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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.

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quarta-feira, 24 de outubro de 2012

Uso de atividades motoras complexas no treinamento de boxeadores jovens

Technical performance effectiveness subsequent to complex motor skills training in young boxers

Said El Ashkera*
pages 475-484
Received: 07 Apr 2011
Accepted: 05 Jun 2011
Version of record first published: 01 Nov 2011
Article Views: 47


Boxing is a sport that comprises a wide variety of integrated offensive, defensive and counter-attack skills performed in an unpredictable environment. Mastering the variety of complex motor skills (CMS) that are required in a boxing match allows the player to employ the best motor performance in most positions of the actual game. This study aimed to assess the associations between implementing CMS versus simple motor skill (SMS) training and the subsequent changes in physical, technical and technical performance effectiveness (TPE) variables in junior boxers. We employed an experimental design that comprised two groups (each 20 males, mean age = 15.22±0.62 years). For 12 weeks, intervention boxers received CMS training, while controls received traditional SMS training. Physical, technical and TPE variables were measured before and after the training programs. Although the two groups were of similar abilities at baseline, there were statistically significant differences (P<0 .05=".05" abilities="abilities" absolute="absolute" across="across" advantage="advantage" and="and" better="better" between="between" boxers="boxers" cms="cms" contribute="contribute" control="control" could="could" developing="developing" differences="differences" enhance="enhance" exhibited="exhibited" favourable="favourable" group.="group." group="group" i.e.="i.e." improvements="improvements" in="in" intervention="intervention" junior="junior" measures="measures" more="more" of="of" or="or" p="p" performance.="performance." physical="physical" positively="positively" post="post" ratios="ratios" relative="relative" technical="technical" terms="terms" the="the" their="their" to="to" tpe.="tpe." values="values" variables="variables">

segunda-feira, 22 de outubro de 2012

Karate e controle postural

Is karate effective in improving postural control?
Davide Filingeri 1, Antonino Bianco 2, Daniele Zangla 3, Antonio Paoli 4, Antonio Palma 5
1 - Environmental Ergonomics Research Centre, Loughborough University, UK
2 - Department of Sports Science (DISMOT), University of Palermo, Palermo, Italy | School of Sport, CONI Sicilia, Palermo, Italy 
3 - Department of Sports Science (DISMOT), University of Palermo, Palermo, Italy
4 - Department of Anatomy and Physiology, Physiology Section, Padova, Italy
5 - Department of Sports Science (DISMOT), University of Palermo, Palermo | School of Sport, CONI Sicilia, Palermo, Italy 
Arch Budo 2012; 8(4):
Manuscript ID: 883521
Article type: Review article
Abstract provided by Publisher  
Background and Study Aim: Performing complex motor skills, such as the ones performed by karate athletes, requires a great sense of balance. Because the posturo-kinetic performance seems to be improved by sport practice, especially by sports involving a lot of posturokinetic activities, the aim of this review was to critically analyse the scientific literature in order to appraise whether any positive correlation between karate and improved postural control is scientifically supported.
Material and Methods: The online search engines Scirus and Medline were used for generating the data. A comprehensive literature search was conducted based on the following keywords: “karate”, “postural control” and “body sway”. Results were collected and filtered manually.
Results: Four articles were identified related to karate practice and postural control, covering a period between 1998 and 2009. Although different experimental approaches were used to investigate this concept, overall the results of these studies confirm the effectiveness of karate in improving postural control.
Conclusions: Practicing karate seems to elicit long term improvements in postural control. However, a much deeper approach to this fighting sport, which would take into account its technical specificities (e.g. kata & kumite), is required in order to increase our understanding of the posture-kinetic impact of this relatively unexplored sport activity.

domingo, 21 de outubro de 2012

Suplementação de arginina em lutadores de BJJ

 2012 Jun 26;9(1):30. [Epub ahead of print]

A sportomics strategy to analyze the ability of arginine to modulate both ammonia and lymphocyte levels in blood after high-intensity exercise.



BACKGROUND: Exercise is an excellent tool to study the interactions between metabolic stress and the immune system. Specifically, high-intensity exercises both produce transient hyperammonemia and influence the distribution of white blood cells. Carbohydrates and glutamine and arginine supplementation were previously shown to effectively modulate ammonia levels during exercise. In this study, we used a short-duration, high-intensity exercise together with a low carbohydrate diet to induce a hyperammonemia state and better understand how arginine influences both ammonemia and the distribution of leukocytes in the blood.


Brazilian Jiu-Jitsu practitioners (men, n = 39) volunteered for this study. The subjects followed a low-carbohydrate diet for four days before the trials and received either arginine supplementation (100 mg.kg-1 of body mass.day-1) or a placebo. The intergroup statistical significance was calculated by a one-way analysis of variance, followed by Student's t-test. The data correlations were calculated using Pearson's test.


