Exploring characteristics of and transitions between mental states within the Multi-Action Plan model in high-level judo.

The Multi-Action Plan (MAP) model presents an idiosyncratic framework for human performance. MAP research has categorised four Performance Types (PTs; T1-T4) using self-paced activities. Specifically, T1-4 present four distinct mental states experienced by athletes during performance, differing, among other aspects, in the level of effort and perceived control. However, transitions between PTs are yet to be empirically investigated. This study aimed to examine MAP in the hyperdynamic open-skill combat context of judo. We explored how judoka experienced PTs and the transition processes between these mental states. Six British, high-level judoka (n = 6; Mdnage = 19) were interviewed using a retrospective semi-structured interview schedule. Interpretative phenomenological analysis indicated that judo presents a hyperdynamic difficult-to-predict performance context due to the opponent and fighting rhythm. Second, participants strongly related to T2 and T3 and less to T1 and T4. They also reported experiences 'between' T2 and T3. Lastly, participants reported common transition pathways (e.g., T2-T3), typical transition cues, and specific trainable strategies to optimise performance. Findings are discussed in relation to existing literature. Lastly, we present limitations, applied, and research considerations.

Impact of repeated sportive chokes on carotid intima media thickness and brain injury biomarkers in grappling athletes.

PURPOSE: Vascular neck compression techniques, referred to as 'chokes' in combat sports, reduce cerebral perfusion, causing loss of consciousness or voluntary submission by the choked athlete. Despite these chokes happening millions of times yearly around the world, there is scant research on their long-term effects. This pilot study evaluated whether repeated choking in submission grappling impacts the carotid intima media thickness (CIMT) and brain injury biomarkers (NFL, hGFAP, t-Tau, and UCH-L1). METHODS: Participants (n = 39, 29 male; ages 27-60 years) were assigned to one of two study arms: Grapplers (n = 20, 15 male) and 19 age/sex/body size matched controls. Grapplers had been exposed to >500 choke events while training for >5 years in a choke-inclusive sport. Exclusion criteria were recent TBI or deficits from a past TBI or stroke. Bilateral ultrasound measurement of the CIMT was performed, and blood was collected for quantitative analysis of four brain injury markers. Subgroup analyses were performed within the Grappler group to account for blunt head trauma as a possible confounder. RESULTS: There was no overall difference in CIMT measurements between Grapplers (mean 0.55 mm, SD 0.07) and Controls (mean 0.57 mm, SD 0.10) p = 0.498 [95% CI -0.04-0.08], nor were there CIMT differences between Grappler subgroups of blunt Trauma and No-Trauma. There were no significant differences in any biomarkers comparing Grapplers and Controls or comparing Grappler subgroups of Trauma and No-Trauma. CONCLUSION: This study found no significant difference in CIMT and serum brain injury biomarkers between controls and grapplers with extensive transient choke experience, nor between grapplers with extensive past blunt head trauma and those without.

Efficacy of Health Surveillance and Polymerase Chain Reaction Testing in Judo During the COVID-19 Pandemic.

Background The COVID-19 pandemic necessitated infection control for all sporting activities. More careful infection control measures are required in judo, where close contact with opponents cannot be avoided. The Medical Science Committee of the All Japan Judo Federation (AJJF) established infection control guidelines for daily practice and competitions. Infection control measures were also implemented at the national tournament organized by the AJJF. Objective and methods This study aimed to examine the effectiveness of pre-tournament health surveys and PCR testing in guidelines for judo tournaments. Participants had to complete a health survey one to two weeks before the tournament. Initially, PCR testing was performed on all athletes; however, the final policy was to conduct PCR testing only on athletes with an infected person (risk team testing method). The effectiveness of these methods was also examined. Results In 16 competitions between October 2020 and March 2023, 6980 contestants were registered, and PCR testing was performed on 3672 athletes; 29 (0.79%) had a positive PCR test. Only two contestants were unable to attend the tournament because of the health survey. No competition-related cluster outbreaks were observed. From May 2022, the competition was held under the guideline that only teams at risk of infection were tested and could only compete when they tested negative. No teams were tested according to this guideline. In the competitions organized within this guideline, only one person could not compete because of the information provided in the health survey. No clusters were observed in any of the competitions. The incidence of COVID-19 infection in the first week after the convention was 20 (0.60%) in testing only at-risk teams and 21 (0.57%) in testing all competitors, which was not significantly different.(p=0.62) Conclusion During the COVID-19 epidemic, health surveillance was necessary to prevent the registration of competitors at risk of infection prior to tournaments. If teams at risk of infection could be identified, PCR testing of all athletes might not be mandatory, and competitions could be organized safely. The Judo infectious disease control guidelines we have developed might be used for other contact sports in the future when other infectious diseases are prevalent.

