Maturity Status and Relative Age of Elite Taekwondo Youth Competitors-Case Study on Croatian National Team.

This study examines the maturity status and relative age effect in elite youth taekwondo Croatian National Team athletes. Measurements of biological age, maturity offset, and body composition were taken from a sample of 17 junior athletes. Differences in maturity status were observed among athletes of the same chronological age, with variations in sitting height and age at peak height velocity. Male athletes generally exhibited higher values in body height, percentage of body fat, muscle mass, and total body water. No significant relative age effect was found. These findings highlight the importance of considering individual biological age and maturity status for talent development and training program adjustments. Further research involving athletes from different countries is recommended to validate these results and enhance the understanding of youth taekwondo athlete development.

Tensiomyography: from muscle assessment to talent identification tool.

Introduction: Tensiomyography (TMG) is a non-invasive and cost-effective tool that is gaining popularity in fields such as sports science, physical therapy, and medicine. In this narrative review, we examine the different applications of TMG and its strengths and limitations, including its use as a tool for sport talent identification and development. Methods: In the course of crafting this narrative review, an exhaustive literature search was carried out. Our exploration spanned several renowned scientific databases, such as PubMed, Scopus, Web of Science, and ResearchGate. The materials we sourced for our review included a broad spectrum of both experimental and non-experimental articles, all focusing on TMG. The experimental articles featured varied research designs including randomized controlled trials, quasi-experiments, as well as pre-post studies. As for the non-experimental articles, they encompassed a mix of case-control, cross-sectional, and cohort studies. Importantly, all articles included in our review were written in English and had been published in peer-reviewed journals. The assortment of studies considered provided a holistic view of the existing body of knowledge on TMG, and formed the basis of our comprehensive narrative review. Results: A total of 34 studies were included in the review, organized into three sections: 1) assessing muscle contractile properties of young athletes, 2) using TMG in the talent identification and development process and 3) Future research and perspectives. According to data presented here, the most consistent TMG parameters for determining muscle contractile properties are radial muscle belly displacement, contraction time, and delay time. Biopsy findings from the vastus lateralis (VL) confirmed TMG as a valid tool for estimating the ratio of myosin heavy chain (%MHC-I). Conclusion: TMGs ability to estimate the ratio of %MHC-I has the potential to aid in the selection of athletes with the muscle characteristics best suited for a particular sport, eliminating the need for more invasive procedures. However, more research is warranted to fully understand TMG's potential and its reliability when used with young athletes. Importantly, the use of TMG technology in this process can positively impact health status, reducing the frequency and severity of injuries and the duration of recovery, and subsequently can reduce drop out rates among youth athletes. Future studies should look at twin youth athletes, as a model capable of discriminating between the influence of hereditary factors vs. environmental factors, in therms of muscle contractility and TMG's potential for instance.

Anthropometric variability of European taekwondo champions / Variabilidad antropométrica de los campeones europeos de taekwondo

SUMMARY: World Taekwondo (WT) as an Olympic sport gained much more attention than before, and there is a growing need for precise and specific profiles of successful taekwondo competitors. Aim of this investigation was to determine body composition, somatotype, and selected anthropometric parameters/indexes of elite taekwondo champions and medal winners on the most demanding taekwondo tournaments in the World. The sample for this research consisted of n=16 (n=4 male; n=12 female) elite taekwondo champions, n=8 juniors and n=8 seniors, who were European (n=13), and World (n=3) champions of European descent. Data was collected longitudinally for seven years since 2015. Obtained results revealed specific (absolute) phenotype of taekwondo champions, following: PI (11.50 female; 11.85 male), HWR (43.96 female; 44.47 male) and BMI (19.96 female; 22.04 male). Further analysis shows that champions have greater values of body height, and have slightly greater ectomorphy and mesomorphy values in regard to other elite competitors. Presented research is the first publication of referent values for the general anthropometric dataset, and such results represent the anthropometric variability of European WT champions.

World Taekwondo (TW) como deporte olímpico ha logrado una mayor importancia, y existe una creciente necesidad de contar con perfiles precisos y específicos de competidores exitosos de TW. El objetivo de esta investigación fue determinar la composición corporal, el somatotipo y parámetros/índices antropométricos seleccionados de campeones de TW de élite y los ganadores de medallas en los torneos de TW más exigentes del mundo. La muestra para esta investigación consistió en n=16 (n=4 hombres; n=12 mujeres) campeones de TW de élite, n=8 juniors y n=8 seniors, que eran europeos (n=13) y mundiales (n=3), campeones de ascendencia europea. Los datos se recopilaron longitudinalmente durante siete años desde 2015. Los resultados obtenidos revelaron un fenotipo específico (absoluto) de los campeones de TW, a continuación: PI (11,50 mujeres; 11,85 hombres), HWR (43,96 mujeres; 44,47 hombres) e IMC (19,96 mujeres; 22,04 hombres). Un análisis más detallado muestra que los campeones tienen mayores valores de altura corporal y tienen valores de ectomorfia y mesomorfia ligeramente mayores con respecto a otros competidores de élite. La investigación presentada es la primera publicación de valores de referencia para el conjunto de datos antropométricos generales, y dichos resultados representan la variabilidad antropométrica de los campeones europeos de TW.

True Strength of Ceramic Fiber Bundles: Experiments and Simulations.

A study on the strength of ceramic fiber bundles based on experimental and computational procedures is presented. Tests were performed on single filaments and bundles composed of two fibers with different nominal fiber counts. A method based on fiber rupture signals was developed to estimate the amount of filament rupture during the test. Through this method, the fiber bundle true strength was determined and its variation with the initial fiber count observed. By using different load-sharing models and the single filament data as input parameter, simulations were also developed to verify this behavior. Through different approaches between experiments and simulations, it was noted that the fiber bundle true strength increased with the fiber count. Moreover, a variation of the fibers' final proportion in the bundles relative to the initial amount was verified in both approaches. Finally, discussions on the influence of different load-sharing models on the results are presented.

A New Method for Biostatistical miRNA Pattern Recognition with Topological Properties of Visibility Graphs in 3D Space.

Visibility is a very important topic in computer graphics and especially in calculations of global illumination. Visibility determination, the process of deciding which surface can be seen from a certain point, has also problematic applications in biomedical engineering. The problem of visibility computation with mathematical tools can be presented as a visibility network. Instead of utilizing a 2D visibility network or graphs whose construction is well known, in this paper, a new method for the construction of 3D visibility graphs will be proposed. Drawing graphs as nodes connected by links in a 3D space is visually compelling but computationally difficult. Thus, the construction of 3D visibility graphs is highly complex and requires professional computers or supercomputers. A new method for optimizing the algorithm visibility network in a 3D space and a new method for quantifying the complexity of a network in DNA pattern recognition in biomedical engineering have been developed. Statistical methods have been used to calculate the topological properties of a visibility graph in pattern recognition. A new n-hyper hybrid method is also used for combining an intelligent neural network system for DNA pattern recognition with the topological properties of visibility networks of a 3D space and for evaluating its prospective use in the prediction of cancer.