Search Results (97)

Background: This study aimed to develop a method to analyze the kinetic and kinematic characteristics of the traditional karate Gyaku Tsuki (reverse punch), focusing on the activation sequence of lower and upper extremities and trunk muscles during execution. Methods: An elite male (N = 1) karate athlete (in kata) performed 20 Gyaku Tsuki punches while equipped with 16 wireless surface EMG sensors integrated with 3-axis accelerometers. The five punches with the highest forearm acceleration were selected for analysis. EMG, accelerometer, and synchronized video data were recorded and processed. Results: A novel visualization technique was developed to represent muscle activation over time, distinguishing a spectrum of 0–25–50–75–100% activation levels. Muscle activation times for arm, leg, and trunk muscles ranged from −0.31 to −0.11 s relative to punch execution, indicating rapid, coordinated muscle engagement. Conclusions: This method enables detailed analysis of muscle activation patterns in karate punches. It offers valuable insights for biomechanics researchers and practical applications for coaches aiming to enhance performance and prevent injuries through better understanding of movement dynamics. Full article

Kumite is a karate sparring competition in which two players fight each other using various techniques. In kumite matches, it is essential to reduce a preliminary action (hereinafter referred to as “pre-action”), such as pulling the arms and lowering the shoulders just before performing an attack technique. This is because pre-actions reveal the timing of the attack to the opponent. However, players often find it difficult to recognize their own pre-actions, and accurately estimating their presence or absence is challenging with conventional motion analysis methods, as pre-actions are subtle compared to major techniques like punching or kicking. Previously, we proposed a method for detecting pre-actions during single punches performed in a static state using inertial sensors. While this method was effective in controlled situations, it failed to detect pre-actions in punches during actual kumite matches. The main reason is that players generally perform footwork during matches, and this footwork is often misrecognized as pre-action via conventional detection methods. To address misrecognition caused by footwork, we propose a new method that combines preprocessing designed to detect and smooth footwork segments in the inertial data with the conventional pre-action detection method, thereby enabling pre-action detection during kumite matches. In the preprocessing, we apply an autocorrelation function to assess the constancy of footwork and accurately separate the footwork segment from the kumite technique segment. Only the footwork segment is then smoothed to suppress its influence on the detection process. Our experimental results show that the proposed method can estimate the presence or absence of pre-action in the punch of an actual kumite match with an accuracy of 0.875. Full article

Objectives: This study aimed to compare the involuntary stimulated neuromuscular response of thigh muscles in karate subgroups and non-athletes. We investigated whether karate training creates neuromuscular adaptations and if the synchronization of knee flexor and extensor muscles in karate practitioners is level-dependent. Methods: The study included 7 elite karate athletes (KE), 14 sub-elite karate athletes (KSE), 16 individuals with basic karate training (KB), and 14 non–athletes (NA). Tensiomyographic (TMG) measurements were obtained from the rectus femoris, vastus medialis, vastus lateralis, biceps femoris, and semitendinosus muscles. Indexes of Intermuscular Synchronization (IIS) were calculated for contraction time (Tc), total contraction time (TcT), and rate of muscle tension development (RMTD) as variables for the observed muscles of a given muscle group (extensors of the dominant leg, flexors of the dominant leg, extensors of the non-dominant leg, and flexors of the non-dominant leg). Results: Statistically significant differences were observed in the intermuscular synchronization indexes between karate experience levels and non-athletes. Compared to non-athletes, elite (KE), sub-elite (KSE), and beginner karateka (KB) all demonstrated shorter contraction time indexes in dominant knee extensors (p = 0.042, 0.040, and 0.013, respectively). In the non-dominant flexors, KE exhibited significantly better synchronization than KSE (p = 0.001), KB (p = 0.033), and NA (p = 0.002). For the total contraction time index, both KSE and KB outperformed NA in dominant extensors (p = 0.023 and p = 0.008), while KE showed superiority in non-dominant extensors and flexors compared to all other groups (p-values ranging from 0.002 to 0.038). Significant RMTD differences were found in the dominant leg between KE and KSE (p = 0.036) and KE and KB (p = 0.001), as well as in the non-dominant leg between KE and KB (p = 0.011) and KE and NA (p = 0.025). These findings were accompanied by statistical powers exceeding 0.80 in most cases, underscoring the robustness of the observed differences. Conclusions: These findings highlight that muscle coordination patterns, as revealed through non-invasive TMG-based indexes, are sensitive to training level and laterality in karate practitioners. Importantly, elite athletes demonstrated more synchronized activation in key muscle groups, suggesting a neuromuscular adaptation specific to high-level combat sports. From a biomechanical perspective, improved intermuscular synchronization may reflect optimized neural strategies for stability, speed, and efficiency—key components in competitive karate. Thus, this method holds promise not only for performance diagnostics but also for refining individualized training strategies in combat sports and broader athletic contexts. Full article