Direct contact and very rapid valgus distortion characterise the injury mechanism of anterior cruciate ligament ruptures in judo.

PURPOSE: To analyse anterior cruciate ligament (ACL) rupture (ACLR) injury mechanisms in competitive judo using systematic video analysis, focusing on contact situations and biomechanics. METHODS: Seventeen videos of judo competitions wherein athletes developed ACLRs were included and retrospectively evaluated by five analysts. In all videos, the moment of initial contact and the index frame were defined. The judo techniques leading to the injury; the occurrence of direct contact, indirect contact or noncontact mechanisms; the time interval between the initial contact and index frame; the positions of the hip, knee and foot in relation to the initial contact and index frame; and the balance status during the initial contact and index frame were recorded. RESULTS: Eleven (65%) of ACLRs in judo involved direct contact. The mean time interval between initial contact and index frame was 15 ± 22 ms. Thirteen (77%) athletes were not balanced at initial contact. In the index frame, the hip was abducted in all cases and in combination with internal rotation in 12 (71%) cases. From initial contact to index frame, hip flexion increased in all cases; at index frame, the knee joint was internally rotated relative to the trunk in 12 (71%) cases, and the knee flexion angles increased from the initial contact. In the index frame, the foot was externally rotated relative to the knee in 12 (71%) cases, and severe valgus development of the knee with valgus collapse was observed in 14 (82%) cases. CONCLUSIONS: A direct attack on the knee was the most common injury mechanism observed. Valgus distortion appears to be the most important component of the mechanism of injury. With this knowledge, 'modified defence reactions' for specific judo techniques can be developed to reduce the injury risk. LEVEL OF EVIDENCE: Level IV.

A Case Report of a National Judo Champion: Is Return to High-Level Contact Sports Possible After Meniscus Allograft Transplantation?

Meniscus allograft transplantation (MAT) is a surgical procedure reserved for (relatively) younger individuals who remain symptomatic after the resection of a voluminous part of the meniscus. Return to sports and certainly the level of sport post-MAT are highly variable. We present a unique case of a national judo champion who was able to compete at the highest level following MAT. Considerations regarding the rehabilitation and follow-up of this patient are provided, and the risk of rerupture is discussed. Although returning to high-level contact sports post-MAT is possible, the risk of rerupture should be considered.

Judo for older adults: the coaches' knowledge and needs of education.

This study aimed to explore the views of judo coaches on their perceived knowledge (PK) and needs for education (NE) for training older practitioners. In total, 470 international (Europe = 48%, Americas = 22%, Africa = 23%, Asia = 5% and Oceania = 2%) judo coaches (IJF: level 1 = 55,3%, level 2 = 33%; judo black belt: 3,4 ± 1,7 dan; F = 15%; university education: 68% >BA) responded an online survey encompassing demographic information and 35 items relevant to training older adults (Aging process; Safety and First Aid; Organization & Environment; Physiology and Fitness; Psychology & Mental Health; Teaching & Training) to be rated on a 7-point Likert scale for PK and NE. Non parametric statistics (p > 0.05) was applied to ascertain differences and relationships between PK and NE, respectively. A bivariate go-zone plot was used to highlight items with the lowest PK and the highest NE mean values. The coaches reported high PK (4.5 ± 0.3 pt) and NE (4.7 ± 0.1 pt) values, with significant higher PK values emerging for high education levels and judo experience. In considering their unique needs and special role, the judo coaches presented valuable insights to develop a sustainable educational curriculum tailored to train older judo practitioners.

