International Judo Research Articles

Effects of the Revision of the International Judo Federation Refereeing Rules on Competition Contents：Comparison of Grand Slam Paris 2016 and 2017

Effects of the Revision of the International Judo Federation Refereeing Rules on Competition Contents：Comparison of Grand Slam Paris 2016 and 2017

Prevalence, techniques and knowledge of rapid weight loss amongst adult british judo athletes: a questionnaire based study.

No investigation has analysed the RWL approaches since new rules by the International Judo Federation (IJF) regarding weigh-ins have been implemented in international competitions in 2014. The current study analyses the prevalence, most common methods and knowledge surrounding the effects of rapid weight loss (RWL) amongst adult UK judo athletes. Additionally, it examines differences in rapid weight loss behaviour (RWLB) between gender, weight-class, competitive level, age RWL began and "high"/"low" knowledge athletes. A previously validated questionnaire developed to assess RWL in judo athletes was modified by adding a knowledge section and revalidated for content. The questionnaire provided a RWLB score (higher score equated to more aggressive RWL) and a knowledge score (out of 10). 256 athletes (189 males and 66 females, aged 18-67 years) completed the questionnaire between February and April 2015. Unpaired t test, one-way ANOVA-tests and Chi-squared tests were used to test differences of mean RWLB scores and prevalence between groups. The prevalence of RWL was 84%. The most common methods of RWL were increased exercise and decreased food/fluid intake. The mean knowledge score was 6.2±2.8, with most incorrect answers regarding physiological effects of RWL. No significant differences in RWLB scores were found between gender, "high"/"low" knowledge athletes or weight-classes. Statistically significant differences in RWLB scores were found between different competitive levels (p=0.014) and age RWL began (p<0.01) in males but not in females. RWL is highly prevalent in the UK adult judo population and athletes have moderate knowledge surrounding its effects. In males, RWLB is most aggressive in elite level athletes and those that began RWL at a younger age. Therefore, updated rulings to target elite and youth level athletes should be implemented to reduce dangerous RWL. IV.

Political economy and judo: the globalization of a traditional Japanese sport

Since the late nineteenth century, the Japanese traditional sport of judo has been diffused throughout the world and established its position as a global sport. Through the process of globalization, judo has been changed and influenced by the transfer of power to organizations such as the International Olympics Committee and the International Judo Federation. This essay explores the contemporary issue of how the traditional Japanese sport of judo is misrepresented through its now institutionalized global governance and practice. A brief background on the modern history of Japanese sports, judo and the traditional Japanese values that were formerly abided by in the sport will be explained to then build a case towards its twentieth-century incorporation into the 1964 Tokyo Olympic Games. The global governance of the sport by the IJF is then criticized, particularly in terms of the change of the traditional rules and forms that have been installed under their power through economic, political and cultural amendments. Additionally, the impact of the globalization of judo in Japan is explained indepth. The conclusion of this essay is expected to identify further areas for research inquiry into the global governance of judo and how it is inseparable from the sportization process and that of the wider global political economy of neoliberal capitalism.

国際柔道連盟試合審判規定2014-2016が全日本柔道選手権大会の競技内容に及ぼす影響：ダイナミック柔道の観点から

国際柔道連盟試合審判規定2014-2016が全日本柔道選手権大会の競技内容に及ぼす影響：ダイナミック柔道の観点から

Regain in Body Mass After Weigh-In is Linked to Success in Real Life Judo Competition.

We examined the relationship between the regain of body mass (BM) after weigh-in and success in real-life judo competition. Eighty-six (36 females, 50 males) senior judoka volunteered for this observational study of an international judo competition. Subjects were weighed at the official weigh-in and one hour before their first competition fight (15-20 hr later). Regain in BM after weigh-in was compared between medal winners and nonmedalists, winners and losers of each fight, males and females and across weight divisions. Heavyweights were excluded from analysis. Prefight BM was greater than BM at official weigh-in for both males and females, with % BM gains of 2.3 ± 2.0 (p ≤ .0001; ES= 1.59; CI95% [1.63, 2.98]) and 3.1 ± 2.2 (p ≤ .0001; ES = 2.03; CI95% [2.30, 3.89]), respectively. No significant differences were found between weight divisions for post weigh-in BM regain. Differences in post weigh-in BM regain were significantly higher in medal winners than nonmedalists for males and females combined (1.4 ± 0.4% BM; p = .0026; ES= 0.69; CI95% [0.05, 2.34]) and for males alone (1.5 ± 0.6% BM; p = .017; ES= 0.74; CI95% [0.02, 2.64]), but not for females (1.2 ± 0.7% BM; p = .096; ES = 0.58; CI95% [-0.02, 2.31]). Differences in BM regain after weigh-in between winners and losers were significant across all fights (0.9 ± 0.3% BM; p = .0021; ES= 0.43; CI95% [0.31, 1.41]) but not for first round fights (0.8 ± 0.5% BM; p = .1386, ES = 0.38; CI95% [-0.26, 1.86]). Winners showed a greater regain in BM post weigh-in than losers. This may reflect the greater magnitude of the BM loss needed to achieve weigh-in targets which also relates to the experience level of successful athletes.

