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.

The effects of training type and area size variations on the physiological and session rating of perceived exertion responses during male judo matches.

Modified exercise prescription in judo is commonly used to activate the energy systems in different magnitudes. In order to study the physiological and rating of perceived exertion (RPE) responses according to area sizes (i.e., 4 m × 4 m, 6 m × 6 m and 8 m × 8 m) and training mode variations (i.e., groundwork, ne-waza; standing combat only, tachi-waza; and free combat, free randori), eighteen male judo athletes (age: 22.6 ± 1.8 years) were randomly assigned, on separate days, to 9 experimental conditions (3 area sizes × 3 training modes) with each condition lasting 4 min. Delta lactate [La] was calculated based on the blood lactate values measured before and after every condition. Heart rate (HR) was measured during and after each bout and RPE recorded at the end of each combat. The results showed that mean and peak HR, percentage of maximum HR (% HRmax), delta [La] values and RPE scores were lower in 4 m × 4 m compared to 6 m × 6 m and 8 m × 8 m, and in groundwork training mode compared to standing combat and free randori (all p < 0.001). Furthermore, the 6 m × 6 m condition induced lower delta [La] values than 8 m × 8 m (p < 0.001) and free randori resulted in higher RPE scores than standing combat (p = 0.001). In conclusion, different training variables can be easily manipulated in a variety of different ways to specifically activate the energetic systems. Focusing on groundwork, the 6 m × 6 m area size was found to be the most suitable condition to induce a higher cardiovascular response, while the standing combat and free randori in 6 m × 6 m resulted in increased glycolytic activation compared to the groundwork condition.

Health-promoting effect for students from physical loads of speed and strength orientation.

OBJECTIVE: Aim: To investigate the impact of speed and strength physical loads on promoting health and reducing the biological age of student youth. PATIENTS AND METHODS: Materials and Methods: The research involved 180 students aged 18-19. The first stage provided for the study of the indicators of the biological age of 120 students, and the second stage covered substantiation of the methodology for martial arts training sessions, based on physical loads of speed and strength orientation. To test its effectiveness, 60 students were involved (30 were in the experimental group (EG), 30 - in the control group (CG)). RESULTS: Results: The methodology for martial arts training sessions was developed and tested. In the dynamics of the experiment, there is a tendency to a decrease in the difference between the biological and the passport age, but these changes were unreliable in the CG, while a statistically significant decrease in this difference was recorded in the EG. In addition, there were significant changes in the EG in the following indicators: inspiratory breath holding (11.6 %), subjective health assessment (38.5 %), and static balancing (20.0 %). CONCLUSION: Conclusions: The use of physical loads of speed and strength orientation in the course of martial arts training has established a health-promoting effect and positive dynamics of the biological age indicators of student youth. The results of the research can be implemented in physical education and the process of sports improvement of students in higher educational institutions.

Acute Effects of the Dry Needling Session on Gastrocnemius Muscle Biomechanical Properties, and Perfusion with Latent Trigger Points - A Single-Blind Randomized Controlled Trial in Mixed Martial Arts Athletes.

The study aimed to evaluate the immediate effects of a dry needling (DN) therapy session on biomechanical properties, muscle power, perfusion, and pressure pain threshold of the gastrocnemius muscle with latent trigger points. Twenty mixed martial arts athletes (MMA) were randomly divided into two groups: experimental (eDN, n = 10) and sham (qDN, n = 10) to undergo one session of DN either with a real or a qazi needle. The measurements were taken at rest, 1-5 minutes after the DN (Post1-5min) and 24h after the DN (Post24h). DN significantly increased the muscle perfusion (Post1-5min and Post24h, p < 0.001), reduced its tone (Post1-5min and Post24h, p < 0.001) and stiffness (Post1-5min, p < 0.05; Post24 h, p < 0.001), and improved its elasticity (Post1-5min and Post24h, p < 0.001). DN also caused a significant increase in pressure pain threshold (Post1-5min, p < 0.001; Post24h, p < 0.05) and in muscle power (Post24h, p < 0.01). The DN session increased the blood perfusion and improved the biomechanical properties of the gastrocnemius muscle, which led to improved muscle power. The DN also had an analgesic effect. These effects were maintained at 24 h, which suggests that DN could facilitate muscle recovery in a post-exercise period of MMA athletes.

