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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

sábado, 31 de março de 2012

MMA e violência juvenil

Violence Vict. 2012;27(1):43-69.

Epidemiology of mixed martial arts and youth violence in an ethnically diverse sample.

Hishinuma ES, Umemoto KN, Nguyen TG, Chang JY, Bautista RP.

Department of Psychiatry, University of Hawai'i at Mānoa, Honolulu, Hawai'i 96813, USA. hishinumae@dop.hawaii.edu

Mixed martial arts' (MMAs) growing international popularity has rekindled the discussion on the advantages (e.g., exercise) and disadvantages (e.g., possible injury) of contact sports. This study was the first of its kind to examine the psychosocial aspects of MMA and youth violence using an epidemiologic approach with an Asian American and Pacific Islander (AAPI) adolescent sample (N = 881). The results were consistent with the increased popularity of MMA with 52% (adolescent males = 73%, adolescent females = 39%) enjoying watching MMA and 24% (adolescent males = 39%, adolescent females = 13%) practicing professional fight moves with friends. Although statistically significant ethnic differences were found for the two MMA items on a bivariate level, these findings were not statistically significant when considering other variables in the model. The bivariate results revealed a cluster of risk-protective factors. Regarding the multiple regression findings, although enjoying watching MMA remained associated with positive attitudes toward violence and practicing fight moves remained associated with negative out-group orientation, the MMA items were not associated with unique variances of youth violence perpetration and victimization. Implications included the need for further research that includes other diverse samples, more comprehensive and objective MMA and violence measures, and observational and intervention longitudinal studies.

Marcadores de lesão renal após treino de karate

Asian J Sports Med. 2012 Mar;3(1):41-6.

The effect of exercise on urinary gamma-glutamyltransferase and protein levels in elite female karate athletes.

Shavandi N, Samiei A, Afshar R, Saremi A, Sheikhhoseini R.

Department of Sports Physiology, Arak University, Arak, Iran.

PURPOSE: Post exercise proteinuria and increased urinary Gamma-Glutamyl transferase (GGT) levels can be indicative of exercise-induced renal damage. The aim of this investigation is to study the effect of one session of intensive training on renal damage markers and compare their values to those 6 hours after training.
METHODS: In this cross-sectional study with pre- and post-test design, 10 elite volunteer female athletes were selected and participated in one training session (2 hours). Urine samples were collected before training, one hour after training, and 6 hours after training. Urinary protein (Pr), creatinine (Cr), and GGT values were measured through laboratory methods and then Pr/Cr and GGT/Cr ratios were computed.
RESULTS: There were significant differences between values of protein, GGT and Creatinine in the three sampling phases (P<0.05). However, no significant differences were observed between values for GGT/Cr and Pr/Cr ratio. There were significant differences between the mean values of Creatinine, protein and GGT within pre-exercise and 1 hour post-exercise and within 1 hour post-exercise and 6 hours post-exercise (P<0.05).
CONCLUSION: It seems that a session of karate training does not result in renal damage and athletes can continue training after 6 hours.

segunda-feira, 26 de março de 2012

Contribuição energética no kata

Eur J Appl Physiol. 2012 Mar 23. [Epub ahead of print]

Energetics of basic Karate Kata.

Institut für Angewandte Trainingswissenschaft, Marschnerstrasse 29, 04109, Leipzig, Germany, bussweiler@iat.uni-leipzig.de.


Knowledge about energy requirements during exercises seems necessary to develop training concepts in combat sport Karate. It is a commonly held view that the anaerobic lactic energy metabolism plays a key role, but this assumption could not be confirmed so far. The metabolic cost and fractional energy supply of basic Karate Kata (Heian Nidan, Shotokan style) with duration of about 30 s were analyzed. Six male Karateka [mean ± SD (age 29 ± 8 years; height 177 ± 5 cm, body mass 75 ± 9 kg)] with different training experience (advanced athletes, experts, elite athletes) were examined while performing one time and two time continuously the sport-specific movements. During Kata performance oxygen uptake was measured with a portable spirometric device, blood lactate concentrations were examined before and after testing and fractional energy supply was calculated. The results have shown that on average 52 % of the energy supply for one Heian Nidan came from anaerobic alactic metabolism, 25 % from anaerobic lactic and 23 % from aerobic metabolism. For two sequentially executed Heian Nidan and thus nearly doubling the duration, the calculated percentages were 33, 25 and 42 %. Total energy demand for one Kata and two Kata was approximately 61 and 99 kJ, respectively. Despite measured blood lactate concentrations up to 8.1 mmol l(-1), which might suggest a dominance of lactic energy supply, a lactic fraction of only 17-31 % during these relatively short and intense sequences could be found. A heavy use of lactic energy metabolism had to be rejected.

quarta-feira, 21 de março de 2012

Nós, na Science; quem diria...

