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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

sexta-feira, 30 de setembro de 2011

Judô Brasileiro em Sheffield

http://sportv.globo.com/site/programas/sportv-news/noticia/2011/09/judo-brasileiro-escolhe-sheffield-como-quartel-general-na-inglaterra.html

Eletroestimulação e recuperação de atletas de judô

J Athl Train. 2011;46(4):386-94.


Comparison of recovery strategies on maximal force-generating capacity and electromyographic activity level of the knee extensor muscles.

Zarrouk N, Rebai H, Yahia A, Souissi N, Hug F, Dogui M.

Neurophysiologie de la Vigilance, de l'Attention et des Performances, Service d'Explorations Fonctionnelles du Système Nerveux, CHU Sahloul, Sousse, Tunisia;


Abstract
CONTEXT: With regard to intermittent training exercise, the effects of the mode of recovery on subsequent performance are equivocal.
OBJECTIVE: To compare the effects of 3 types of recovery intervention on peak torque (PT) and electromyographic (EMG) activity of the knee extensor muscles after fatiguing isokinetic intermittent concentric exercise.
DESIGN: Crossover study.
SETTING: Research laboratory. Patients or Other Participants: Eight elite judo players (age = 18.4 ± 1.4 years, height = 180 ± 3 cm, mass = 77.0 ± 4.2 kg). Intervention(s): Participants completed 3 randomized sessions within 7 days. Each session consisted of 5 sets of 10 concentric knee extensions at 80% PT at 120°/s, with 3 minutes of recovery between sets. Recovery interventions were passive, active, and electromyostimulation. The PT and maximal EMG activity were recorded simultaneously while participants performed isokinetic dynamometer trials before and 3 minutes after the resistance exercise. Main Outcome Measure(s): The PT and maximal EMG activity from the knee extensors were quantified at isokinetic velocities of 60°/s, 120°/s, and 180°/s, with 5 repetitions at each velocity.
RESULTS: The reduction in PT observed after electromyostimulation was less than that seen after passive (P < .001) or active recovery (P < .001). The reduction in PT was less after passive recovery than after active recovery (P < .001). The maximal EMG activity level observed after electromyostimulation was higher than that seen after active recovery (P < .05).
CONCLUSIONS: Electromyostimulation was an effective recovery tool in decreasing neuromuscular fatigue after high-intensity, intermittent isokinetic concentric exercise for the knee extensor muscles. Also, active recovery induced the greatest amount of neuromuscular fatigue.

http://docserver.ingentaconnect.com/deliver/connect/nata/10626050/v46n4/s8.pdf?expires=1317409023&id=64661649&titleid=41000054&accname=Guest+User&checksum=F32C1DAAE1C336CA7B101573E6AEB3C6

segunda-feira, 26 de setembro de 2011

Manutenção dos resultados competitivos no judô

TRACKING 10-YEAR COMPETITIVE WINNING PERFORMANCE OF JUDO ATHLETES ACROSS AGE GROUPS1


URSULA F. JULIO, MONICA Y. TAKITO, LEANDRO MAZZEI, BIANCA MIARKA
School of Physical Education and Sport, University of São Paulo

STANISLAW STERKOWICZ
Department of Theory and Methodology of Combat Sports Academy of Physical Education in Krakow

EMERSON FRANCHINI
School of Physical Education and Sport University of São Paulo

Summary
Little information is available concerning early specialization and competitive success in judo across the early training years. Thus, the present objective was to verify the stability of individual competitive performance of a state-level championship for judo athletes who had been previously successful. For this, 406 athletes from six age groups (9 to 20+ years old) of each sex were followed for 10 years. Using recorded data from the São Paulo State Judo Federation beginning in 1999, the scores and standings for these judo players were analyzed. The proportion of medal winners during this period was not constant, differing from the grand mean in all groups of both 204 males and 202 females. At the end of this period, only 7% of the male and 5% of the female athletes had maintained their competitive levels. Successful competitive performance in early judo competition was not associated with success later in adulthood.

sábado, 24 de setembro de 2011

Hidratação em atletas de judô adolescentes

Int J Sports Physiol Perform. 2011 Aug 30. [Epub ahead of print]


Hydration Status in Adolescent Judo Athletes Before and After Training in the Heat.

Rivera-Brown AM, De Félix-Dávila RA.

Center for Sports Health and Exercise Sciences at the Albergue Olímpico, Department of Physical Medicine, Rehabilitation and Sports Medicine, University of Puerto Rico School of Medicine, San Juan, Puerto Rico.