Comparing The Effects of Compression Contrast Therapy and Dry Needling on Muscle Functionality, Pressure Pain Threshold, and Perfusion after Isometric Fatigue in Forearm Muscles of Combat Sports Athletes: A Single-Blind Randomized Controlled Trial.

The aim of this study was to compare the acute effects of compression contrast therapy (CT) and dry needling therapy (DN) on muscle tension (MT), muscle strength (Fmax), pressure pain threshold (PPT), and perfusion (PU) following fatigue of forearm muscles (e.g., flexor carpi radialis) in combat sports athletes. A single-blind randomized controlled trial was employed. Participants first underwent muscle fatigue induction, which involved sustaining an isometric handgrip at 60% of their maximum voluntary contraction in 5-second cycles. This was followed by exposure to one of the regenerative therapies. Forty-five participants were randomly assigned to one of three groups: CT/DN (n = 15), CT/ShDN (n = 15), and ShCT/DN (n = 15). The sham condition (Sh) involved a simulated version of the technique. Measurements were taken at four time points: (i) at rest; (ii) immediately after exercise that led to a state of fatigue; (iii) 5 minutes after therapy (PostTh5min); and (iv) 24 hours after therapy (PostTh24h). Each participant was exposed to one experimental condition and one control condition, thereby undergoing evaluation in two sessions. Significant differences between groups were found in MT during the PostTh5min (p = 0.005), as well as in PU during the PostTh5min (p < 0.001) and PU during the PostTh24h (p < 0.001). All groups showed significant improvements at 5 minutes post-therapy compared to immediately post-muscle fatigue. As conclusions, CT/DN seems to be significantly better for enhancing MT and PU after 5 minutes of muscle fatigue induction. Using either CT, DN, or both combined is recommended to enhance the recovery of muscle functionality and properties, favoring recovery and potentially speeding up performance enhancement.

The "teacher" and martial arts: A psychobiographical analysis of Jack Ma as a business change agent.

OBJECTIVE: Scholars have conducted in-depth research on social change agents, but there are few collaborative studies in this realm between sociology and psychology. From the perspective of psychobiography, this before study uses Jung's Analytical Psychology as a theoretical framework to explore Jack Ma's influence on business change, thereby revealing the deep motivation behind Jack Ma's sudden retirement and choice to be a teacher. METHOD: This study has collected primary and secondary data about Jack Ma. QSR Nvivo 11.0 was used to encode the text based on video transcription, and then the data were analyzed. This study refers to the key factors of growth and follows the primary indicators of psychological saliency to sort out the data and find out what has special psychological significance, and then conducts three coding processes. RESULTS: This study found that the teacher complex and the martial arts complex are the breakthrough points to understand the business innovator Jack Ma. CONCLUSION: Jack Ma shapes the image of ordinary teachers through his image management strategy, conceals his deep internal martial arts complex, and balances the displayed martial arts personality mask. He has achieved great success in business innovator, while drawing on his internal personality conflicts to his advantage.

Effectiveness of a judo-specific injury prevention programme: a randomised controlled trial in recreational judo athletes.