Um inglês bem mais ou menos, uma ideia razoavelmente antiga que sempre encontrou pouco apoio e alguém, de repente, a considera interessante...Gostei da surpresa : )

Curtam, pq outra matéria dessa deve demorar : )

Campeonato Sul-Americano de Kung Fu em Tatui

Divulgação da Juliana Lara:

sexta-feira, 2 de março de 2012

Função cognitiva de idosos após prática de karatê

Front Psychol. 2012;3:40. Epub 2012 Feb 20.

Effects of cognitive, motor, and karate training on cognitive functioning and emotional well-being of elderly people.

Department of Sport Science, Institute of Sport Science and Institute of Psychology, University of Regensburg Regensburg, Germany.


The present study investigated the influence of cognitive, motor, and Karate (accordingly the guidelines of the German-Karate-Federation, DKV) training on the cognitive functioning and mental state of older people between 67 and 93 years of age. The three training groups each consisted of 12 elderly participants; the waiting control group included 9 participants. Before the training, participants were evaluated with cognitive measurements (cognitive speed: number-connection test, number-symbol test; memory performance: digit-span test, blocking-tapping test, figure test) and a measurement of emotional well-being. After this pre-testing they participated the specific training in on average sixteen 1-h training sessions. The cognitive training exercised inductive thinking ability, the motor training worked on easy stretching and mobilization techniques, and the Karate training taught tasks of self-defense, partner training, and Katas. After completion of the training sessions, all tests were applied again. The results show no significant difference in cognitive improvement dependent on group between the three training conditions. However a significant improvement was found in the emotional mental state measurement for the Karate group compared to the waiting control group. This result suggests that the integrated involvement in Karate leads to a feeling of self-worth and that, even in elderly people, integration of new sports helps to improve quality of life.

Artigo sobre razão do torque isocinético, incluindo análise de judocas

J Sports Sci. 2012 Mar;30(6):547-53.

Isokinetic hamstrings-to-quadriceps peak torque ratio: The influence of sport modality, gender, and angular velocity.


a Departamento de Fisiologia , Universidade Federal de São Paulo (UNIFESP) , São Paulo , Brazil.


Abstract The purpose of this study was to determine differences in hamstrings-to-quadriceps (H/Q) peak torque ratios evaluated at different angular velocities between men and women who participate in judo, handball or soccer. A total of 166 athletes, including 58 judokas (26 females and 32 males), 39 handball players (22 females and 17 males), and 69 soccer players (17 females and 52 males), were evaluated using an isokinetic dynamometer. The H/Q isokinetic peak torque ratios were calculated at angular velocities of 1.05 rad · s(-1) and 5.23 rad · s(-1). In the analysis by gender, female soccer players produced lower H/Q peak torque ratios at 1.05 rad · s(-1) than males involved in the same sport. However, when H/Q peak torque ratio was assessed at 5.23 rad · s(-1), there were no significant differences between the sexes. In the analysis by sport, there were no differences among females at 1.05 rad · s(-1). In contrast, male soccer players had significantly higher H/Q peak torque ratios than judokas (66 ± 12% vs. 57 ± 14%, respectively). Female handball players produced significantly lower peak torque ratios at 5.23 rad · s(-1) than judokas or soccer players, whereas males presented no ratio differences among sports At 5.23 rad · s(-1). In the analysis by velocity, women's muscular ratios assessed at 1.05 rad · s(-1) were significantly lower than at 5.23 rad · s(-1) for all sports; among men, only judokas presented lower ratios at 1.05 rad · s(-1) than at 5.23 rad · s(-1). The present results suggest that sport modality and angular velocity influence the isokinetic strength profiles of men and women.

Nova opção de consulta e submissão; artigos indexados no pubmed

Asian J Sports Med. 2010 Mar;1(1):29-34.

Pre-participation Cardiovascular Screening of Elderly Wrestlers.

Sports Medicine Research Center, Tehran University of Medical Sciences, Tehran, IR Iran.



