Fabrício Boscolo Del Vecchio

Physiological profiles of elite judo athletes.

To be successful in international competitions, judo athletes must achieve an excellent level of physical fitness and physical condition during training. This article reviews the physiological profiles of elite judo athletes from different sex, age and weight categories. Body fat is generally low for these athletes, except for the heavyweight competitors. In general, elite judo athletes presented higher upper body anaerobic power and capacity than non-elite athletes. Lower body dynamic strength seems to provide a distinction between elite and recreational judo players, but not high-level judo players competing for a spot on national teams. Even maximal isometric strength is not a discriminant variable among judo players. However, more studies focusing on isometric strength endurance are warranted. Although aerobic power and capacity are considered relevant to judo performance, the available data do not present differences among judo athletes from different competitive levels. Typical maximal oxygen uptake values are around 50–55mL/kg/min for male and 40–45mL/kg/min for female judo athletes. As for other variables, heavyweight competitors presented lower aerobic power values. The typical differences commonly observed between males and females in the general population are also seen in judo athletes when analysing anaerobic power and capacity, aerobic power, and maximal strength and power. However, further research is needed concerning the differences among the seven weight categories in which judo athletes compete.

A comparison of time-motion performance between age groups in judo matches

Abstract The aim of this study was to compare time-motion indicators during judo matches performed by athletes from different age groups. The following age groups were analysed: Pre-Juvenile (13–14 years, n = 522), Juvenile (15–16 years, n = 353); Junior (19 years, n = 349) and Senior (>20 years, n = 587). The time-motion indicators included: Total Combat Time, Standing Combat Time, Displacement Without Contact, Gripping Time, Groundwork Combat Time and Pause Time. Analysis of variance (ANOVA) one-way and the Tukey test, as well as the Kruskal-Wallis test and Mann-Whitney (for non-parametric data), were conducted, using P < 0.05 as significance level. The results showed that all analysed groups obtained a median of 7 (first quantile - 3, third quantile - 12) sequences of combat/pause cycles. In total time of combat, the result was: for Total Combat Time, Standing Combat Time and Gripping Time: Pre-Juvenile and Senior were significantly longer than Juvenile and Junior. Considering Displacement Without Contact, Junior was significantly longer than all other age groups. For Groundwork Combat Time, Senior was significantly longer than all other age groups and Pre-Juvenile was longer than Junior. These results can be used to improve the physiological performance in intermittent practices, as well as technical-tactical training during judo sessions.

Injuries in judo: a systematic literature review including suggestions for prevention

Background There is limited knowledge on epidemiological injury data in judo. Objective To systematically review scientific literature on the frequency and characteristics of injuries in judo. Methods The available literature up to June 2013 was searched for prospective as well as retrospective studies on injuries in judo. Data extraction and presentation focused on the incidence rate, injury risk, types, location and causes of injuries. Results During the Olympic Games in 2008 and 2012, an average injury risk of about 11–12% has been observed. Sprains, strains and contusions, usually of the knee, shoulder and fingers, were the most frequently reported injuries, whereas being thrown was the most common injury mechanism. Severe injuries were quite rare and usually affected the brain and spine, whereas chronic injuries typically affected the finger joints, lower back and ears. The most common types of injuries in young judo athletes were contusions/abrasions, fractures and sprains/strains. Sex-differences data on judo injuries were mostly inconsistent. Some studies suggested a relationship between nutrition, hydration and/or weight cycling and judo injuries. Also, psychological factors may increase the risk of judo injuries. Conclusions The present review provides the latest knowledge on the frequency and characteristics of injuries in judo. Comprehensive knowledge about the risk of injury during sport activity and related risk factors represents an essential basis to develop effective strategies for injury prevention. Thus, the introduction of an ongoing injury surveillance system in judo is of utmost importance.

A Review of Time-Motion Analysis and Combat Development in Mixed Martial Arts Matches at Regional Level Tournaments

Mixed martial arts (MMA) have become a fast-growing worldwide expansion of martial arts competition, requiring high level of skill, physical conditioning, and strategy, and involving a synthesis of combat while standing or on the ground. This study quantified the effort-pause ratio (EP), and classified effort segments of stand-up or groundwork development to identify the number of actions performed per round in MMA matches. 52 MMA athletes participated in the study (M age = 24 yr., SD = 5; average experience in MMA = 5 yr., SD = 3). A one-way analysis of variance with repeated measurements was conducted to compare the type of action across the rounds. A chi-squared test was applied across the percentages to compare proportions of different events. Only one significant difference (p<.05) was observed among rounds: time in groundwork of low intensity was longer in the second compared to the third round. When the interval between rounds was not considered, the EP ratio (between high-intensity effort to low-intensity effort plus pauses) was 1:2 to 1:4. This ratio is between ratios typical for judo, wrestling, karate, and taekwondo and reflects the combination of ground and standup techniques. Most of the matches ended in the third round, involving high-intensity actions, predominantly executed during groundwork combat.