Introduction: Combat sport athletes are exposed to repetitive head impacts yet also develop distinct performance-related brain adaptations. Electroencephalography (EEG) provides millisecond-level insight into both processes; however, findings are dispersed across decades of heterogeneous studies. This mechanistic review consolidates and interprets EEG evidence to elucidate how participation in combat sports shapes brain function and to identify research gaps that impede clinical translation. Methods: A structured search was conducted in March 2025 across PubMed/MEDLINE, Scopus, Cochrane Library, ResearchGate, Google Scholar, and related databases for English-language clinical studies published between January 1980 and March 2025. Eligible studies recorded raw resting or task-related EEG in athletes engaged in boxing, wrestling, judo, karate, taekwondo, kickboxing, or mixed martial arts. Titles, abstracts, and full texts were independently screened by two reviewers. Twenty-three studies, encompassing approximately 650 combat sport athletes and 430 controls, met the inclusion criteria and were included in the qualitative synthesis. Results: Early visual EEG and perfusion studies linked prolonged competitive exposure in professional boxers to focal hypoperfusion and low-frequency slowing. More recent quantitative studies refined these findings: across boxing, wrestling, and kickboxing cohorts, chronic participation was associated with reduced alpha and theta power, excess slow-wave activity, and disrupted small-world network topology—alterations that often preceded cognitive or structural impairments. In contrast, elite athletes in karate, fencing, and kickboxing consistently demonstrated neural efficiency patterns, including elevated resting alpha power, reduced task-related event-related desynchronization (ERD), and streamlined cortico-muscular coupling during cognitive and motor tasks. Acute bouts elicited transient increases in frontal–occipital delta and high beta power proportional to head impact count and cortisol elevation, while brief judo chokes triggered short-lived slow-wave bursts without lasting dysfunction. Methodological heterogeneity—including variations in channel count (1 to 64), reference schemes, and frequency band definitions—limited cross-study comparability. Conclusions: EEG effectively captures both the adverse effects of repetitive head trauma and the cortical adaptations associated with high-level combat sport training, underscoring its potential as a rapid, portable tool for brain monitoring. Standardizing acquisition protocols, integrating EEG into longitudinal multimodal studies, and establishing sex- and age-specific normative data are essential for translating these insights into practical applications in concussion management, performance monitoring, and regulatory policy. Full article

Background/Objectives: Acute dehydration, commonly induced through fluid restriction and/or excessive sweating, is a common weight-cutting strategy among combat sport athletes. However, its impact on muscle strength and power remains a concern. The aim of the study was to evaluate the impact of 2% body mass reduction via dehydration on lower-limb strength and power in elite karate athletes. Methods: Fourteen male elite karate athletes completed two conditions: euhydrated (EUH) and dehydrated (DEH) (−2% body mass via 24-h fluid restriction). Performance was assessed using squat jump (SJ) and countermovement jump (CMJ) tests, along with isokinetic knee flexion and extension at 60, 180, and 300°/s. Results: Dehydration significantly reduced squat jump height (37.19 ± 3.69 vs. 39.34 ± 5.08 cm (EUH), p = 0.04), power output (2188.2 ± 307.2 vs. 2351.1 ± 347.2 W (EUH), p = 0.001), and knee extension and flexion strength at 60°/s (p = 0.018). CMJ height and higher-velocity knee flexion/extension were unaffected (p > 0.05). Conclusions: Acute dehydration impairs lower-body maximal force production at low velocities but has no significant effect on high velocity movements. Athletes and coaches should carefully manage hydration strategies when “cutting weight” to avoid any negative performance effects. Full article