OBJECTIVES: To evaluate the effectiveness of a trainer-supervised judo-specific injury prevention warm-up programme on overall injury prevalence. METHODS: We conducted a two-arm, cluster randomised controlled trial; the Injury Prevention and Performance Optimization Netherlands (IPPON) study. Judo athletes aged≥12 years were randomised by judo school to IPPON intervention or control group who performed their usual warm-up. Primary outcome was overall injury prevalence (%) over the follow-up period (16-26 weeks) measured fortnightly with the Oslo Sports and Trauma Research Centre Questionnaire. A modified intention-to-treat analysis was performed due to COVID-19, with estimates for the primary outcome obtained using generalised linear mixed models. Secondary outcomes included: prevalence of severe injuries, overall incidence, time-loss injuries, exposure, adherence and experiences of trainers and athletes. RESULTS: 269 judo athletes (IPPON: 117, Control: 152) were included. Mean injury prevalence over 16-26 weeks was 23% (95% CI 20% to 26%) in the IPPON and 28% (95% CI 25% to 30%) in the control group. We observed no significant difference of all reported injuries (OR 0.72 in favour of the IPPON group; 95% CI 0.37 to 1.39). Secondary outcomes also demonstrated no significant differences between groups. Specifically, no significant difference of severe injuries was reported (OR 0.80 in favour of the IPPON group; 95% CI 0.36 to 1.78). All trainers and 70% of athletes perceived the IPPON intervention as successful. CONCLUSION: The IPPON intervention did not significantly reduce the overall and severe injury prevalence. Despite this, we suggest the IPPON intervention be considered as an useful alternative to regular judo warm-up, given the high adherence and the positive clinical experiences of trainers and athletes. TRIAL REGISTRATION NUMBER: NTR7698.

An Attempt to Develop a Model of Brain Waves Using Quantitative Electroencephalography with Closed Eyes in K1 Kickboxing Athletes-Initial Concept.

BACKGROUND: Brain injuries are a common problem in combat sports, especially in disciplines such as kickboxing. Kickboxing is a combat sport that has several variations of competition, with the most contact-oriented fights being carried out under the format of K-1 rules. While these sports require a high level of skill and physical endurance, frequent micro-traumas to the brain can have serious consequences for the health and well-being of athletes. According to studies, combat sports are one of the riskiest sports in terms of brain injuries. Among the sports disciplines with the highest number of brain injuries, boxing, mixed martial arts (MMA), and kickboxing are mentioned. METHODS: The study was conducted on a group of 18 K-1 kickboxing athletes who demonstrate a high level of sports performance. The subjects were between the ages 18 and 28. QEEG (quantitative electroencephalogram) is a numeric spectral analysis of the EEG record, where the data is digitally coded and statistically analysed using the Fourier transform algorithm. Each examination of one person lasts about 10 min with closed eyes. The wave amplitude and power for specific frequencies (Delta, Theta, Alpha, Sensorimotor Rhythm (SMR), Beta 1, and Beta2) were analysed using 9 leads. RESULTS: High values were shown in the Alpha frequency for central leads, SMR in the Frontal 4 (F4 lead), Beta 1 in leads F4 and Parietal 3 (P3), and Beta2 in all leads. CONCLUSIONS: The high activity of brainwaves such as SMR, Beta and Alpha can have a negative effect on the athletic performance of kickboxing athletes by affecting focus, stress, anxiety, and concentration. Therefore, it is important for athletes to monitor their brainwave activity and use appropriate training strategies to achieve optimal results.

Viewpoint-Agnostic Taekwondo Action Recognition Using Synthesized Two-Dimensional Skeletal Datasets.

Issues of fairness and consistency in Taekwondo poomsae evaluation have often occurred due to the lack of an objective evaluation method. This study proposes a three-dimensional (3D) convolutional neural network-based action recognition model for an objective evaluation of Taekwondo poomsae. The model exhibits robust recognition performance regardless of variations in the viewpoints by reducing the discrepancy between the training and test images. It uses 3D skeletons of poomsae unit actions collected using a full-body motion-capture suit to generate synthesized two-dimensional (2D) skeletons from desired viewpoints. The 2D skeletons obtained from diverse viewpoints form the training dataset, on which the model is trained to ensure consistent recognition performance regardless of the viewpoint. The performance of the model was evaluated against various test datasets, including projected 2D skeletons and RGB images captured from diverse viewpoints. Comparison of the performance of the proposed model with those of previously reported action recognition models demonstrated the superiority of the proposed model, underscoring its effectiveness in recognizing and classifying Taekwondo poomsae actions.

An IoT Sensing Platform and Serious Game for Remote Martial Arts Training.