Does Grappling Combat Sports Experience Influence Exercise Tolerance of Handgrip Muscles in the Severe-Intensity Domain?

Successful performance in grappling combat sports (GCS) can be influenced by the fighter's capacity to sustain high-intensity contractions of the handgrip muscles during combat. This study investigated the influence of GCS experience on the critical torque (CT), impulse above CT (W'), tolerance, and neuromuscular fatigue development during severe-intensity handgrip exercise by comparing fighters and untrained individuals. Eleven GCS fighters and twelve untrained individuals participated in three experimental sessions for handgrip muscles: (1) familiarization with the experimental procedures and strength assessment; (2) an all-out test to determine CT and W'; and (3) intermittent exercise performed in the severe-intensity domain (CT + 15%) until task failure. No significant differences were found in CT and neuromuscular fatigue between groups (p > 0.05). However, GCS fighters showed greater W' (GCS fighters 2238.8 ± 581.2 N·m·s vs. untrained 1670.4 ± 680.6 N·m·s, p < 0.05) and exercise tolerance (GCS fighters 8.38 ± 2.93 min vs. untrained 5.36 ± 1.42 min, p < 0.05) than untrained individuals. These results suggest that long-term GCS sports training can promote increased tolerance to severe-intensity handgrip exercise and improved W' without changes in CT or the magnitude of neuromuscular fatigue.

A Judo-Based Exercise Program to Reduce Falls and Frailty Risk in Community-Dwelling Older Adults: A Feasibility Study.

OBJECTIVES: This study aimed to explore the feasibility (including recruitment, safety and adherence) and the effects of a twice weekly supervised Judo-based exercise program over eight weeks on mobility, balance, physical performance, quality of life, fear of falling and physical activity (including by frailty status) in community-dwelling older people aged ≥65 years. DESIGN: Pre-post study. PARTICIPANTS: A total of 17 participants (mean age 74.3±6.2; range 66-87 years; 76.5% female). INTERVENTION: A Judo-based exercise program conducted twice weekly for 60 minutes per session over eight weeks. MEASUREMENTS: Pre and post assessments included the Timed Up and Go (TUG); the Berg Balance Scale (BBS); the Short Physical Performance Battery (SPPB); the Short Form Health Survey-36 (SF-36); the Falls Efficiency Scale International (FES-I); and an ActivPal accelerometer to measure participants' physical activity. RESULTS: Most participants had low (≤3) Charlson's Comorbidity Index scores (n=17, 100%), were well nourished (n=16, 94.1%), not sarcopenic (n=16, 94.1%), and not cognitively impaired (n=13, 76.5%), anxious or depressed (n=14, 82.4%). Ten participants (58.8%) were non-frail and seven were pre-frail (41.2%). Significant improvements (p<0.05) were seen for mobility (TUG), balance (BBS) and physical performance (SPPB). Pre-frail participants showed greater improvement in mobility (TUG) than non-frail participants (p=0.020). No changes (p≥0.05) were seen in quality of life, fear of falling, or physical activity. Participants' adherence (i.e., attending sessions) was high (i.e., ≥81.2%). No serious adverse events or withdrawals were reported. CONCLUSION: Findings suggest that the eight week Judo-based exercise program can be delivered safely to older adults aged ≥65 years, including those at-risk of frailty, as long as there is close supervision with individualisation of the program in response to emergent health symptoms and the program is conducted on requisite Judo mats. This Judo-based exercise program is effective in improving physical function with potential to prevent falls and frailty risk.

Variability Analysis in Judo Para Athletes With Visual Impairments: Match-Outcome Performance in the Tokyo 2020 Paralympic Games With Evidence From the New Classification System.

