáveis se deve ao seu efeito subjetivo de bem-estar.

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The so-called cognitive enhancers have been widely and increasingly used by healthy individuals who seek improvements in cognitive performance despite having no pathologies. One drug used for this purpose is methylphenidate, a first-line drug for the treatment of attention deficit hyperactivity disorder (ADHD). OBJECTIVE: The aim of the present study was to test the effect of acute administration of varying doses of methylphenidate (10 mg, 20 mg, 40 mg and placebo) on a wide range of cognitive functions in healthy young people. METHODS: A total of 36 young university students and graduates participated in the study. The participants underwent tests of attention and of episodic, and working memory. RESULTS: No differences in performance were observed on any of the tests. There was a dose-dependent (40 mg > placebo) effect on self-reported wellbeing. CONCLUSIONS: According to the recent literature, psychostimulant medications, such as methylphenidate, improve performance when cognitive processes are below an optimal level, which was not the case for the subjects of the present study. We suggest the impression that methylphenidate enhances cognitive performance in healthy young people, justifying its use, may be due to improvements in subjective wellbeing promoted by the drug.

Os chamados ampliadores cognitivos têm sido ampla e crescentemente utilizados por indivíduos saudáveis, que apesar de não apresentarem nenhum tipo de patologia, buscam por melhoras no desempenho cognitivo. Um fármaco utilizado para este fim é o metilfenidato, droga de primeira escolha para tratamento do transtorno de déficit de atenção e hiperatividade (TDAH). OBJETIVO: O presente estudo teve como objetivo verificar o efeito da administração aguda de diferentes doses de metilfenidato (10, 20 e 40 mg e placebo) sobre uma ampla gama de funções cognitivas em jovens saudáveis. MÉTODOS: Participaram do estudo 36 jovens universitários ou graduados, tendo sido realizados testes de atenção, memória operacional, episódica. RESULTADOS: Não foram observadas diferenças no desempenho dos sujeitos em nenhum dos testes. Houve efeito na auto-avaliação de bem estar, sendo este efeito dose dependente (40 mg > placebo). CONCLUSÃO: De acordo com a literatura recente, medicações psicoestimulantes, como o metilfenidato, produzem melhoras no desempenho quando os processos cognitivos estão abaixo de um nível ótimo, o que não era o caso dos sujeitos do presente estudo. Sugerimos que a impressão de que o metilfenidato melhora o desempenho cognitivo em pessoas jovens e saudáveis se deve ao seu efeito subjetivo de bem-estar.

RESUMO

The current Brazilian situation is such that it is difficult to obtain a worldwide evaluation of failure in education, intervention, or prevention programs. How fragile Brazil's anti-doping system is, its appropriateness as well as its relevance, with needed policy infrastructures for achieving the selected goals, and how wide the gap is between education and prevention program effectiveness between high-performance athletes and recreational practitioners who just want to look good. An additional concern, and ever present flaw regarding Brazil's "common sportsman" in day-to-day society is their not receiving known and necessary "sports education," enabling the development of an "at-risk" population for self-harm. Reflections on public health policy are noted.

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RESUMO

Doping, used to improve sports performance, is legally prohibited. This paper describes Brazilian regulations, resolutions, and Federal laws addressing the issue of doping and antidoping which were collected in 2012 from official websites. We conclude that Brazilian laws have constrained doping, and have been updated over the years to conform to worldwide legal guidelines. Study limitations are noted.

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RESUMO

O efeito ergogênico da cafeína em exercícios anaeróbios permanece controverso, parecendo ser dependente da duração do exercício, protocolo utilizado e do estado de treinamento dos sujeitos estudados. Assim, esta revisão surge na tentativa de analisar as pesquisas que investigaram o efeito da cafeína no desempenho de exercícios predominantemente anaeróbios e principalmente, discutir a respeito dos diferentes métodos utilizados, objetivando verificar de que forma isto pode explicar os resultados controversos, além de apresentar os possíveis mecanismos de ação da cafeína. Em simples esforços anaeróbios com duração inferior a 30 segundos, a cafeína parece exercer influência no desempenho apenas em atletas, no entanto, mais estudos precisam ser feitos nesta população. Já em exercícios um pouco mais extensos (de 60 até 180 segundos), a cafeína parece melhorar o desempenho independentemente do estado de treinamento. O mecanismo de ação ainda não está claro, entretanto, existem evidências que a ação da cafeína é multifatorial, visto que esta substância altera características centrais e periféricas. Dentre as principais características, a cafeína atua como receptor antagônico de adenosina, aumentando a excitabilidade do sistema nervoso central e alterando a percepção de esforço e de dor, além disso, diminui a sensibilidade do retículo sarcoplasmático na liberação do cálcio. Novas pesquisas que investiguem o papel da cafeína em exercícios anaeróbios devem ser realizadas, utilizando amostras de indivíduos adaptados ao treinamento anaeróbio, bem como protocolos semelhantes ao de esportes cíclicos a fim de esclarecer os resultados contraditórios.

The ergogenic effect of caffeine on anaerobic exercises remains controversial. Such effect seems to depend on exercise duration, test protocol, and training status of the subjects studied. Thus, the objective of this review of the literature was to analyze studies investigating the effect of caffeine on the performance of anaerobic exercises and to discuss the different methods used to measure this effect in order to try to explain controversial results, as well as to present possible mechanisms of action of caffeine. During anaerobic exercises lasting less than 30 seconds, caffeine appears to have an influence only on the performance of athletes; however, there is need of further studies with this population. Nevertheless, in longer exercises (from 60 to 180 seconds), caffeine seems to improve performance regardless of the training status. The mechanism of action remains unclear; however, there is evidence that the action of caffeine is multifactorial, since this substance changes central and peripheral characteristics. Among the main characteristics, caffeine acts as an adenosine receptor antagonist, increasing the excitability of the central nervous system and changing the perception of effort and pain, in addition to reducing the sensitivity of the sarcoplasmic reticulum during calcium release. Further studies investigating the role of caffeine in anaerobic exercises should be conducted using anaerobically trained individuals and protocols similar to those of cyclic sports in order to clarify the contradictory results.