We propose a system for self-supported martial arts training using an IoT sensing platform and Serious Game that can also be extended for general sports training. In martial arts, it is important that the practitioner is correctly performing each technique to accurately learn and prevent injury. A common stance in all martial arts, but especially in Shaolin Kung Fu, is the horse stance or Mabu. With the pandemic, many more people adopted remote training without the presence of a professional trainer to give advice. Our developed LifeMat system, which is a novel IoT pressure-sensitive training mat, uses pressure maps and pattern recognition to accurately classify key martial arts postures, provide feedback on form, and detect when the user performs the technique incorrectly. This is presented in the form of a Serious Game we have developed named Kung Future that focuses on the Mabu stance as a case study. We tested 14 participants with three different feedback conditions and demonstrated that, on average, participants had higher performance, duration, engagement, and motivation when game feedback was active. Furthermore, user responses from the surveys suggested positive feedback for real-world and long-term use and scalability.

Influence of the Backward Fall Technique on the Transverse Linear Acceleration of the Head during the Fall.

BACKGROUND: The formation of large accelerations on the head and cervical spine during a backward fall is particularly dangerous due to the possibility of affecting the central nervous system (CNS). It may eventually lead to serious injuries and even death. This research aimed to determine the effect of the backward fall technique on the linear acceleration of the head in the transverse plane in students practicing various sports disciplines. METHODS: The study involved 41 students divided into two study groups. Group A consisted of 19 martial arts practitioners who, during the study, performed falls using the side aligning of the body technique. Group B consisted of 22 handball players who, during the study, performed falls using the technique performed in a way similar to a gymnastic backward roll. A rotating training simulator (RTS) was used to force falls, and a Wiva® Science apparatus was used to assess acceleration. RESULTS: The greatest differences in backward fall acceleration were found between the groups during the buttocks' contact with the ground. Larger changes in head acceleration were noted in group B. CONCLUSIONS: The lower changes in head acceleration obtained in physical education students falling with a lateral body position compared to students training handball indicate their lower susceptibility to head, cervical spine, and pelvis injuries when falling backwards as caused by horizontal force.

Meditation reduces brain activity in the default mode network in children with active cancer and survivors.

BACKGROUND: Mounting evidence demonstrates that meditation can lower pain and emotional distress in adults, and more recently, in children. Children may benefit from meditation given its accessibility across a variety of settings (e.g., surgical preparation). Recent neuroimaging studies in adults suggest that meditation techniques are neurobiologically distinct from other forms of emotion regulation, such as distraction, that rely on prefrontal control mechanisms, which are underdeveloped in youth. Rather, meditation techniques may not rely on "top-down" prefrontal control and may therefore be utilized across the lifespan. PROCEDURE: We examined neural activation in children with cancer, a potentially distressing diagnosis. During neuroimaging, children viewed distress-inducing video clips while using martial arts-based meditation (focused attention, mindful acceptance) or non-meditation (distraction) emotion regulation techniques. In a third condition (control), participants passively viewed the video clip. RESULTS: We found that meditation techniques were associated with lower activation in default mode network (DMN) regions, including the medial frontal cortex, precuneus, and posterior cingulate cortex, compared to the control condition. Additionally, we found evidence that meditation techniques may be more effective for modulating DMN activity than distraction. There were no differences in self-reported distress ratings between conditions. CONCLUSION: Together, these findings suggest that martial arts-based meditation modulates negative self-referential processing associated with the DMN, and may have implications for the management of pediatric pain and negative emotion.

Individual responsiveness to a school-based karate intervention: An ancillary analysis of a randomized controlled trial.