ACUTE EFFECTS AND POSTACTIVATION POTENTIATION IN THE SPECIAL JUDO FITNESS TEST

Miarka, B, Del Vecchio, FB, and Franchini, E. Acute effects and postactivation potentiation in the special judo fitness test. J Strength Cond Res 25(2): 427-431, 2011-The purpose of this study was to compare the acute short-term effects of (1) plyometric exercise, (2) combined strength and plyometric exercise (contrast), and (3) maximum strength performance in the Special Judo Fitness Test (SJFT). Eight male judo athletes (mean ± SD, age, 19 ± 1 years; body mass, 60.4 ± 5 kg; height, 168.3 ± 5.4 cm) took part in this study. Four different sessions were completed; each session had 1 type of intervention: (a) SJFT control, (b) plyometric exercises + SJFT, (c) maximum strength + SJFT, and (d) contrast + SJFT. The following variables were quantified: throws performed during series A, B, and C; total number of throws; heart rate immediately and 1 minute after the test; and test index. Significant differences were found in the number of throws during series A: the plyometric exercise (6.4 ± 0.5 throws) was superior (p < 0.05) to the control condition (5.6 ± 0.5 throws). Heart rate 1 minute after the SJFT was higher (p < 0.01) during the plyometric exercise (192 ± 8 bpm) than during the contrast exercise (184 ± 9 bpm). The contrast exercise (13.58 ± 0.72) resulted in better index values than the control (14.67 ± 1.30) and plyometric exercises (14.51 ± 0.54). Thus, this study suggests that contrast and plyometric exercises performed before the SJFT can result in improvements in the test index and anaerobic power of judo athletes, respectively.

Estudos em modalidades esportivas de combate: estado da arte

O objetivo do presente texto foi apresentar o estado da arte dos estudos sobre as modalidades esportivas de combate (MEC). Inicialmente, e destacada a relevância destas modalidades, tanto do ponto de vista historico, quanto em relacao a sua representatividade em competicoes internacionais, como os Jogos Olimpicos. Tambem sao apresentadas as areas mais comuns de atuacao do profissional de Esporte nas MEC, bem como as iniciativas de organizacao de eventos, publicacoes, grupos de estudos e instituicoes cientificas direcionadas as MEC. Posteriormente, estudos com possibilidade de aplicacao em diferentes areas de intervencao - preparacao fisica, tecnica e tatica, gestao e organizacao - por parte do profissional do Esporte foram destacados. Finalmente, perspectivas de novos estudos e aspectos relacionados a preparacao profissional sao evidenciados.

Rapid Weight Loss Elicits Harmful Biochemical and Hormonal Responses in Mixed Martial Arts Athletes

The purpose of this study was to compare biochemical and hormonal responses between mixed martial arts (MMA) competitors with minimal prefight weight loss and those undergoing rapid weight loss (RWL). Blood samples were taken from 17 MMA athletes (Mean± SD; age: 27.4 ±5.3yr; body mass: 76.2 ± 12.4kg; height: 1.71 ± 0.05m and training experience: 39.4 ± 25 months) before and after each match, according to the official events rules. The no rapid weight loss (NWL, n = 12) group weighed in on the day of the event (~30 min prior fight) and athletes declared not having used RWL strategies, while the RWL group (n = 5) weighed in 24 hr before the event and the athletes claimed to have lost 7.4 ± 1.1kg, approximately 10% of their body mass in the week preceding the event. Results showed significant (p < .05) increases following fights, regardless of group, in lactate, glucose, lactate dehydrogenase (LDH), creatinine, and cortisol for all athletes. With regard to group differences, NWL had significantly (p < .05) greater creatinine levels (Mean± SD; pre to post) (NWL= 101.6 ± 15-142.3 ± 22.9μmol/L and RWL= 68.9 ± 10.6-79.5 ± 15.9μmol/L), while RWL had higher LDH (median [interquartile range]; pre to post) (NWL= 211.5[183-236] to 231[203-258]U/L and RWL= 390[370.5-443.5] to 488[463.5-540.5]U/L) and AST (NWL= 30[22-37] to 32[22-41]U/L and 39[32.5-76.5] to 72[38.5-112.5] U/L) values (NWL versus RWL, p < .05). Post hoc analysis showed that AST significantly increased in only the RWL group, while creatinine increased in only the NWL group. The practice of rapid weight loss showed a negative impact on energy availability and increased both muscle damage markers and catabolic expression in MMA fighters.