In the control group, ammonemia increased during matches at almost twice the rate of the arginine group (25 mmol.L-1.min-1 and 13 mumol.L-1.min-1, respectively). Exercise induced an increase in leukocytes of approximately 75%. An even greater difference was observed in the lymphocyte count, which increased 2.2-fold in the control group; this increase was partially prevented by arginine supplementation. The shape of the ammonemia curve suggests that arginine helps prevent increases in ammonia levels.


These data indicate that increases in lymphocytes and ammonia are simultaneously reduced by arginine supplementation. We propose that increased serum lymphocytes could be related to changes in ammonemia and ammonia metabolism.

quarta-feira, 17 de outubro de 2012

Doenças infecciosas em esportes competitivos

 2012;47(5):516-8. doi: 10.4085/1062-6050-47.5.02.

Infectious disease outbreaks in competitive sports, 2005-2010.


Central Pathology Laboratory, Trinity College Dublin, St. James's Dublin, 8, Ireland. collinc6@tcd.ie.



Old, evolving, and new infectious agents continually threaten the participation of competitors in sports.


To provide an update of the medical literature on infectious disease outbreaks in sport for the last 5 years (May 2005-November 2010). Main Outcome Measure(s): A total of 21 outbreaks or clusters were identified.


Methicillin-resistant Staphylococcus aureus (n = 7, 33%; mainly community acquired) and tinea (trichophytosis: n = 6, 29%) were the most common pathogens responsible for outbreaks. Skin and soft tissue was the most common site of infection (n = 15, 71%).


The majority of outbreaks reported occurred in close-contact sports, mainly combat sports (ie, wrestlingjudo) and American football. Twelve outbreaks (57%) involved high school or collegiate competitors. Common community outbreak pathogens, such as influenza virus and norovirus, have received little attention.

terça-feira, 16 de outubro de 2012

Antropometria de atletas de TKD

Differences in body components and the significance of rehabilitation for taekwondo athletes compared to nonathletes

Volume 4, Number 3 (2012), 203-208DOI: 10.1007/s13530-012-0137-2


It is well known that the difference in individual characteristics showed between somatotypes and body components. However, few studies have investigated differences in body components and gender in taekwondo athletes compared to nonathletes. The present study is to analyze the body components and skin-fold thickness of taekwondo athletes compared to nonathletes, and to contribute to current research on rehabilitation and its application and significance. The fat body mass and impedance were significantly decreased in the taekwondo athlete compared with the nonathletic groups. The same values of the men group showed significantly greater decreases than those of the women in both the nonathlete and taekwondo groups. But, the lean body mass, basal metabolic rate (BMR), and total body water were significantly increased in the taekwondo athlete compared with the nonathletic groups. In terms of gender, the values of the men in both the nonathlete and taekwondo groups showed significantly greater increases than those of the women of both groups. However, there were no significant differences between the men and women skin-fold thickness data for all participants. Therefore, these results, in part, found that there was a difference in body components between taekwondo athletes and nonathletes. Also, when applying physical stimuli such as electrotherapy, ultrasound, and heat, the body components of each patient for healthy life need to be carefully considered.

domingo, 14 de outubro de 2012

Raiva entre atletas adolescentes

 2012 Mar;22(1):9-14.

Anger in Adolescent Boy Athletes: a Comparison among JudoKarate, Swimming and Non Athletes.


Sports Medicine Research Center, Tehran University of Medical Sciences, Tehran, Iran ; Department of Pediatrics, Tehran University of Medical Sciences, Tehran, Iran.



Karate and judo are originally Japanese martial arts which may have different influences on adolescents' behavior. This study was conducted to examine the total anger rate and its subscale-reactive anger, instrumental anger, and anger control-rates in young karateka and judoka.


A cross-sectional study was carried out in 11 to 19-year old boys. Adolescents included in the study were judoka (n=70), karateka (n=66), swimmers (n=59), and non athletes (n=96). One stage cluster sampling method was used to select judoka, karateka, and swimmers from sport clubs in Tehran. Students of governmental schools at the same area were chosen as the non-athletes group. The "Adolescent Anger Rating Scale" questionnaire was utilized to assess the anger rate.


The mean age of participants was 12.90(±2.06) years. The total anger rates were 45.40 (±5.61) in judoka, 41.53(±5.63) in karateka, 41.19(±5.33) in swimmers, and 45.44 (±8.58) in non athletes. In total anger scale karateka and swimmers had a significantly lower score compared to judoka and non athletes. In instrumental anger subscale the difference was significant just between karateka and non athletes. In reactive anger subscale judoka showed higher scores than swimmers. In anger control subscale the difference was significant between judoka and swimmers and also judoka and karateka. The difference of anger control between karateka and non athletes was significant.