Sudden death of a competitive athlete is a tragedy that is usually caused by a previously unsuspected cardiovascular disease. The aim of this study was to clarify the role of noninvasive testing in pre-participation cardiovascular evaluation of elderly wrestlers.


We included 63 Iranian elderly wrestlers who participated in Tehran international elderly wrestlers' preparation camping by census method. A questionnaire including past medical and family history as well as coronary risk factors was filled out and then a complete physical examination of the cardiovascular system was done by an internist for all wrestlers. Electrocardiogram (ECG), complete echocardiographic examination and then symptom limited exercise test were performed and reported by the cardiologists who did not know the other examinations results.


Exertional dyspnea and typical chest pain (FC=I or II) were present in 5% and 1.7% of the examinees, respectively. There were one or more risk factors in 64.5% of the cases. Cardiovascular examination revealed abnormal heart sounds in 27.1%. ECG showed ischemic changes in 13.6% and premature atrial contractions and premature ventricular contractions in 11.4%. Echocardiography showed mild left ventricular systolic dysfunction in 3.4%, regional wall motion abnormality in 8.5%, valvular disease in 32.3%, diastolic dysfunction in 45.7%, and left ventricular hypertrophy in 16.9% of the cases. Exercise test results were negative, equivocal, positive and highly positive in 70.4%, 15.8%, 5.2%, and 8.6% of cases, respectively.


Beside physical examination, pre-participation screening of elderly wrestling athletes with ECG and exercise testing is feasible and recommended in the presence of coronary risk factors or cardiac symptoms. Echocardiography can also be recommended to detect other relevant abnormalities when there is a clue in the standard history, physical examination or ECG.

Asian J Sports Med. 2010 Mar;1(1):23-8.

Injury rates in Iranian taekwondo athletes; a prospective study.

Sports Medicine Research Center, Tehran University of Medical Sciences, IR Iran.



Taekwondo, as the most popular martial art among Iranian sportsmen, might lead to injury for the athletes of this sport during competitions. We decided to report the incidence rate of injuries sustained by the athletes of this sport during national competitions.


All competitions of Iran national championship taekwondo league in 2006-2007 with 204 athletes were observed prospectively to detect the occurrence of injuries. The severity of injuries was classified into four groups (mild, moderate, severe, and critical) according to the involvement of medical care team in the contest, ability of the athletes to resume and duration of probable absence of injured athletes from future competitions and training sessions. Athlete-Exposure (A-E) was defined as the number of competitions multiplied by two. On this base, the rate of injury incidence per 1000 A-Es, the rate of injuries per time unit and the rate of injury occurred for each 100 athletes were considered as the major outcomes of this study.


Of totally 1,338 A-Es, 93 injuries were recorded during the competitions. The rate of injury incidence was found to be 69.5 injuries per 1000 A-Es and the rate of injuries per minute of competitions was 0.023 which corresponded to 23.3 injuries per 1000 minutes of competitions. 45.6 injuries were occurred for each 100 athletes during the course of competitions. The most frequent injuries were mild (68.8%) and critical injuries (24.7%), followed by moderate and severe injuries; 4.3% and 2.1%, respectively.


The rate of injury we found was lower than that of western countries. In spite of finding the lower limbs as the most frequent place of injuries in other studies, we found the upper limbs as the most predisposed place of injuries which might be due to difference in the method of combat of Iranian athletes with other athletes.

Asian J Sports Med. 2010 Jun;1(2):117-21.

An addendum to injury rates in Iranian taekwondo athletes; a prospective study.


ExRA, Inc., Ann Arbor, MI, USA.



The objective of this study was to compare the Iranian taekwondo-in statistically in terms of total injury rates to international counterparts as gleaned from the extant literature.


The Iranian sample consisted of 204 male taekwondo-in participating in the national championship. The international sample included the participants in national and international tournaments. Validated standard questionnaires were employed at all tournaments to collect injury data that were always diagnosed by the respective tournament physicians. An injury was defined as any circumstance for which assistance was sought from the medical personnel. In addition to injury rates, 95% confidence intervals (CIs) around the rates were computed. To assess which group was at higher risk, odds ratios were calculated, including the 95%CIs.


Compared to Greek counterparts, the injury rate for the Iranian taekwondo-in was statistically significantly higher. The Iranians were also at a higher risk to incur an injury: OR = 11.2 (95%CI: 6.60-18.88, P<0.001, CLR = 2.86). When comparing the Iranian taekwondo-in to their colleagues competing at the 1999 World Championships, the former recorded a statistically significantly lower injury rate but the latter were not at a higher risk (OR = 0.61, 95%CI: 0.41-0.91, P=0.014, CLR = 2.20).