Match-related performance analysis in judo Para athletes with visual impairments is important to coaches and staff to identify technical-tactical profiles of their athletes and opponents but also to identify whether there are similar characteristics in each visual class. Thus, this study explores the match-related performance in judo Para athletes and verifies the relationship between performance using the old and new classification systems. The match-derived variables were analyzed using different statistical methods considering a total of 182 matches from the Tokyo 2020 Paralympic Games. The results indicated that performance was affected by sex and degree of impairment. The new classification system seems suitable for grouping Para judo athletes, as it differentiates performance between the two proposed classes (J1 and J2), since athletes from each group compete separately. Furthermore, different variability index measures were correlated with competitive performance, demonstrating a specific performance profile for each sport class in judo.

Lateral preference in complex combat situations: Prevalence and relationship with general measures of hand and foot preference.

Laterality is considered relevant to performance in combat sports with particular emphasis being placed on fighters' handedness and combat stance. Such approach, however, may fall too short to understand the role of laterality in sports where fighters are allowed to use their hands and feet standing and on the ground. Here, we referred to grappling sports (i) to estimate lateral preferences in selected combat situations and (ii) to test for an association between those preferences and common measures of hand and foot preference. Based on the responses of 135 experienced grapplers who participated in an online questionnaire lateral preference, at the group-level, was revealed in 12 out of 18 combat situations. At an item-level, common measures of lateral preference and grappling-specific lateral preference were related in three out of 36 conditions (footedness only, not handedness). Across items, scores in a grappling-specific laterality index were positively related with foot but not with hand preference scores. Implications for the assessment of lateral preference in combat sports and the use of item-specific terminology in this context are discussed. On a broader scale, we also elaborate on potential consequences of our findings with regard to evolutionary explanations of the maintenance of left-handedness in humans.

Effects of extracurricular martial arts practice on the trait of anger among boys and girls aged 9-12 years old / Efectos de la práctica de artes marciales en el ámbito extraescolar sobre el rasgo de ira de niños y niñas entre 9 y 12 años

Nowadays, aggression in children is an alarming problem and there are more and more programs carried out with students in order to reduce violence and aggressive behaviour. Martial arts have been used, on occasions, in these programs due to the values of respect and self-control that give it. However, they have not always obtained the expected results. The purpose of this paper is to observe is martial arts like judo and karate are a successful method to decrease anger levels in children. To evaluate this, a quasi-experimental longitudinal study during a period of 6 months in which 82 children took part, divided in a control group and an experimental group (karate and judo). State-Trait Anger Expression Inventory for Children and Adolescents (STAXI-NA) was used. Meaningful differences were found only in some of the anger components, between anger-in expression pre-tests of the control and experimental group and between anger-out expression pre-tests and post-tests of the karate group. The results obtained in this study suggest that the martial arts training has no effect about global anger management in children students. Common aspects are pointed out in interventions that have decreased the levels of anger (traditional aspects, design of a specific program, subjects with behavior problems, school context) and it is shown with the results obtained, how a habitual intervention carried out in a context of sports clubs, in a normal population and without a specific program, have difficulties in reducing the anger of the participants (AU)

Hoy en día la agresión en los/as niños/as es un problema preocupante, donde se ha utilizado en algunos programas, las artes marciales para disminuir los niveles de violencia, debido a los valores de respeto y autocontrol que se le otorgan. Sin embargo, no siempre se ha obtenido los resultados esperados. El objetivo de este artículo es observar si las artes marciales, como el judo y el karate, son un método adecuado para disminuir los niveles de ira en los/as niños/as. Se realizó un estudio longitudinal cuasi-experimental durante un período de seis meses en el que participaron 82 niños/as, divididos en grupo control y experimental (kárate y judo). Fue utilizado el Inventario de Expresión de Ira Estado-Rasgo para Niños y Adolescentes (STAXI-NA). Se encontraron diferencias significativas sólo en algunos de los componentes de ira, en las pruebas previas de expresión de ira del grupo control y experimental, y en las pruebas previas y posteriores de expresión de ira del grupo de karate. Los resultados obtenidos en este estudio sugieren que el entrenamiento en artes marciales no tiene efecto sobre la gestión global de la ira en niños/as. Se señalan aspectos comunes en las intervenciones que han disminuido los niveles de ira (aspectos tradicionales, diseño de un programa específico, sujetos con problemas de conducta, contexto escolar) y se muestra con los resultados obtenidos, cómo una intervención habitual realizada en un contexto de club deportivo, en una población normal y sin un programa específico, tienen dificultades para reducir la ira de los participantes (AU)

Should Blind Judokas and Partially Sighted Judokas Compete Together? A Reflection from the Study of the Temporal Structure of Combat.