INTRODUCTION: School-based sport interventions have shown beneficial effects on psychosocial functioning and academic performance in children. However, the inter-individual variability in response to these types of interventions remains unclear. We aimed to determine which children benefit most from a school-based sport intervention. METHODS: This is an ancillary analysis of a randomized controlled trial assessing the effects of a 1-year school-based karate intervention (versus "traditional" physical education lessons) in children (7-8 years) from twenty schools across five European countries. Outcomes included psychosocial functioning (Strengths and Difficulties Questionnaire [SDQ] for parents) and academic performance (grade point average). Only participants of the intervention group were included in the present ancillary analysis, and were categorized as responders or non-responders for the analyzed outcomes attending to whether improvements surpassed a minimal clinically important difference. RESULTS: About 388 children (187 girls) from the intervention group completed the study, of which 17% and 46% were considered responders for SDQ and academic performance, respectively. Responders for the SDQ presented higher SDQ scores (i.e., higher psychosocial difficulties) at baseline than non-responders (p < 0.001). Responders for academic performance were mostly males (p = 0.017), with an older age (p = 0.030), and with worse academic performance (p < 0.001) at baseline compared with non-responders, and tended to present higher SDQ scores (p = 0.055). Responders for one outcome obtained greater benefits from the intervention on the other outcome (e.g., responders for SDQ improved academic performance [p < 0.001] compared with non-responders). CONCLUSIONS: A school-based sport intervention (karate) seems particularly effective for children with psychosocial difficulties and low academic performance.

Facial width-to-height ratio predicts fighting success: A direct replication and extension of Zilioli et al. (2014).

Zilioli et al. (2014) were the first to show an association between male facial width-to-height ratio (fWHR) and physical aggression and fighting ability in professional mixed-martial-arts fighters. Here, we re-examined this relationship by replicating (using all original measures) and extending (using 23 new variables related to fighting performance) Zilioli et al. (2014) in a statistically well-powered sample of 520 fighters using automatic and manual measures of the fWHR involving both eyelid and eyebrow landmarks, used interchangeably in previous reports (Studies 1-2). Most importantly, we successfully replicated Zilioli et al.'s (2014) central finding that fighters' fWHR, when manually calculated using the eyebrow landmark, predicted their fighting success (p = .004, controlling for body mass index and total fights). Consistent with past criticisms of using fight rather than fighter data to examine fighting success, which have argued that individual fights can be suddenly and unexpectedly determined and do not capture an individual's overall ability to succeed, Study 3 (N = 1367 fights) found no association between fWHR and singular victories. Studies 1-3 showed continual evidence that larger fWHRs were associated with grappling abilities, even after controlling for demographic and allometric factors. Strikingly, Study 3 discovered associations between all fWHR measures and grappling skill that remained robust before and after controlling for 17 different control variables. We discuss that grappling, or the act of taking down an opponent, involves a more aggressive, close-combat approach than does striking. Combined, these results offer additional support for the argument that fWHR may have been shaped by sexual selection.

Karate Training Improves Metabolic Health in Overweight and Obese Adolescents: A Randomized Clinical Trial.

PURPOSE: This study evaluated the effects of 12 weeks of karate training on cardiometabolic parameters, oxidative stress, and inflammation in adolescents with overweight and obesity. METHOD: Seventy adolescents were randomized into 2 groups: control received nutritional and psychological interventions once a week for 12 weeks, and treatment received nutritional and psychological interventions once a week, plus 3 karate sessions per week, for 12 weeks. The main outcome measure was improvement in cardiometabolic parameters, oxidative stress, and inflammation. RESULTS: After the intervention period, the treatment group showed a reduction in resting heart rate (77.86 [10.89]), high-density lipoprotein cholesterol (40.86 [8.31]), and triglycerides (75.18 [32.29]) and an increase in low-density lipoprotein cholesterol (95.64 [42.53]) in relation to pretraining. Regarding oxidative stress markers, there was a reduction in protein carbonylation (0.07 [0.06]) and nitric oxide (1.39 [1.11]) and an increase in superoxide dismutase (0.68 [0.31]) and glutathione (0.11 [0.08]) compared with pretraining. With respect to inflammation, adiponectin increased (14.54 [5.36]) after the intervention when compared with preintervention. CONCLUSION: The study concluded that the intervention may improve cardiometabolic parameters, oxidative stress, and inflammation in adolescents with overweight and obesity. Long-term effects need to be evaluated.

