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Quem sou eu

São Paulo, São Paulo, Brazil
Professor da EEFE-USP; Praticante e Pesquisador de Judô; Preparador físico de atletas de modalidades esportivas de combate.

Arquivo do blog

quinta-feira, 10 de março de 2011

Sistemas complexos e criatividade no esporte

Nonlinear Dynamics Psychol Life Sci. 2011 Apr;15(2):175-206.

Constraints-induced Emergence of Functional Novelty in Complex Neurobiological Systems: A Basis for Creativity in Sport.
Hristovski R, Davids K, Araujo D, Passos P.
Abstract
In this paper we present a model of creativity captured as exploration and production of novel and functionally efficient behaviors, based on the statistical mechanics of disordered systems. In support of the modelling, we highlight examples of creative behaviors from our research in sports like boxing and rugby union. Our experimental results show how manipulation of practice task constraints changes the exploratory breadth of the hierarchically soft-assembled action landscape. Because of action metastability and differing task constraints, the specificity of each assembled movement configuration is unique. Empirically, a movement pattern's degree of novelty may be assessed by the value of the order parameter describing action. We show that creative and adaptive movement behavior may be induced by at least two types of interven-tions, based on relaxing task constraints which we term direct and indirect. Direct relaxing is typically a function of changing task constraints so that the number of affordances that can satisfy goal constraints increases. Indirect relaxing of constraints occurs when a habitual action is suppressed by, for example, stringent instructional constraints during sports training. That suppression simultaneously relaxes other correlated constraints that enable larger exploratory capacity and new affordances to emerge for the athlete or team.

quinta-feira, 3 de março de 2011

Suplementação de zinco em wrestlers

Biol Trace Elem Res. 2011 Mar 1. [Epub ahead of print]


Effects of Exercise and Zinc Supplementation on Cytokine Release in Young Wrestlers.
Kara E, Ozal M, Gunay M, Kilic M, Baltaci AK, Mogulkoc R.
Hasan Dogan High School of Physical Education and Sports, Karabuk University, Karabuk, Turkey, kara.ersan@yahoo.com.

Abstract
The present study aims to examine the effect of zinc supplementation on the release of some cytokines in young wrestlers actively involved in wrestling. A total of 40 male subjects of the same age group were included in the study: half were wrestlers and the other half were not involved in sports. The subjects were equally divided into four groups and treated during an 8-week period as follows: group 1, zinc-supplemented athletes; group 2, non-supplemented athletes; group 3, zinc-supplemented sedentary subjects, and group 4, non-supplemented sedentary group. Blood samples were taken from each subject at the beginning and at the end of the study period. The serum tumor necrosis factor-α (TNF-α), interleukin-2 (IL-2), and interpheron-γ levels (IFN-γ) were determined using the enzyme-linked immunosorbent assay method. At the beginning of the study, there were no significant differences of the measured parameters between the four study groups. At the end of the study, the levels of TNF-α, IL-2, and IFN-γ were significantly higher in the two zinc-supplemented groups compared to those that did not receive supplementation, regardless of the activity status (p < 0.01).