Salivary hormones and anxiety in winners and losers of an international judo competition

ABSTRACTThe purpose of this study was to investigate the responses of salivary hormones and salivary secretory immunoglobulin A (SIgA) and anxiety in winners and losers during an international judo competition. Twenty-three trained, male, national-level judo athletes provided three saliva samples during a competition day: morning, in anticipation of competition after an overnight fast, mid-competition, and post-competition within 15 min post-fight for determination of salivary cortisol, salivary testosterone, salivary testosterone/cortisol ratio, SIgA absolute concentrations, SIgA secretion rate and saliva flow rate. The competitive state anxiety inventory questionnaire was completed by the athletes (n = 12) after the first saliva collection for determination of somatic anxiety, cognitive anxiety and self-confidence. Winners were considered 1-3 ranking place (n = 12) and losers (n = 11) below third place in each weight category. Winners presented higher anticipatory salivary cortisol concentrations (p = 0.03) and a lower mid-competition salivary testosterone/cortisol ratio (p = 0.003) compared with losers with no differences for salivary testosterone. Winners tended to have higher SIgA secretion rates (p = 0.07) and higher saliva flow rates (p = 0.009) at mid-competition. Higher levels of cognitive anxiety (p = 0.02) were observed in the winners, without differences according to the outcome in somatic anxiety and self-confidence. The results suggest that winners experienced higher levels of physiological arousal and better psychological preparedness in the morning, and as the competition progressed, the winners were able to control their stress response better.

Fitness and Anthropometric Profiles of International vs. National Judo Medalists in Half-Heavyweight Category.

The aim of the study was to determine the anthropometric and fitness profiles of European half-heavyweight judokas by success in competition. For this purpose, we compared 5 international medalists (elite) with 5 national medalists (subelite). All male judokas won at least 1 medal in the half-heavyweight category during the previous 2 years. The testing in this cross-sectional study was performed during 4 days. All subjects underwent anthropometric assessment with body mass, height, skinfold, and limb circumference measures, and the body fat percentage was estimated by manual bioimpedance. The physical fitness evaluation consisted in peak torques for thigh and shoulder muscles, handgrip strength, high and long jumps, medicine ball throw, pull-ups, deadlift, bench press, deep squat, V[Combining Dot Above]O2max, Max Power, and Tokui Waza tests. The statistical analysis by the Student's t test showed significant differences for forearm and upper-arm circumferences, peak torques, pull-ups, bench press, deadlift, deep squat, V[Combining Dot Above]O2max, Max Power, and Tokui Waza tests. Our results showed that elite judokas have a superior fitness profile than subelite athletes from the half-heavyweight category. Moreover, elite judokas seem to have a higher arm muscle mass than subelite athletes but a similar body fat percentage. This study could be of interest for judo coaches with athletes competing in the half-heavyweight category, as some tests that discriminate by judo success for this specific weight category are described. Few studies analyze anthropometric and fitness profiles in half-heavyweight male judokas, so additionally our results can be used as a reference for coaches, athletes, and scientists.

Injuries Sustained During an International Judo Training Camp

Injuries Sustained During an International Judo Training Camp

Using a Daily Diary Approach to Understand the Psychological Experiences of Making Weight

Making weight refers to the process of reducing body weight to compete in weight-categorized sports. The current study explored judo athletes’ psychological experiences of making weight. Six international standard judo athletes participated for the length of time they required to make weight. An unstructured diary was used to collect data daily, supported by a follow-up interview. Data were analyzed using a holistic content analysis. Emergent themes included initiating the making weight process, competing demands of dual roles, temptation, impacts of restricted nutrition, and the desire for social support. Athlete stories provided rich descriptions of their experiences, revealing the extent to which difficulties were concealed and the process of making weight was normalized. Their accounts highlight the challenges associated with social support but the value of emotional disclosure. Future research should explore the potential uses of diaries as a form of disclosure.

Radio characterization for ISM 2.4 GHz Wireless Sensor Networks for judo monitoring applications.