The investigation of the temporal structure of Para judo combat according to sport classes or visual categories (B1, B2 and B3) has only been carried out in women. The objectives of the study were to analyze the differences in the temporal structure of combat between the male para-judokas sport classes, and to determine whether blind judokas and partially sighted judokas should compete together. All para-judokas who competed in the 2018 IBSA Judo World Championships (172 men) participated in the study. Using observational methodology, we analyzed all the combats (n = 232). To obtain the results, we used different analysis techniques: descriptive, one-way ANOVA, t-test for independent samples and effect size. The level of significance established for the study was ρ ≤ 0.05. The results indicate that during pauses, time dedicated to displacement was increased when there was a B1 judoka in the pairing, causing pauses to be significantly longer. Coaches should take this into account. In conclusion, there are differences between particular visual categories. B1 judokas have longer pauses, perform more ground fighting sequences and win fewer combats. The competition is not on equal terms. More research is needed in order to determine if new regulations have modified the combat temporality.

Transitioning from junior to senior: a case study on elite judokas in South Korea.

Introduction: This study explores the experiences of Korean elite judokas during their junior to senior transition (JST), including both male and female participants, to provide empirical evidence for the development of tailored support services or programs for this target population. Methods: We recruited 12 elite judokas for our study, comprising eight males and four females, all in their first year of university. Given their preferences and availability at the time of data collection, participants were divided into three focus groups: Focus Group 1 (FG1; four male participants), Focus Group 2 (FG2; four female participants), and Focus Group 3 (FG3; four male participants). Thematic analysis was applied to analyze the data from the focus group interviews. Results: Five main themes were identified: (a) COVID-19-Induced Frustration, (b) From Big Fish in a Small Pond to Small Fish in a Big Pond, (c) Challenges in Academic Commitment, (d) Adapting to Transitions in Living Arrangements, and (e) Recognizing Support Needs for the JST. Discussion: The findings of this study provide both theoretical and practical implications that could improve judokas' experiences during the challenging physical and mental phase of JST, as well as inform the establishment of tailored support programs and schemes for successful and smooth JSTs for athletes.

Brain structural correlates of psychopathic traits in elite female combat-sports athletes.

Psychopathy is characterized by glibness and superficial charm, as well as a lack of empathy, guilt and remorse, and is often accompanied by antisocial behaviour. The cerebral bases of this syndrome have been mostly studied in violent subjects or those with a criminal history. However, the antisocial component of psychopathy is not central to its conceptualization, and in fact, psychopathic traits are present in well-adjusted, non-criminal individuals within the general population. Interestingly, certain psychopathy characteristics appear to be particularly pronounced in some groups or professions. Importantly, as these so-called adaptive or successful psychopaths do not show antisocial tendencies or have significant psychiatric comorbidities, they may represent an ideal population to study this trait. Here, we investigated such a group, specifically elite female judo athletes, and compared them with matched non-athletes. Participants completed psychopathy, anger, perspective-taking and empathic concern questionnaires and underwent structural magnetic resonance imaging (MRI). Grey matter volume (GMV) was computed using voxel-based morphometry from the T1-weighted images. Athletes scored significantly higher in primary psychopathy and anger and lower in empathy and perspective taking. They also exhibited smaller GMV in the right temporal pole, left occipital cortex and left amygdala/hippocampus. GMV values for the latter cluster significantly correlated with primary psychopathy scores across both groups. These results confirm and extend previous findings to a little-studied population and provide support for the conceptualization of psychopathy as a dimensional personality trait which not only is not necessarily associated with antisocial behaviour but may potentially have adaptive value.