Abstract
Adolescent judo athletes that train in tropical climates may be in a persistent state of dehydration because they frequently restrict fluids during daily training sessions to maintain or reduce their body weight and are not given enough opportunities to drink.
PURPOSE: Determine the body hydration status of adolescent judo athletes before (PRE), immediately after (POST), and 24 hours after (24H) a training session and document sweat Na+ loss and symptoms of dehydration.
METHODS: Body mass and urine color and specific gravity (USG) were measured PRE, POST, and 24H after a training session in a high heat stress environment (29.5 ± 1.0°C; 77.7 ± 6.1% RH) in 24 adolescent athletes. Sweat sodium loss was also determined. A comparison was made between mid pubertal (MP) and late pubertal (LP) subjects.
RESULTS: The majority of the subjects started training with a significant level of dehydration. During the training session, MP subjects lost 1.3 ± 0.8% of their pre-training body mass while LP subjects lost 1.9 ± 0.5% (P < 0.05). Sweat sodium concentration was 44.5 ± 23.3 mmol/L. Fluid intake from a water fountain was minimal. Subjects reported symptoms of dehydration during the session which in some cases persisted throughout the night and the next day. The 24H USG was 1.028 ± 0.004 and 1.027 ± 0.005 g/ml for MP and LP, respectively.
CONCLUSIONS: Adolescent judo athletes arrive to practice with a fluid deficit, do not drink enough during training, and experience symptoms of dehydration which may compromise the quality of training and general well being.

sexta-feira, 16 de setembro de 2011

Reuniões grupais canceladas até 18/11

Para reuniões individuais, agendar por e-mail

Semana do TKD no pubmed

J Strength Cond Res. 2011 Sep 7. [Epub ahead of print]


Anthropometrical, physiological, and tracked power profiles of elite taekwondo athletes 9 weeks before the Olympic competition phase.

Ball N, Nolan E, Wheeler K.

1Department of Sport Studies, National Institute of Sports Studies, University of Canberra, Bruce, Australia; and 2Strength and Conditioning Department, Australian Institute of Sport, Bruce, Australia.

Abstract

Ball, N, Nolan, E, and Wheeler, K. Anthropometrical, physiological, and tracked power profiles of elite taekwondo athletes 9 weeks before the Olympic competition phase. J Strength Cond Res 25(X): 000-000, 2011-Physiological, anthropometric, and power profiling data were retrospectively analyzed from 4 elite taekwondo athletes from the Australian National Olympic team 9 weeks from Olympic departure. Power profiling data were collected weekly throughout the 9-week period. Anthropometric skinfolds generated a lean mass index (LMI). Physiological tests included a squat jump and bench throw power profile, bleep test, 20-m sprint test, running &OV0312;O2max test, and bench press and squat 3 repetition maximum (3RM) strength tests. After this, the athletes power, velocity, and acceleration profile during unweighted squat jumps and single-leg jumps were tracked using a linear position transducer. Increases in power, velocity, and acceleration between weeks and bilateral comparisons were analyzed. Athletes had an LMI of 37.1 ± 0.4 and were 173.9 ± 0.2 m and 67 ± 1.1 kg. Relatively weaker upper body (56 ± 11.97 kg 3RM bench press) compared to lower body strength (88 ± 2.89 kg 3RM squat) was shown alongside a &OV0312;O2max of 53.29 ml·min·kg, and a 20-m sprint time of 3.37 seconds. Increases in all power variables for single-leg squat and squat jumps were found from the first session to the last. Absolute peak power in single-leg squat jumps increased by 13.4-16% for the left and right legs with a 12.9% increase in squat jump peak power. Allometrically scaled peak power showed greater increases for single-leg (right leg: 18.55%; left: 23.49%) and squat jump (14.49%). The athlete's weight did not change significantly throughout the 9-week mesocycle. Progressions in power increases throughout the weeks were undulating and can be related to the intensity of the prior week's training and athlete injury. This analysis has shown that a 9-week mesocycle before Olympic departure that focuses on core lifts has the ability to improve power considerably.

J Strength Cond Res. 2011 Sep 8. [Epub ahead of print]


Impact Force and Time Analysis Influenced by Execution Distance in a Roundhouse Kick to the Head in Taekwondo.

Estevan I, Alvarez O, Falco C, Molina-García J, Castillo I.

1Department of Physical Activity and Sport Sciences, Catholic University of Valencia, Valencia, Spain; 2Cheste Sport Medicine Center, Valencia Sports Council, Valencian International University, Valencia, Spain; 3Department of Music, Plastic and Body Expression University of Valencia, Valencia, Spain; and 4Department of Social Psychology, University of Valencia, Valencia, Spain.