In this work, the characterization of the radio channel for ISM 2.4GHz Wireless Sensor Networks (WSNs) for judo applications is presented. The environments where judo activity is held are usually complex indoor scenarios in terms of radiopropagation due to their morphology, the presence of humans and the electromagnetic interference generated by personal portable devices, wireless microphones and other wireless systems used by the media. For the assessment of the impact that the topology and the morphology of these environments have on electromagnetic propagation, an in-house developed 3D ray-launching software has been used in this study. Time domain results as well as estimations of received power level have been obtained for the complete volume of a training venue of a local judo club's facilities with a contest area with the dimensions specified by the International Judo Federation (IJF) for international competitions. The obtained simulation results have been compared with measurements, which have been carried out deploying ZigBee-compliant XBee Pro modules at presented scenario, using approved Judogis (jacket, trousers and belt). The analysis is completed with the inclusion of an in-house human body computational model. Such analysis has allowed the design and development of an in house application devoted to monitor the practice of judo, in order to aid referee activities, training routines and to enhance spectator experience.

Effects of the International Judo Federation Referee Rules on competition contents in the All-Japan Judo Championships: A 2008-2013 comparison

Effects of the International Judo Federation Referee Rules on competition contents in the All-Japan Judo Championships: A 2008-2013 comparison

Iniciação esportiva, tempo de prática e desenvolvimento de judocas olímpicos brasileiros

The objective of this study was to analyze the age of sports initiation, the initiation process in judo and practice time of Brazilian judo Olympic players. For this, we used a sample of 6 judokas belonging to the Brazilian team at the Olympic Games of Athens 2004. The research used an interview tool that consists in 2 open questions. The speeches indicated that early training is one of the most relevant factors for the acquisition of a high level of performance subsequent to the time that the average age of initiation into the sport occurred at around 6.2 ± 1.3 years. Family support combined with a microsystem development of athletes, form an environment capable of generating international level judo athletes.

Muscular strength profile in Tunisian male national judo team

it is well established that muscle strength is a determinant factor in judo. However, little data are available for African athletes. Therefore, the aim of this study was to provide reference data of the muscular strength profile (MSP) for an African team, Tunisian judo team. the study was conducted among ten international judo athletes from Tunisia. To determine their MSP, we used an isokinetic dynamometer to assess Hamstrings, Quadriceps of both knees and external, internal rotators of both shoulders. The angular velocities of the assessments were; 90, 180, 240°/s for the knees and 60, 120°/s for the shoulders. MSP was determined based on two parameters; the maximum peak torque (PT) of each muscle and the ratio agonistic/antagonistic muscles (R). The knee extensors and flexors in the "supporting leg" had higher PT than in the "attacking leg"; respectively, 245N.m versus 237 (p<0.05) and 147 N.m versus 145 (p>0.05). R was normal for both legs. Furthermore, both rotators of the dominant shoulder had higher PT; 84 N.m versus 71 for the internal rotators (p<0.05) and 34,7 N.m versus 29,0 for the lateral rotators (p<0.05). Inversely, R was higher in the non-dominant side; 45% versus 35, p<0.05). the MSP of the selected elites Tunisian judo athletes was characterized by 3 major features; a strength of the quadriceps in the standing leg significantly higher than in the attacking leg, a normal muscular balance Hamstrings/quadriceps in both legs and a strength of the shoulder' rotators higher in the dominant side.

Effects of the International Judo Federation Refereeing Rules on competition contents in the All-Japan Judo Championships: From the viewpoint of dynamic judo

Effects of the International Judo Federation Refereeing Rules on competition contents in the All-Japan Judo Championships: From the viewpoint of dynamic judo

European Judo Championships: impact of the new rule changes on points and penalties

In 2013 the International Judo Federation started to test new rules to judo competitions with the objective of make judo more attractive for the general public and to promote which has been denominated “positive judo”, i.e., a more combative style. The aim of the present investigation was to compare two consecutive European Judo Championships (2012 and 2013, i.e., before and after the rule changes, respectively) in terms of scores and penalties. Statistics involved chi-square, analysis for linear trends in proportions and odds-ratio (OR), using 5% as significance level. The rules changes resulted in the increase of penalties and in the decrease of waza-ari (males, χ2=8.76, P=0.003, OR=0.55; females, χ2=3.79, P=0.050, OR=0.61) and yuko (males, χ2=38.93, P<0.001, OR=0.31; females, χ2=6.84, P=0.009, OR=0.56) scores for both males and females, while increasing ippon only for males (χ2=5.03, P=0.025). The total number of shido also increased for both groups (males, χ2=14.21, P<0.001, OR=1.53; females, χ2=6.63, P=0.010, OR=1.43), while the prevalence of hansoku-make increased only for males (χ2=5.78, P=0.016, OR=8.43). Thus, the rules change did not achieve the goal established of increasing scores and decreasing penalties.