Analysis of grip specificity on force production in grapplers and its effect on bilateral deficit grip specificity and bilateral deficit in force production among grapplers.

The use of strength training is important for athletes in combat sports such as judo and jiu-jitsu. Specificity is key when prescribing strength training programs for athletes, considering maximal strength, muscular power and strength-endurance. Grappling combat sports require grip control, which is necessary to execute throwing techniques and groundwork. The aim of this study was to verify the bilateral strength deficit in general and in grappling combat sport-specific action in the control group and grapplers. A sample of 73 subjects, divided into 2 groups, was used: the Student Group (15 females and 16 males) and the Grappler Group (29 males and 13 females). The male and female participants attended four laboratory sessions over a 48-hour interval, the first two to familiarize themselves with the Electromechanical Functional Dynamometer (EMFD), and the last two to collect maximal isometric strength data, using a standard grip and a judo/jiujitsu specific grip. Significant differences in mean and peak forces (p < 0.001) were found, with high performance combat sport athletes having greater maximal isometric strength compared to students both bilaterally and unilaterally (p < 0.001). All comparisons also indicated higher values for males compared to females (p < 0.001). The results suggest that specific training in combat sports as well as sex differences play a significant role in maximal isometric strength performance. The type of grip used affects the application of force in the upper limb isometric strength tests, finding a main effect of grip type (p < 0.001), with the standard grip obtaining higher levels. However, the dominance between hands remains constant. More research is needed on specific judogi/jiu-jitsu-gi grips and their impact on maximal isometric strength with the EMFD.

Fighting for Olympic dreams and life beyond: Olympian judokas on striving for glory and tackling post-athletic challenges.

Objectives: This study explores the experiences of Olympian judokas, examining both their pursuit of excellence to compete at the Olympics and their subsequent transition out of judo. The aim is to offer empirical evidence regarding the challenges they face in realizing their Olympic dreams, and to shed light on the transitional challenges, available resources, and needs they face as they move toward post-athletic lives. Methods: We conducted semi-structured interviews with eight Olympian judokas: five males and three females, all of whom have retired from competitive judo. These participants are from Portugal (n = 1), Republic of Korea (n = 2), and the United Kingdom (n = 5). We employed thematic analysis, which led to the identification of five main themes: (a) From Dreams to Olympic Reality, (b) Facing the Void: Loss of Goals and Identity, (c) The Crucial Role of Social Support, (d) Dual Aspects of Pre-Retirement Planning, and (e) The Double Edge of Organizational Support. Findings: The findings highlight the significant challenges faced by Olympian judokas, including goal and identity loss post-retirement, and the need for comprehensive and accessible organizational support, particularly psychological assistance, to assist in their transition to post-athletic life. Implications: The findings not only enhance our understanding of judokas' experiences during transition but also offer insights that could guide the development of tailored support programs. It is critical for sport governing bodies and practitioners to apply these insights in creating comprehensive and easily accessible support systems, which will ensure a smoother transition to post-athletic life for high-performance athletes.

Oxidative status alteration during aerobic-dominant mixed and anaerobic-dominant mixed effort in judokas.

This study aimed to depict the oxidative status variation in judokas during aerobic-dominant mixed effort (AeDME) and anaerobic-dominant mixed effort (AnDME). It is to be expected that the sporting commitment of Judo is a stimulus of oxidative stress leading to the recruitment of antioxidant responses. Blood samples were collected from 17 athletes at rest, immediately after a training session (AeDME) and after a 5-min bout (AnDME). AeDME and AnDME caused significant increases in malondialdehyde (MDA) (p < 0.01 and p < 0.001 respectively) and glutathione (GSH) (p = 0.018 and p < 0.001 respectively). Blood thiol concentrations decreased following AeDME and AnDME (p < 0.001) whilst catalase decreased significantly after AnDME (p = 0.026) only. Uric acid increased significantly after AnDME than after AeDME (p = 0.047) while, conversely, total bilirubin was higher after AnDME than after AeDME (p = 0.02). We may ultimately summarize that AeDME and AnDME caused oxidative stress, higher in AnDME, and some antioxidant response slightly higher in AnDME compared to AeDME. In sports, monitoring of oxidative stress status is recommended as part of the training regimen.