Development and validation of a time-motion judo combat model based on the Markovian Processes

The aim of the study was to develop a technical-tactical model of judo combat. Thus, 2.316 combats performed by men ranked as the world’s best and qualified for the 2012 Olympics Games were collected in 2011 and 2012, and 769 performances were used and 53.403 combat situations were analyzed. In order to develop the model of combat situations and the combinations between phases, as well as their respective components, the statistical analysis used the multi-state Markov Model. Moreover, the objectivity of the analysis was observed with comparisons and, the intra and inter-agreement was verified by means of the Cohen Kappa coefficient. Results showed no differences among analysts and referent to the actions in each phase of combat, the correlations analyses showed a “Almost perfect” classification for 87% of all variables analyzed. Regarding Markovian process analysis of the combat phases, results show the main tactical systems of attacks, where attack to the front follows attack to the right in the most part of the time and the highest likelihood to occur a projection is after attack to the front and to the right orientations. This information can help analysts and coaches to improve tactical and physiological athlete’s performance.

Isokinetic Dynamometry and 1RM Tests Produce Conflicting Results for Assessing Alterations in Muscle Strength

Abstract The purpose of this study was to compare strength gains in the lower limbs, assessed by one maximum repetition (1RM) and isokinetic peak torque (PT), in young men undergoing a resistance training (RT) program. Twenty-seven young men performed resistance training twice a week for 11 weeks. Training involved two exercises for the lower body, two for the upper body and one for the midsection performed with three sets of 8-12 repetitions to momentary muscle failure. Before and after the training period, participants performed the 1RM test in the 45° leg press and knee extension PT in isokinetic dynamometry. The Pearson correlation coefficient was used to assess the relationship between the changes in 1RM and PT, and the Bland-Altman test was performed to check for agreement between the strength changes of both tests. There were significant changes in 1RM and PT of 23.98% and 15.96%, respectively (p < 0.05). The changes in leg press 1RM were significantly higher than the ones in PT. The Bland-Altman analysis revealed that the tests were not equivalent. In conclusion, professionals and researchers involved in strength assessment should be aware that the results obtained by PT and 1RM are not equivalent when evaluating individual responsiveness and/or the efficacy of an intervention on muscle strength, as the results obtained show large variations and can be even conflicting.

Comparisons of Time-motion Analysis of Mixed Martial Arts Rounds by Weight Divisions

This study aimed to compare time-motion analysis between weight divisions in male fighters and rounds of Mixed Martial Arts (MMA). The sample consisted of 2097 bouts separated by weight divisions (Flyweight n=114, Bantamweight n=224, Featherweight n=286, Lightweight n=450, Welterweight n=390, Middleweight n=316, Light heavyweight n=167, Heavyweight n=150) of 2012-2014 UFC™ events. The time-motion variables were categorized into low or high-intensity, stand-up or groundwork situations by round. Effects of weight divisions were observed and the main results showed that, in the 1st round, the heavyweights (212.4±101.5s) presented with a shorter effort time than all other weight divisions (257.6±79.9s); in the 2nd round, the bantamweight competitors (132.8±90.9s) presented with the shortest total effort time (171.7±81.5s); in the 3rd round, the shortest total effort time was in the heavyweight division (246.3±89.1s) again, with the other weight divisions showing variable effort times, including: welterweight (289.6±42.3s), lightweight (280.3±57.3s), featherweight (281.4±58s), bantamweight (285.6±47.2s), flyweight (287.7±43.8s) and middleweight (268.3±72.2s). The present data suggest a focus on the intermittent demands presented in the various combat phases in MMA. Additionally, strength and conditioning coaches should pay particular attention to the high and low effort ratios for both standing and ground combat to most effectively condition their athletes.