terça-feira, 30 de junho de 2015

Artigo sobre BJJ na edição de julho do JSCR

Competição simulada de BJJ: desempenho físico, estrutura temporal, análises técnicas e táticas e respostas perceptivas
Journal of Strength & Conditioning Research:
July 2015 - Volume 29 - Issue 7 - p 2015–2025
doi: 10.1519/JSC.0000000000000819
Brazilian Jiu-Jitsu Simulated Competition Part II: Physical Performance, Time-Motion, Technical-Tactical Analyses, and Perceptual Responses
Andreato, Leonardo V.1,2; Julio, Ursula F.1; Gonçalves Panissa, Valeria L.1; Del Conti Esteves, João V.3; Hardt, Felipe1; Franzói de Moraes, Solange M.4; Oliveira de Souza, Camila3; Franchini, Emerson1
The aim of this study was to analyze performance, time structure, technical actions, and perceptual responses in Brazilian jiu-jitsu athletes during a simulated competition. For this purpose, 10 athletes were analyzed in a simulated competition (4 matches of 10 minutes). Physical tests and scales of the perception of effort and recovery were applied. The matches were recorded for the purpose of technical-tactical analysis and to determine the time structure. The main results show that in the simulated competition, reaction time (F2.5,17.6 = 2.7; p = 0.087; η2 = 0.28) and flexibility (F7,63 = 1.5; p = 0.172; η2 = 0.15) were unchanged across the matches. An analysis of variance showed a significant difference for grip endurance using the kimono (F2.0,15.9 = 8.1; p = 0.004; η2 = 0.50), which was not confirmed by the Bonferroni test. Jump height indicated postactivation potentiation after match 2 (F7,63 = 3.5; p = 0.003; η2 = 0.28). The maximal isometric handgrip strength in the dominant hand (F3.2,28.6 = 2.9; p = 0.049; η2 = 0.24) and in the nondominant hand (F7,63 = 3.8; p = 0.002; η2 = 0.30) showed a decline after matches 3 and 4. Although these data indicate the onset of fatigue, the effort/pause ratio of the matches was not altered (F3,12 = 0.6; p = 0.624; η2 = 0.13). The perceptions of effort (F3,27 = 0.9; p = 0.469; η2 = 0.09) and recovery (F1.9,17.0 = 2.4; p = 0.125; η2 = 0.21) and the degree of fatigue reported (F1.5,13.8 = 0.5; p = 0.588; η2 = 0.05) did not change during the simulated competition. Thus, it may be concluded that the execution of successive matches causes a decline in maximal isometric handgrip strength. No changes in the time structure of the matches or in the perceptual responses were observed.

sexta-feira, 26 de junho de 2015

Trabalho com atletas da seleção brasileira de boxe


STRENGTH AND POWER QUALITIES ARE HIGHLY ASSOCIATED WITH PUNCHING IMPACT IN ELITE AMATEUR BOXERS.
Loturco, Irineu; Nakamura, Fabio Yuzo; Artioli, Guilherme Giannini; Kobal, Ronaldo; Kitamura, Katia; Cal Abad, Cesar Cavinato; Cruz, Igor Freitas; Romano, Felipe; Pereira, Lucas Adriano; Franchini, Emerson
Journal of Strength & Conditioning Research

Abstract

This study investigated the relationship between punching impact and selected strength and power variables in 15 amateur boxers from the Brazilian National Team (9 men and 6 women). Punching impact was assessed in the following conditions: 3 jabs starting from the standardized position (FJ), 3 crosses starting from the standardized position (FC), 3 jabs starting from a self-selected position and (SSJ) and 3 crosses starting from a self-selected position (SSC). For punching tests, a force platform (1.02 m x 0.76 m) covered by a body shield was mounted on the wall at a height of 1 m, perpendicular to the floor. The selected strength and power variables were: vertical jump height (in squat jump [SJ] and countermovement jump [CMJ]), mean propulsive power (MPP) in the jump squat (JS), bench press (BP), and bench throw (BT), maximum isometric force (MIF) in squat and BP, and rate of force development (RFD) in the squat and BP. Sex and position main effects were observed, with higher impact for males compared to females (P< 0.05) and the self-selected distance resulting in higher impact in the jab technique compared to the fixed distance (P< 0.05). Finally, the correlations between strength/power variables and punching impact indices ranged between 0.67 and 0.85. Due to the strong associations between punching impact and strength/power variables (e.g., lower limb muscle power), this study provides important information for coaches to specifically design better training strategies to improve punching impact.