The transformation of technical-tactical behaviors for hand techniques used in attacking below the belt after the 2010 International Judo Federation rule revision

Background Due to a 2010 rule revision, attack with the arms or hands below the belt is prohibited, with the penalty being hansoku-make for the first offense. This strict rule must have affected competitors’ technical-tactical behaviors with regards to using hands and arms below the belt in contests. The purpose of the present study is transformation of technical-tactical behaviors for hand techniques attacking below the belt in men’s contests before and after the 2010 rule revision. Material & Methods: 436 men’s contests from the 2009 Grand Slam Tokyo and the 2010 Grand Slam Paris were examined. DVDs of the Federation of All Japan Judo were used. Five hand techniques used in below the belt maneuvers as referenced in the Kodokan manual were investigated. The analysts unanimously decided if the techniques performed by competitors could be categorized within one of the five hand techniques studied. Results: Use of kibisu-gaeshi significantly decreased (p<0.05). Use of sukui-nage used in countering an opponent’s crossguard grab significantly increased (p<0.05). Use of kata-guruma not utilizing below the belt hand or arm grabbing significantly increased (p<0.01). German, English, and Japanese contestants significantly decreased in their use of hand techniques below the belt (p<0.01, p <0.05, p<0.05, respectively). Conclusions: Sukui-nage was increasingly used to counter the opponent’s use of the cross-guard grab; the kata-guruma technique underwent a style transformation. On the other hand, kibisu-gaeshi could not be used effectively with the rule revision.

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.

Training needs of judo practitioners regarding sport psychology

Summary Introduction. Nowadays, cooperation of a sportsperson with a sport psychologist should be a standard practice, adopted already at the level of children and young people’s sport. Thus, what are the experiences of young people regarding cooperation with a sport psychologist? Do they know what such a specialist deals with? How do they imagine possible cooperation with him/her? The objective of the research was to diagnose the needs of sport practitioners in the area of sport psychology. The aim of the paper and the author’s research was to analyse the awareness of the place of psychology in sport of children and youth, as well as the need for mental training. Material and methods. The research covered 72 young Polish judo practitioners – 26 girls and 46 boys. The respondents were of various age and presented different levels of sport abilities. They were participants of international judo competitions for children and youth. Results. The majority of the respondents have not worked with a sport psychologist and do not know the scope of his or her professional competence. Moreover, almost ¾ of the respondents do not express the need for such cooperation. However, the analysis of selected areas in sport (especially differences in subjective experiences and behaviour at training and competitions) indicates that there are fields where urgent specialist intervention is required. Conclusions. The analysis of the results leads to the conclusion about the need to introduce preventive, educational and intervention measures, implemented simultaneously among children and young people practising sport, as well as among their coaches, parents and sport peer groups.

La proyección Kharbarelli: cómo y por qué funciona esta técnica

&lt;p class="MsoNormal" style="text-align: justify; margin: 0cm 0cm 6pt;"&gt;&lt;span style="mso-ansi-language: EN-US;" lang="EN-US"&gt;&lt;span style="font-size: small;"&gt;&lt;span style="font-family: Calibri;"&gt;The throwing technique that came to be known as the Kharbarelli Pick-up in the world of competitive judo is a good example of how different cultures and their unique grappling traditions have changed the look of this Olympic sport. This presentation of the Kharbarelli Pick-up illustrates and explains the theory, mechanics, and application of this unorthodox, effective and crowd-pleasing throwing technique. The author has an extensive background in sambo and judo and studied this technique for a number of years after seeing it used in international judo and sambo events. The Kharbarelli Pick-up, while considered “unorthodox” and not Japanese in origin, is effective because it exhibits the common elements of using an opponent’s balance and movement in the same way a “traditional” judo throw does.&lt;/span&gt;&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

The Relation of Body Fats, Anthropometric Factor and Physiological Functions of Iranian Female National Judo Team

Both the IJF (International Judo Federation) and the IOC (International Olympic Committee) regulations require athletes to compete in set weight categories. Competitors are matched by weight divisions, thus players demonstrate relatively low levels of body fat with a high strength to mass ratio, and therefore the purpose of this study was to investigate the relation of body fats, anthropometric factors and physiological functions of Iranian female national judo players. The participants of this study were eight players of Iranian Judo national team (age, 22.5± 2.4yr; weight, 66.01± 6.4kg; height, 165± 6.6cm). The physiological profile was composed of aerobic (maximal test) and anaerobic power (ergo amp test). For anthropometric and body composition profiles, height, weights, body fat percentage, body mass index (BMI), waist hip ratio (WHR) were measured. Correlations were found between weight and body fat percentage and WHR. However negative correlation was found between aerobic and anaerobic power. Also positive correlation was found between BMI and lean body mass. Finding has showed judo players in this study, were almost favorite in terms of aerobics power and weight. The judo players who presenting higher aerobic power present a better performance in high-intensity intermittent activities; judo players with larger circumferences present higher absolute maximal strength, but this relation was not significant when strength was expressed relative to body weight. While these variables do not necessarily predict performance in a sport where technique and tactics are essential elements for success, they may provide some goals for developing judo players.