A statistical comparison of total injury rates in Iranian and international taekwondo-in revealed no difference between the two groups. However, what is of concern is that the total injury rate across taekwondo studies is significantly higher than those reported for American football.

Asian J Sports Med. 2011 Sep;2(3):205-10.

Investigating Two Different Training Time Frames during Ramadan Fasting.


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



Muslim athletes may continue training and competing while they are fasting. There is a concern about negative effects of fasting on sports performance. This study aimed to investigate the influence of two training time frames on athletes' body composition and performance during Ramadan fasting.


An observational study was conducted and thirty four male volunteer athletes from different sports including volleyball, karate, taekwondo and football were assigned in two groups. The first group included 14 elite athletes who during Ramadan voluntarily participated in training sessions at 1 hour before Iftar (BI) and the second group of 20 elite athletes who during Ramadan participated in training sessions at 3 hours after Iftar (AI). Testing was performed one week before; in the first and fourth weeks of Ramadan and one week after Ramadan. Weights, heights and skinfold thickness were assessed at each time point and body mass index was calculated. Each player was assessed for agility and explosive strength as well.


The mean weight and body mass index of both groups decreased significantly during Ramadan (P<0.001). Performance variables were not negatively affected by fasting in BI or AI group athletes.


Weight reduction might come with either BI or AI training schedules in Ramadan. Daytime or evening training did not inversely affect the agility and power performances in a group of elite athletes during Ramadan fasting.

Asian J Sports Med. 2011 Mar;2(1):31-6.

Martial arts: time needed for training.

Department of Physical Medicine & Rehabilitation, Emory University, School of Medicine, Atlanta, Georgia, USA.



To measure the time needed to teach a series of martial arts techniques to proficiency.


Fifteen volunteer subjects without any prior martial arts or self-defense experience were recruited. A panel of martial arts experts selected 21 different techniques including defensive stances, arm blocks, elbow strikes, palm strikes, thumbs to eyes, instep kicks and a carotid neck restraint. The critical elements of each technique were identified by the panel and incorporated into a teaching protocol, and then into a scoring system. Two black belt martial arts instructors directed a total of forty-five 45-minute training sessions. Videotaped proficiency testing was performed weekly. The videotapes were reviewed by the investigators to determine the proficiency levels of each subject for each technique.


The techniques were rated by the average number of training sessions needed for an individual to develop proficiency in that technique. The mean number of sessions necessary to train individuals to proficiency ranged from 27 to 38.3. Using this system, the most difficult techniques seemed to be elbow strikes to the rear, striking with thumbs to the eyes and arm blocking.


In this study 29 hours of training was necessary to train novice students to be proficient in 21 offensive and defensive martial arts techniques. To our knowledge, this is the first study that attempts to measure the learning curves involved when teaching martial arts techniques.

Efeito do grau de desidratação em respostas imunes após treino de judô de atletas do sexo feminino

Luminescence. 2012 Feb 24. doi: 10.1002/bio.2349. [Epub ahead of print]

Effects of dehydration on immune functions after a judo practice session.


Department of Social Medicine, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, 036-8562, Japan; Matsuyama University, 4-2 Bunkyo-cho, Matsuyama, 790-8587, Japan. nakaji@cc.hirosaki-u.ac.jp.


We investigated the effects of dehydration after a judo practice session on player muscle and immune functions. Subjects included 25 female university judoists. Investigations were performed before and after 2.5 h of regular judo practice. Body composition, serum enzymes (myogenic enzymes, immunoglobulins and complements), neutrophils counts, reactive oxygen species (ROS) production capability, and phagocytic activity (PA) were measured. Subjects were divided into two groups according to level of dehydration after practice (mild dehydration and severe dehydration groups) and results were compared. Creatine kinase was found to increase significantly after practice. In addition, neutrophil count also increased significantly after practice in both groups. The changing ratios of IgA, IgG and C3 observed in the mild dehydration group were significantly higher than those in the severe dehydration group. In the severe dehydration group, post-practice PA/neutrophil had decreased significantly. Significant positive correlations were found between severity of dehydration and changing ratios of IgA, IgG, IgM, C3, C4 and ROS production capabilities, whereas no significant association was seen with PA and/or serum SOD activity. These results suggest that dehydration resulted in immunosuppression, including decreased neutrophil function.