Abstract

Estevan, I, Álvarez, O, Falco, C, Molina-García, J, and Castillo, I. Impact force and time analysis influenced by execution distance in a roundhouse kick to the head in Taekwondo. J Strength Cond Res 25(X): 000-000, 2011-The execution distance is a tactic factor that affects mechanical performance and execution technique in taekwondo. This study analyzes the roundhouse kick to the head by comparing the maximum impact force, execution time, and impact time in 3 distances according to the athletes' competition level. It also analyzes the relationship between impact force and weight in each group. It examines whether the execution distance affects the maximum impact force, execution time, and impact time, in each level group or 2 different competition levels. Participants were 27 male taekwondo players (13 medallists and 14 nonmedallists). The medallists executed the roundhouse kick to the head with greater impact force and in a shorter execution time than did the nonmedallists when they kicked from any distance different to their combat distance. However, the results showed that the execution distance is influential in the execution time and impact time in the nonmedallist group. It is considered appropriate to orientate the high-level competitors to train for offensive actions from any distance similar to the long execution distance because it offers equally effectiveness and a greater security against the opponent. Also, practitioners should focus their training to improve time performance because it is more affected by distance than impact force.


Int J Sports Physiol Perform. 2011 Sep;6(3):344-57.


The activity profile in international taekwondo competition is modulated by weight category.

Bridge CA, Jones MA, Drust B.

Sport and Exercise Research Group, Edge Hill University, Ormskirk, UK.

Abstract
PURPOSE: To examine the activity profiles of elite male competitors during international Taekwondo competition in relation to fin, feather, and heavy weight categories.
METHODS: Twelve male Taekwondo competitors equally representing fin, feather, and heavy weight divisions were studied during the 2005 World Taekwondo Championships using a time-motion system developed to analyze the activities and activity phases. The frequency and duration of activities were recorded and assimilated into four independent activity phases: fighting activity, preparatory activity, nonpreparatory activity and stoppage activity. The total number of exchanges and kicks were also calculated for each combat.
RESULTS: For all weight groupings the mean ± SD fighting time was 1.7 ± 0.3 s, preparatory time 6.4 ± 2.1 s, nonpreparatory time 3.0 ± 0.6 s, referee stoppage time 2.8 ± 0.9 s and 28 ± 6 exchanges and 31 ± 7 kicks were performed. Differences in the mean fighting time (fin: 1.4 ± 0.2 s vs heavy: 1.8 ± 0.3 s; P = .03; effect size [ES] = 1.57), preparatory time (fin: 5.3 ± 1.0 s vs feather: 8.2 ± 2.6 s; P = .03; ES = 1.47) and the total number of exchanges (feather: 24 ± 6 vs heavy: 32 ± 5; P = .03; ES = 1.44) were identified between the weight categories.
CONCLUSIONS: The activity profile in international Taekwondo competition was modulated by competitors' weight category. These findings suggest that conditioning sessions may need to be specialized to the requirements of specific weight categories.

quarta-feira, 14 de setembro de 2011

História do judô feminino no Japão

Int J Hist Sport. 2011;28(7):1016-029.


Reinterpreting the history of women's judo in Japan.

Miarka B, Marques JB, Franchini E.

University of Säo Paulo, Brazil.

Abstract

This paper reassesses the role of women in judo in Japan, from its secluded and restricted beginnings in the late nineteenth century to the gradual changes in gender and social paradigms triggered by the influence of Western feminist struggle from the 1960s onwards. Judo has been considered in theory an inclusive martial art because its creator, Jigoro Kano, stressed safety, etiquette and moral teachings irrespective of age, size or gender of its adherents. However, the social and cultural environment in Japan has traditionally discriminated against women both outside and inside the dojo (training place). We treat this issue historically, considering the broader context of the Japanese social, political and cultural developments.

terça-feira, 13 de setembro de 2011

Contribuição energética durante o SJFT: centésimo artigo publicado : )

International Journal of Sports Physiology and Performance, v. 6, n.3, p.334-343, 2011.