Objectives: The present study examined the sensory preferences adopted by students over three years of training in a specialized training program for security forces (STPSF). It determines their impact on karate performance metrics. Methods: Thirty-one students aged 20 to 26 (SD = 0.81) completed the modified Visual, Aural, Read/Write, and Kinesthetic questionnaire (VARK), a tool designed to help identify students’ preferred learning styles. This research suggests a theoretical model in which the balanced and optimal engagement of visual, auditory, and kinesthetic modalities rather than a strict mathematical equation might provide an optimal foundation for improving proficiency in martial arts. Balanced engagement of these sensory modalities can foster a deeper understanding of karate techniques, improve performance, minimize dependence on a single sensory channel, and bolster real-time adaptability. The students were tested at two points: once at the beginning of their enrolment and again after completing their three-year training program. Results: After a relatively intensive intervention over three years, the findings suggest a positive shift in the ratio of the primary modalities, moving toward an optimal balance. Considering the ideal sensory balance of 50:50:50%, the visual modality increased from 45.8 to 50.4, approaching the optimal value. The auditory modality, initially above the ideal level at 53.8, adjusted closer to balance, reaching 51.9. In contrast, the kinesthetic modality slightly decreased from 50 to 47.5, indicating a minor deviation from the ideal state. It was further confirmed that a higher technical level, such as the third kyu, exhibits an equal distribution, approaching the optimal use of the three modalities: visual 51.5 auditory 47.6 and kinesthetic 50.7. Moreover, the progress toward an optimal synergy and a more efficient evaluation of situational possibilities within the decision-making process was more frequently noted in females than in male students. Conclusions: Acknowledging students’ sensory processing preferences can assist the teacher, trainer, coach, and student in advancing interaction, optimizing learning strategies, improving performance, promoting analytical skills, and fostering self-assurance and determination. Full article

Biosensors as advanced analytical tools have found various applications in food safety, healthcare, and environmental monitoring in rapid and specific detection of target analytes in small liquid samples. Up to now, planar electrochemical electrodes have shown the highest potential for biosensor applications due to their simple and compact construction and cost-effectiveness. Although a number of commercially available electrodes, manufactured from various materials on different substrates, can be found on the market, their high costs for single use and low reproducibility persist as major drawbacks. In this study, we present an innovative, cost-effective approach for the rapid fabrication of electrodes that combines lamination of 24-karat gold leaves with low-cost polyvinyl chloride adhesive sheets followed by laser ablation. Laser ablation enables the creation of electrodes with customizable geometries and patterns with microlevel resolutions. The developed electrodes are characterized by cyclic voltammetry and electrochemical impedance spectroscopy, scanning electronic microscopy, and 3D profiling. To demonstrate the manufacturing and biosensing potential, different geometries and shapes of electrodes were realized as the electrochemical transducing platform and applied for the realization of magnetic bead (MB)-labeled biosensors for quantitative detection of food-borne pathogens of Salmonella typhimurium (S. typhimurium) and Listeria monocytogenes (L. monocytogenes). Full article

In combat sports, precise technique evaluation is crucial for performance optimization; however, traditional systems for evaluating kick performance are frequently unreasonably complicated and costly. This study offers a useful and accessible substitute by introducing a contact mat-based tool that measures the roundhouse kick’s execution time during both the attack and recovery phases and by demonstrating its reliability. The experimental sessions involved 16 male Shotokan karate athletes (age: 25.6 ± 7.1 years; height: 1.74 ± 0.05 m; body mass: 71.5 ± 8.7 kg; body fat percentage: 14.7 ± 6.7%; training experience: 11.0 ± 4.9 years). The protocol included four sessions, starting with a familiarization phase followed by three testing sessions (test, retest, and retest two), during which a standardized warm-up was performed along with the roundhouse kick test. The intraclass coefficient correlation (ICC) used indicated high reliability for the at-tack (ICC = 0.85, 95% CI [0.64, 0.94]), recovery (ICC = 0.89, 95% CI [0.75, 0.96]), and total time (ICC = 0.90, 95% CI [0.76, 0.96]). The Friedman test revealed no significant difference between testing sessions (p > 0.31), demonstrating high reliability and no significant differences between sessions. This study confirms the system as a simple and reliability tool for measuring roundhouse-kick timing in combat sports. Full article