The findings of this study propose a difference in the anger rate between judoka and karateka. In contrary to the results of previous studies, judo training may have no influence on anger control, while karate training could be beneficial.

quinta-feira, 11 de outubro de 2012

Experimento interessante: efeito do barulho sobre as decisões da arbitragem em lutas de Muay Thai com lutadores da casa e visitantes

 2012;3:346. Epub 2012 Sep 14.

The Impact of Crowd Noise on Officiating in Muay Thai: Achieving External Validity in an Experimental Setting.


Newman University College Birmingham, UK.


Numerous factors have been proposed to explain the home advantage in sport. Several authors have suggested that a partisan home crowd enhances home advantage and that this is at least in part a consequence of their influence on officiating. However, while experimental studies examining this phenomenon have high levels of internal validity (since only the "crowd noise" intervention is allowed to vary), they suffer from a lack of external validity, with decision-making in a laboratory setting typically bearing little resemblance to decision-making in live sports settings. Conversely, observational and quasi-experimental studies with high levels of external validity suffer from low levels of internal validity as countless factors besides crowd noise vary. The present study provides a unique opportunity to address these criticisms, by conducting a controlled experiment on the impact of crowd noise on officiating in a live tournament setting. Seventeen qualified judges officiated on thirty Thai boxing bouts in a live international tournament setting featuring "home" and "away" boxers. In each bout, judges were randomized into a "noise" (live sound) or "no crowd noise" (noise-canceling headphones and white noise) condition, resulting in 59 judgments in the "no crowd noise" and 61 in the "crowd noise" condition. The results provide the first experimental evidence of the impact of live crowd noise on officials in sport. A cross-classified statistical model indicated that crowd noise had a statistically significant impact, equating to just over half a point per bout (in the context of five round bouts with the "10-point must" scoring system shared with professional boxing). The practical significance of the findings, their implications for officiating and for the future conduct of crowd noise studies are discussed.

segunda-feira, 8 de outubro de 2012

Campeonato Paulista de Kendô

Dica do Guilherme Oliveira:

*** Campeonato Paulista de Kendo 2012 ***
Dia 14 de Outubro de 2012, no Parque Esportivo dos
Endereço: Rua Canuto de Abreu, s/n°, Tatuapé – SP
Data e horário: dia 14 de Outubro de 2012, a partir das 8h

sexta-feira, 5 de outubro de 2012

Soco no karate: diferenças entre homens e mulheres

 2012 Aug;115(1):228-40.

Sex differences in electromechanical delay during a punch movement.


Sport Sciences School of Rio Maior, Polytechnic Institute of Santarém, Rio Maior, Portugal. marioarf@gmail.com


This study assessed how sex of participant is related to electromechanical delay during a karate punch. Ten male (M age = 25.00 yr., SD = 3.02; M height=174.9 cm, SD=6.3; M weight = 71.13 kg, SD=9.35) and 8 female (M age = 27.4 yr., SD = 6.0; M height = 161.4 cm, SD = 5.1; M weight = 59.09 kg, SD = 7.00) karate athletes performed 10 ballistic punches to a target as hard as possible. Kinematic analysis and surface electromyographic (EMG) activity of the upper-limb muscles were recorded. Men had a significantly shorter electromechanical delay in the anterior portion of the deltoid, showing a larger effectiveness in the transfer of the contractile force for the beginning of movement. Agonist and antagonist relationships show intermuscular coordination differences between the sexes. Results revealed the existence of a different neuromuscular coordination pattern of motor control between men and women, although a similar kinematic pattern was expected due to karate practice.

segunda-feira, 1 de outubro de 2012

Home advantage no judô

Journal of Sports Sciences, 2012; 1–7, iFirst article
Home advantage in judo: A study of the world ranking list
In 2009, the International Judo Federation established a ranking system (RS) to classify athletes and to distribute the competitor quotas of the Olympic Games. However, the RS does not consider the home advantage. This issue has not been studied in judo, and its implications for the RS have not been determined. The objective was to verify the home advantage in judo in terms of winning a medal or the number of matches won. Therefore, 25 competitions that computed points for the RS in 2009 were analysed. Logistic regression analysis and the Poisson generalised linear model were used for the analyses, which included the relative quality of the athletes. The sample was composed only of athletes who had competed both at home and away. The odds ratio for winning medals was higher for athletes who competed at home for both males and females. The association between the number of matches won and competing at home was significant only for the male athletes. The home advantage was observed in the competitions that used the judo RS. Thus, it is likely that athletes from countries that host competitions using the RS have an advantage in terms of obtaining their Olympic classification.