Influence of Practice Periodization and Sleep Duration on Oxidative Stress in High School Judo Athletes.

Numerous research studies have investigated the relationship between exercise, oxidative stress level, and condition in athletes who engage in intense training on a daily basis. However, it is known that oxidative stress is affected by exercise, sleep, and the psychological state, but there are only a few studies that have comprehensively examined oxidative stress based on the actual practice periods and living conditions of athletes. Therefore, our study aimed to explore the influence of three distinct training periods (short training period, intensive training period, and pre-competition periods) as well as life situations (sleep and number of steps) on oxidative stress levels (diacron reactive oxygen metabolites: d-ROMs) in high school judo athletes. The results showed that, among the three periods, the level of oxidative stress increased the most during the pre-competition period, and the value was higher than during the training period, when the intensity of training was highest. The levels of the d-ROMs values during the pre-competition period were negatively correlated with the amount of sleep on the previous day. The findings suggest that, besides the exercise intensity, factors such as sleep duration and other life situations should be regarded as critical considerations for high school judo athletes.

Incidence of anterior cruciate ligament injury patterns in Japanese judo players from a nationwide insurance database.

Objective: This study aimed to characterize the age- and sex-specific Anterior cruciate ligament (ACL) injury rates and related injury patterns in judo players in Japan using the nationwide insurance database. Methods: This was a descriptive epidemiological study. We examined a total of 2142 adolescents with anterior cruciate ligament injuries registered in the insurance system of the Japan Sports Council between January 2009 and December 2018. The age- and sex-specific incidences were estimated for the levels of 7th, 8th, and 9th grades of junior high school and 10th, 11th, and 12th grades of high school. The anterior cruciate ligament injury circumstances were classified into three patterns based on the impact to the involved knee: high-impact valgus force, low-impact trunk displacement, or no-impact knee twisting. Results: The incidence of anterior cruciate ligament injury from the 7th to 12th grades were 0.5, 0.9, 0.9, 6.9, 8.6, and 6.1 per 1000 athlete-years in male players and 1.3, 3.8, 3.4, 16.8, 19.5, and 13.6 per 1000 athlete-years in female players. The most prevalent injury pattern was a low-impact contact injury (42.6%) with Osoto-gari, followed by a high-impact contact injury (29.8%). The concomitant medial collateral ligament (MCL) injury rate was 18.1%, which was correlated with a high-impact contact injury (p = 0.005) by multiple regression analysis. Conclusions: The highest incidence of age- and sex-specific anterior cruciate ligament injury was 19.5 per 1000 athlete-years in female high school students in the 11th grade. The most frequent injury pattern was low-impact contact injury with trunk displacement, indicating that trunk stabilization training could help prevent anterior cruciate ligament injury in judo.

Effectiveness of a Judo Intervention Programme on the Psychosocial Area in Secondary School Education Students.

Currently, many combat sports are pedagogically conceived as uneducational and unreliable for the development of young people. The present research aims to investigate the influence of a Judo intervention programme on the motivational climate towards sport, aggressive behaviour, emotional intelligence, and self-concept in secondary school students and to establish the relationships between them. This objective was broken down into (a) developing an explanatory model of the variables mentioned above and (b) testing the model equations through a multi-group analysis in terms of pre-test and post-test. The present study conducted a pre-post-test quasi-experimental design with a single experimental group. The sample consisted of a total of 139 adolescents (12.67 ± 1.066), 50.4% of whom were male (n = 70) and 49.6% female (n = 69). The results show that the intervention decreased all types of aggression and increased levels of emotional intelligence. An increase in social, physical and academic self-concept and decreases in the family and emotional areas were also observed. Finally, for the motivational climate, a tendency towards the ego climate to the detriment of the task climate was observed. It is concluded that the Judo intervention programme is effective in decreasing aggressive behaviour and effective in increasing levels of emotional intelligence and self-concept.