Background/Objectives: This study aimed to examine differences in motor competence and muscular fitness between children engaged in combat sports and their peers who do not participate in structured physical activity. Methods: The sample consisted of 120 healthy eight-year-old children, evenly divided into two groups: 60 children practicing combat sports (karate, judo, and wrestling) for at least one year and 60 children without structured sports involvement. Motor competence was assessed using the Test of Gross Motor Development-2 (TGMD-2), while muscular fitness was evaluated through standing broad jump, grip strength, 30 s sit-ups, bent arm hang, medicine ball throw, and push-ups. For differences between groups, the independent samples t-test was performed. Results: Results indicated that children practicing combat sports demonstrated significantly higher locomotor and manipulative skills (p < 0.01, ES = 0.76–1.25) and superior muscular fitness across all tests (p < 0.01, ES = 0.53–1.09) compared to their peers. Conclusions: These findings highlight the positive impact of combat sports on overall physical development, particularly in enhancing motor competence, muscle strength, and endurance. Given the critical role of motor competence and physical fitness at this age, integrating combat sports into daily routines can support long-term athletic development, encourage physical activity, and enhance overall health. Future research should explore the influence of specific combat sports on distinct physical attributes and consider additional factors such as total physical activity levels. Full article

Background/Objectives: This study aimed to evaluate an artificial intelligence (AI)-enhanced electrocardiogram (ECG) screening protocol for improved accuracy, efficiency, and risk stratification across six sports: handball, football, athletics, weightlifting, judo, and karate. Methods: For each of the six sports, resting 12-lead ECGs from healthy children and junior athletes were analyzed using AI algorithms trained on annotated datasets. Parameters included the QTc intervals, PR intervals, and QRS duration. Statistical methods were used to examine each sport’s specific cardiovascular adaptations and classify cardiovascular risk predictions as low, moderate, or high risk. Results: The accuracy, sensitivity, specificity, and precision of the AI system were 97.87%, 75%, 98.3%, and 98%, respectively. Among the athletes, 94.54% were classified as low risk and 5.46% as moderate risk with AI because of borderline abnormalities like QTc prolongation or mild T-wave inversions. Sport-specific trends included increased QRS duration in weightlifters and low QTc intervals in endurance athletes. Conclusions: The statistical analyses and the AI-ECG screening protocol showed high precision and scalability for the proposed athlete cardiovascular health risk status stratification. Additional early detection research should be conducted further for diverse cohorts of individuals engaged in sports and explore other diagnostic methods that can help increase the effectiveness of screening. Full article

The aim of this study was to examine the perception and gender typing of sports among students at the University of Zagreb Faculty of Kinesiology. The study was conducted on a sample of 268 students, with respondents categorizing 19 sports as male, female, or equally male and female. Data processing included descriptive statistics in the form of frequencies and percentages and the chi-square test with Bonferroni correction to test differences between groups for categorical variables. Differences in gender typing (perception) between two groups of participants based on gender were tested using the t-test. Five sports (rugby, formula, boxing, water polo, and soccer) were predominantly categorized as “male”, three sports as “female” (rhythmic gymnastics, aerobics, and synchronized swimming), and as many as eleven as “neutral” (athletics, skiing, swimming, tennis, karate, beach volleyball, gymnastics, handball, volleyball, sailing, and basketball). Regardless of active participation in a particular sport, the perception of gender typing of sports remained constant. The results indicate that in Croatia there is still a separation in the perception of sports that are either suitable for men, for women, or for both genders. Full article

This study aimed to assess the acute impact of a simulated kumite bout (WKF formula) on peak isometric strength performance of the dominant and non-dominant lower limbs in elite karate athletes of different age categories (U16, U18, Senior), in the context of inter-limb asymmetry. Sixty-one elite male and female athletes (age = 17.48 ± 3.26 [years], body height = 1.72 ± 0.08 [m], body mass = 63.79 ± 10.00 [kg]) participated in this study, which included a randomized crossover design (two experimental sessions under two different conditions). Inter-limb asymmetry was assessed based on the isometric mid-thigh pull test. Friedman’s test indicated significant differences in the mean values of the peak vertical force (PVF) between the assessed limbs (test = 10.8; p = 0.013; Kendall’s W = 0.059). Elite karate athletes, regardless of the age category, tend to have inter-limb strength asymmetries in the lower extremities; however, the impact of a simulated kumite bout was not fully confirmed. A kumite bout seems to have a favorable impact on bilateral asymmetries in U16 and U18 athletes, but not in Seniors, who seem to be at increased risk of injury after completing the bout (asymmetry > 15%). Limb dominance is not necessarily related to greater values of PVF. Full article