Emerson Franchini, Stanislaw Sterkowicz, Urszula Szmatlan-Gabrys, Tomasz Gabrys, Michal Garnys


 

Energy System Contributions to the Special Judo Fitness Test

Purpose:This study investigated the energy system contributions of judo athletes to the Special Judo Fitness Test (SJFT). Methods: Fourteen male judo athletes performed the SJFT, which comprised three periods of judo activity (A = 15 s, B and C = 30 s) interspersed with 10 s rest intervals. During this test, one athlete threw two others positioned 6 m from each other using the ippon-seoi-nage technique. The fractions of the aerobic, anaerobic alactic and anaerobic lactic systems were calculated based on oxygen uptake, the fast component of excess postexercise oxygen uptake, and changes in net blood lactate, respectively. The contribution of the three energy systems was compared using a repeated measures analysis of variance and Bonferroni’s multiple comparisons test. Compound symmetry, or sphericity, was determined by Mauchly’s test. A level of significance of 5% (P < .05) was adopted in all analyses. Results: The alactic energy system presented a higher (F = 20.9; P < .001; power observed = 1.0) contribution (86.8 ± 23.6 kJ; 42.3 ± 5.9%) during the test when compared with both aerobic (57.1 ± 11.3 kJ; 28.2 ± 2.9%) and lactic (58.9 ± 12.1 kJ; 29.5 ± 6.2%) energy systems (P < .001 for both comparisons). Conclusions: The higher alactic contribution seems to be a consequence of the high-intensity efforts performed during the test, and its intermittent nature. Thus, when using the SJFT, coaches are evaluating mainly their athletes’ anaerobic alactic system, which can be considered to be the most predominant system contributing to the actions (techniques) performed in the match.



Keywords: combat sports, test, evaluation, high-intensity intermittent exercise



domingo, 11 de setembro de 2011

Participação no judô como forma de aculturação de brasileiros no Japão

Dica do Fabrício:
The Role of Leisure in the Assimilation of Brazilian Immigrants into Japanese Society: Acculturation and Structural Assimilation through Judo Participation

Eiji Ito1, Haruo Nogawa2, Kaoru Kitamura2 and Gordon J. Walker1
1Faculty of Physical Education and Recreation, University of Alberta,

E-488 Van Vliet Centre, Edmonton, Alberta, T6G 2H9, Canada

eiji@ualberta.ca

2Graduate School of Health and Sports Science, Juntendo University,

1-1 Hiragagakuendai, Inzai-shi, Chiba, 2701695, Japan

[Received May 26, 2010; Accepted December 20, 2010; Published online January 20, 2011]
 
The purpose of this study was to examine how a leisure activity (i.e., judo) aŠected the assimilation of Brazilian immigrants in Japan. Researchers hypothesized that judo participation would aŠect the processes of assimilation, particularly acculturation and structural assimilation. Based on the results of observations, informal interviews, and questionnaires conducted with Brazilian judo participants and their parents as well as the results of formal interviews held with the judo instructors, the hypothesis was conˆrmed. This result suggests that there are multiple ways in which leisure organizations can work with immigrants to help them adjust to a new society. This study contributes to the growing, yet still understudied, area of immigrant leisure esearch, and it provides a unique perspective by examining the experiences of Brazilian immigrants living in Japan.

Impossible judo: vídeos com atletas evitando a queda

Dica do Juan Jimenez
http://www.youtube.com/watch?v=1Bu58TVTxW4

http://www.youtube.com/watch?v=X1ta-o1-C4o&feature=related

segunda-feira, 5 de setembro de 2011

quinta-feira, 1 de setembro de 2011

Relatório do VII Judo Research Symposium; de autoria do Fabrício

https://docs.google.com/viewer?a=v&pid=sites&srcid=ZGVmYXVsdGRvbWFpbnxib2xldGltb3NvdG9nYXJpfGd4OjczNjRjYzJmNzNjMjgxNGI

Capacidades motoras básicas e desempenho de karatekas

Coll Antropol. 2010 Dec;34(4):1341-5.


The impact of basic motor abilities on the specific motoricity performance in elite karateka.

Katić R, Blazević S, Zagorac N.

University of Split, Faculty of Kinesiology, Split, Croatia. ratko.katic@gmail.com


Abstract

The aim of the study was to identify motor structures that determine high performance in karate. The study included a group of 85 karateka aged 18-29 years, competing as senior category athletes within the Croatian Karate Society. A battery of 22 motor tests (9 basic motoricity tests and 13 specific motoricity tests) were used. Factor analysis of the basic motor variables pointed to the existence of three significant factors: coordination, explosive strength and movement frequency; whereas factor analysis of the specific motoricity area indicated two significant factors, i.e., factor of technical efficiency and factor of specific agility. Canonical correlation analysis showed the isolated set of basic motor factors to significantly determine both technical efficiency and specific agility-mobility of the karateka, with a predominance of the explosive strength (force) factor, followed by the speed and coordination factors.