Assessment of the Relevance and Reliability of Reaction Time Tests Performed in Immersive Virtual Reality by Mixed Martial Arts Fighters.

Immersive virtual reality (VR) is increasingly applied in various areas of life. The potential of this technology has also been noticed in recreational physical activity and sports. It appears that a virtual environment can also be used in diagnosing certain psychomotor abilities. The main aim of this study consisted of assessing the relevance and reliability of VR-implemented tests of simple and complex reaction time (RT) performed by mixed martial arts (MMA) fighters. Thirty-two professional MMA fighters were tested. The original test developed in the virtual environment was applied for RT assessment. The fighters' task consisted of reacting to the lighting up of a virtual disc situated in front of them by pushing a controller button. The relevance of the test task was estimated by juxtaposing the obtained results with the classic computer test used for measuring simple and complex reactions, while its reliability was assessed with the intraclass correlation procedure. Significant relationships found between the results of VR-implemented tests and computer-based tests confirmed the relevance of the new tool for the assessment of simple and complex RT. In the context of their reliability, RT tests in VR do not differ from tests conducted with the use of standard computer-based tools. VR technology enables the creation of tools that are useful in diagnosing psychomotor abilities. Reaction time tests performed by MMA fighters with the use of VR can be considered relevant, and their reliability is similar to the reliability obtained in computer-based tests.

Injuries in Judo Athletes With Disabilities: Prevalence, Magnitude, and Sport-Related Mechanisms.

CONTEXT: The participation of judo athletes with disabilities in competitions has increased over the years as well as the burden of sports-related injuries and illnesses in this population. However, there is limited knowledge about sports-related injuries in judo athletes with different disabilities. OBJECTIVE: To investigate the prevalence of injuries in judo athletes with disabilities, considering the different impairment groups, magnitude of injury (ie, mechanism, nature, and severity of injury), and specific body parts. DESIGN: Cross-sectional study (level of evidence, 3). SETTING: Brazilian Judo athletes with disabilities. PATIENTS: Fifty-one judo athletes with disabilities (15 men and 36 women) participated in this study. MAIN OUTCOME MEASURES: Data were obtained from an adapted injury report form. The prevalence of injuries was assessed, considering type of impairment, body parts, mechanisms, and severity as well as differences between male and female athletes, with the significance level set at P < .05. RESULTS: The results demonstrated a high prevalence of injuries in female athletes with visual impairment (n = 11, 73.3%) and male athletes with amputations (n = 14, 38.8%). A high prevalence was found in the national group, especially for male athletes (n = 29, 80.5%). Among athletes who had injuries, 69.4% (n = 12) of male and 80.0% (n = 25) of female athletes' injuries occurred due to direct contact with other athletes, and 72.2% (n = 26) of male and 86.6% (n = 13) of female athletes' injuries were in the training environment. The magnitude of injuries ranged from moderate to severe for male and female athletes. The knee (n = 25, 49.0%) and shoulder (n = 12, 23.5%) were the body parts most affected by injuries in both male and female athletes. CONCLUSION: A large percentage of judo athletes with disabilities reported experiencing an injury during the previous 2 years; percentages were greater in athletes with visual and physical impairment. Moreover, most injuries occurred in the knee or shoulder, during training, and in direct contact with other athletes and were of severe magnitude.

Validation of session ratings of perceived exertion for quantifying training load in karate kata sessions.