Background and objectives: In karate, particularly in the kata discipline, there is a notable lack of studies focused on specific physical preparation for competitions. This highlights an urgent need for more in-depth research into this crucial aspect of athletic training to optimize performance and athlete preparation. The objective of this study was to analyze the influence of a dietary plan combined with specific physical preparation on the performance and body composition of a professional kata athlete preparing for a Pan American championship. Methods: A 20-year-old elite female karateka (60.7 kg, 165.4 cm) followed a nutritional plan with an isocaloric diet. The strength and power of the upper and lower limbs were evaluated through countermovement jump (CMJ) and one-repetition maximum (1RM) tests in bench press and free squat over a five-month period before the competition. Results: Following the nutritional plan and physical preparation, the athlete’s body composition improved in terms of fat loss (from 12.17% to 10.68%) and increased muscle mass (from 51.45% to 53.09%). Moreover, these improvements translated into better performance in tests such as CMJ (from 38.29 cm to 44.14 cm), 1RM bench press (from 54.5 kg to 67.6 kg), and 1RM free squat (from 65.1 kg to 78.4 kg). Conclusions: This study demonstrates that a comprehensive approach to personalized physical, technical, and nutritional preparation over 16 weeks significantly improves muscle strength and performance in karate kata. The novelty of this intervention lies in the detailed description of the total workload, encompassing both physical and technical performance, with a specific plan tailored to the athlete’s needs. Additionally, the preparation was precisely designed for a specific tournament, addressing the sport’s unique demands. Full article

Background/Objectives: To date, the health effects of karate have not been identified. Therefore, the aim of this article is to learn more about the health effects of karate training based on a review of current research. Methods: The Scopus database was searched from 2000 onwards for available articles related only to karate. The following intermediate phrases were not included: combat sport, fighting art, hand-to-hand combat, martial art, and self-defence system. The filter used was desk review analysis. Only 14 scientific articles (research papers and review papers) strictly on karate were found. The method of source material analysis and critical analysis of the source text was then used. Results: It was shown that kumite appears to require significantly more metabolic power than kata. Furthermore, the greater skill of karatekas is associated with their greater physical fitness, and long-term karate training attenuates the decline in dynamic visual acuity (DVA). The role of modified and individualised forms of karate training is also highlighted as important for the health of practitioners. Furthermore, long-term karate practice is associated with extensive modulation of immunological parameters. Karate training can also significantly improve motor skills. It can also play an important role in the development of willpower and personality traits that contribute to the well-being of its practitioners. Furthermore, nutritional and psychological interventions combined with karate training may improve cardiometabolic parameters, oxidative stress and inflammation. Karate training may also contribute to the prevention of osteoporosis and strengthen the left ventricular myocardium. Conclusions: It was found that there is a paucity of contemporary research on the health effects of karate training. In addition, they are limited to the individuals studied, so that generalisations about these effects in the general population of karate practitioners cannot be made. Full article

Striking velocity is a key performance indicator in striking-based combat sports, such as boxing, Karate, and Taekwondo. This study aims to develop a low-cost, accelerometer-based system to measure kick and punch velocities in combat athletes. Utilizing a low-cost mobile phone in conjunction with the PhyPhox app, acceleration data was collected and analyzed using a custom algorithm. This involved strike segmentation and numerical integration to determine velocity. The system demonstrated moderate reliability (intraclass correlation coefficient (ICC) $3,1$ = $0.746$ to $0.786$, standard error of measurement (SEM) = $0.488$ to $0.921$ m/s), comparable to commercially available systems. Biological and technical variations, as well as test standardization issues, were acknowledged as factors influencing reliability. Despite a relatively low sampling frequency, the hardware and software showed potential for reliable measurement. The study highlights the importance of considering within-subject variability, hardware limitations, and the impact of noise in software algorithms. Average strike velocities exhibited higher reliability than peak velocities, making them a practical choice for performance tracking, although they may underestimate true peak performance. Future research should validate the system against gold-standard methods and determine the optimal sampling frequency to enhance measurement accuracy. Full article