À minha família, pela paciência, compreensão e apoio. A um grande professor, amigo e companheiro, Maurício Teodoro de Souza, percursor desta caminhada. Aos colegas Profa. Rita de Cássia Garcia Verenguer, Profa. Jeane Barcelos e Prof. Eduardo Bacelar, minha gratidão pelo companheirismo. Ao Prof. Dr. José Elias de Proença, meu inestimável agradecimento. Aos amigos Júlio Serrão e Fernando Marcondes, companheiros... Ao IME-USP, que através do CEA na pessoa do Prof. Dr. Nelson Ithiro Tanaka e do acadêmico Alberto Foltran Berti, colaborarou para o desenvolvimento estatístico deste estudo, com muita paciência, carinho e amizade. Aos funcionários da EEFEUSP: Lúcia, Lourdes, Célia e Marco. Ao E.C. Pinheiros e particularmente ao Prof. Silvio e seus atletas, bem como a todos atletas e comissão técnica do E.C. Banespa. Ao Montanaro, por toda a sua receptividade, confiança e amizade. Aos profissionais que colaboraram na coleta de dados, a minha sempre disposição e amizade.
Background
The efficacy of sodium citrate supplementation (SC) in exercise performance is unclear. Therefore, the aim of this study was to investigate the effect of SC on skilled tennis performance.
Methods
Ten Brazilian nationally-ranked young male tennis players (age: 17 ± 1 yrs.; stature: 176.7 ± 5.2 cm; body mass: 68.4 ± 7.9 kg) participated in this crossover, placebo-controlled, double-blind study. Upon arrival, at baseline, in both experimental sessions blood was collected, then subjects ingested either sodium citrate (SC - 0.5 g
.
kg
−1
BM in capsules of 500 mg) or a placebo (PLA). Two hours later, pre-match blood was collected then skills tests (skill tennis performance test - STPT, repeated-sprint ability shuttle test - RSA) were performed followed by a 1-h simulated match. Immediately following the match, blood was again collected, and STPT, and RSA were administered.
Results
All metabolic parameters (i.e. base excess, pH, bicarbonate, and blood lactate) increased (
p
< 0.001) from baseline to pre-match and post-match in SC condition. Each metabolic parameter was greater (p < 0.001) in SC compared to PLA condition at both pre- and post-match. The SC condition elicited a greater (
p
< 0.01) shot consistency at post-match in the STPT vs. PLA condition (SC: 58.5 ± 14.8% vs. PLA: 40.4 ± 10.4%). A greater (
p
< 0.001) amount of games won was observed in the simulated match for SC condition vs. PLA condition (SC: 8.0 ± 1.6 vs. PLA: 6.0 ± 1.7). Additionally, the games won during the simulated match in SC condition was positively correlated with percentage shot consistency (r = 0.67,
p
< 0.001).
Conclusions
The current findings suggest that SC supplementation is an effective ergogenic aid to enhance skilled tennis performance.
Embora no Brasil o judô possua tradição olímpica, pouco se conhece sobre os aspectos que contribuem para o desenvolvimento do talento no cenário nacional. Sendo assim, o objetivo do presente estudo foi analisar os fatores de apoio psicossocial presentes no desenvolvimento de judocas brasileiros talentosos do sexo masculino. Para tanto, se utilizou uma amostra de seis judocas, pertencentes à seleção brasileira nos Jogos Olímpicos de Atenas, 2004. A pesquisa foi constituída através de um delineamento qualitativo, que utilizou como instrumento uma entrevista composta por três perguntas abertas. Para a análise dos resultados foi utilizado o "Discurso do Sujeito Coletivo". Os discursos indicaram a importância dos fatores relacionados : a) ao apoio da família; b) ao prazer pela prática; e c) a determinação dos judocas, corroborando com a literatura internacional no que tange a relevância dos fatores psicossociais para o desenvolvimento do talento em diferentes domínios do conhecimento.
The aim of this study was to examine the influence of hormonal status, anthropometric profile, sexual maturity level, and physical performance on the technical abilities of 40 young male soccer players during small-sided games (SSGs). Anthropometric profiling, saliva sampling, sexual maturity assessment (Tanner scale), and physical performance tests (Yo-Yo and vertical jumps) were conducted two weeks prior to the SSGs. Salivary testosterone was determined by the enzyme-linked immunosorbent assay method. Technical performance was determined by the frequency of actions during SSGs. Principal component analyses identified four technical actions of importance: total number of passes, effectiveness, goal attempts, and total tackles. A multivariate canonical correlation analysis was then employed to verify the prediction of a multiple dependent variables set (composed of four technical actions) from an independent set of variables, composed of testosterone concentration, stage of pubic hair and genitalia development, vertical jumps and Yo-Yo performance. A moderate-to-large relationship between the technical performance set and the independent set was observed. The canonical correlation was 0.75 with a canonical R2 of 0.45. The highest structure coefficient in the technical performance set was observed for tackles (0.77), while testosterone presented the highest structure coefficient (0.75) for the variables of the independent set. The current data suggest that the selected independent set of variables might be useful in predicting SSG performance in young soccer players. Coaches should be aware that physical development plays a key role in technical performance to avoid decision-making mistakes during the selection of young players.
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