This study was intended to investigate the associations between session Ratings of Perceived Exertion (sRPE) and Edwards' training load (TL) and Banister training impulse (TRIMP) in order to determine the validity of the sRPE method for TL assessment in karate kata discipline. Eight elite karate kata athletes, members of the national karate team, took part in this study. A multistage 20 m shuttle run test was performed to determine maximal heart rate (HRmax). Subsequently, the subjects performed 3 different kata training sessions separated by minimally 48 hours. To calculate Edwards TL, Banister TRIMP and sRPE, heart rate (HR) was continuously monitored during the sessions and RPE of the entire session was collected 30 minutes after each training session. The Pearson correlation coefficient (r) was used for determining associations between TL variables. Edwards TL (p = 0.064) and Banister TRIMP (p = 0.102) were not, but sRPE was significantly different between each training session (p < 0.001). There were no significant correlations between sRPE and Edwards TL (r = 0.53, p = 0.18) or Banister TRIMP (r = 0.13, p = 0.77) when data from all training sessions were pooled. A significant correlation was obtained between sRPE and Edwards TL (r = 0.71, p = 0.04) in situational training session, whereas in technical training session sRPE was significantly correlated with Banister TRIMP (r = 0.82, p = 0.01). HR-based methods for TL assessment are not able to discriminate between kata training sessions and, therefore, sRPE may be more useful for coaches to monitor TL in karate kata athletes.

Reliability, criterion-concurrent validity, and construct-discriminant validity of a head-marking version of the taekwondo anaerobic intermittent kick test.

This study aimed to examine the reliability and validity of a head-marking version of the taekwondo anaerobic intermittent kick test (TAIKT-head). Twenty-seven (21 males and 6 females) taekwondo athletes performed TAIKT-head on two occasions (test-retest). In addition, they performed the chest-marking version of the TAIKT (TAIKT-chest), 30-s continuous jump (CJ30s), countermovement jump (CMJ) and flexibility tests. To establish TAIKT-head's construct validity (discriminatory capability), two subgroups were identified based on their international and national taekwondo results: 15 elite (12 males and 3 females) and 12 sub-elite (9 males and 3 females) athletes. TAIKT-head showed high relative (ICCs ≥ 0.90) and absolute (SEMs < SWCs) reliability. The comparison between TAIKT-head and TAIKT-chest revealed that absolute and relative peak and mean powers were higher (p < 0.001) in TAIKT-head than in TAIKT-chest. In contrast, the fatigue index and rating of perceived exertion were lower in TAIKT-head than in TAIKT-chest (p < 0.001 and p < 0.01, respectively), with no significant difference between the two tests regarding physiological variables. Significant correlations between TAIKT-head and TAIKT-chest (r ranged from 0.74 to 0.53), CJ30s (r ranged from 0.84 to 0.43), and CMJ (r ranged from 0.88 to 0.79) were mostly "very large". There was no association between TAIKT-head and flexibility tests. Elite athletes showed greater TAIKT-head performances than sub-elite counterparts. Receiving operating characteristic analysis indicated that the TAIKT-head effectively discriminated between elite and sub-elite athletes. In conclusion, the TAIKT-head is a reliable and valid test to evaluate the specific intermittent anaerobic power of taekwondo athletes through the most used kicking technique at the head level.

Differences in Sports Injury Types According to Taekwondo Athlete Types (Sparring, Poomsae, and Demonstration).

The objective of this study was to investigate the range of injuries according to the competition format type of Taekwondo (sparring, poomsae, and demonstration) and compare the level of injuries to provide basic data for preventing injuries among Taekwondo athletes. Data were collected through a survey of 472 Taekwondo athletes using convenience sampling and self-administration methods. The most frequently injured body part was the ankle for sparring (54.03%) and demonstration (55.09%) athletes and the pelvis for poomsae (36.36%) athletes (x2 = 111.556, p < 0.001). The most frequent injury type was sprain for poomsae (36.40%) and demonstration (52.30%) athletes and fracture for sparring (49.40%) athletes (x2 = 127.752, p < 0.001). The most frequently reported cause of injury was excessive training and chronic fatigue (x2 = 50.251, p < 0.001). All three types of athletes showed a higher proportion of injury at the training location than at the competition location. The period for the return to training was ≤1 week for sparring (40.80%) and poomsae (64.10%) athletes but 2-3 weeks for demonstration (27.8%) athletes (x2 = 45.582, p < 0.001). Diverse strategies, ranging from wearing protective gear to adopting a conditioning strategy and psychological training, are needed for each competition format of Taekwondo to prevent injuries in daily training.