Kinematic and electromyographic analyses of a karate punch

The aims of this study were: (i) to present the kinematic and electromyographic patterns of the choku-zuki punch performed by 18 experienced karatekas from the Portuguese team, and (ii) to compare it with the execution of 19 participants without any karate experience. The kinematic and electromyographic data were collected from the arm and forearm during the execution of the specific punch. A two-way analysis of variance (ANOVA) was used with significant level set at p</=0.05. We found that the kinematic and neuromuscular activity in this punch occurs within 400ms. Muscle activities and kinematic analysis presented a sequence of activation bracing a near-distal end, with the arm muscles showing greater intensity of activation than muscles in the forearm. In the skill performance, the arm, flexion and internal rotation, and the forearm extension and pronation movements were executed with smaller amplitude in the karate group. Based on the results of this study, the two groups' presented distinct kinematic and electromyographic patterns during the performance of the choku-zuki punch

Metabolic and energetics characterization and gender comparison in prepubertal karate practitioners

[EN] The number of children practicing karate is constantly increasing. It is necessary to provide correct information to the karate masters/coaches about this specific population, so they can properly developkarate training processes without causing any harm to practitioners but, on the contrary, contribute to theharmonious development of children and youths. This study was carried out with twenty-one prepubertal karate practitioners, male and female. They were analyzed on their maturational development, metabolic and energetic behavior in an incremental test until exhaustion. Only the energetic variables presented significant differences between gender, so it seems that the karate practice has a similar metabolic impact in the development of the prepubertal karate practitioners of both genders

Estudio exploratorio sobre maduración y nivel de competición en jóvenes practicantes de karate

[ES] El establecimiento de categorías en competiciones de jóvenes mejora las posibilidades de éxito y reduce las lesiones en el deporte. A pesar de que existen diferencias de maduración, la edad cronológica sigue siendo el criterio principal para igualar los niveles de competición, lo cual tiene una eficiencia limitada. En karate, el peso también se utiliza para agrupar atletas. Hemos investigado si existe asociación entre la edad cronológica y los indicadores de maduración y si es posible encontrar modelos sencillos que permitan plantear nuevas formas para evaluarla. Se recogieron datos de 54 jóvenes practicantes de karate (edad: 12,67 ± 2,49 años; experiencia: 4,99 ± 2,44 años, altura: 150,45 ± 15,25 cm, peso: 43,09 ± 14,17 kg, 20 niñas). La edad se correlacionó significativamente con la auto-observación de la maduración sexual (rho = 0,838, p < 0,01). Se encontraron modelos de regresión sencillos, utilizando variables como la altura, peso y perímetro del brazo, que explican moderadamente la maduración. Estos resultados deben hacer reflexionar a las entidades competentes sobre cómo agrupar a los atletas en las competiciones de manera justa en términos de maduración.[EN] Paring children improve the chance for success and reduce injury in sport. Despite the maturity differences between children, chronological age remains the main criterion to equalize competition levels, but with limited efficiency. However, in Karate, weight is also considered. We went to investigate the association between chronological age and maturational indicators and find simple models to put on reflection new ways to assess the maturity. Data were collected in 54 young Karate practitioners (age: 12.67 ± 2.49 years, experience: 4.99 ± 2.44 years, height: 150.45 ± 15.25 cm, weight: 43.09 ± 14, 17 kg, 20 girls). Age correlated significantly with self-observation of sexual maturation (rho = 0.838; p< 0.01), and it was possible to find simple regression models that have a moderate explanation in maturation, using only simple measurable variables such as the height, weight and arm circumference. These results should lead the competent entities to reflect on the way of pairing of the athletes in the competitions, in a fair way in terms of maturation.[PT] Emparelhar crianças propicia sucesso e reduz lesões no desporto. Apesar das diferenças de maturação entre crianças, a idade cronológica mantém-se o principal critério para equalizar os níveis de competição, mas com uma eficiência limitada. No entanto, no karaté, o peso também é considerado. Fomos verificar se existe associação entre a idade cronológica e os indicadores maturacionais e, encontrar modelos simples que permitam colocar em reflexão novas formas de avaliação da maturação. Foram recolhidos dados em 54 jovens praticantes de karaté (idade: 12,67± 2,49anos; experiência: 4,99 ± 2,44 anos; altura: 150,45 ± 15,25cm; peso: 43,09± 14,17 kg, 20 raparigas). A idade correlacionou-se significativamente com auto-observação da maturação sexual (rho = 0,838;p < 0,01), e foi possível encontrar modelos de regressão simples que têm uma explicação moderada na maturação, apenas utilizando variáveis de medição simples, tal como a altura, o peso e o perímetro do braço. Estes resultados devem levar as entidades competentes a refletir acerca do modo de emparelhamento dos atletas nas competições de uma forma justa em termos de maturação

Caracterización de los patrones cinesiológicos de la patada frontal, mae­-geri, en practicantes expertos de kárate y en sujetos no practicantes

[ES] Actualmente, los entrenadores e investigadores necesitan comprender bien los parámetros cinesiológicos del movimiento ya que son una herramienta importante de soporte de las metodologías de entrenamiento y enseñanza, y para mejorar el rendimiento de los gestos motores. El objetivo de este estudio fue (i) identificar los patrones cinemáticos y del control neuromuscular de ejecución de la patada frontal (mae­geri) en un objetivo fijo, realizada por 14 karatecas cinturón negro, (ii) y comparar con la ejecución del mismo gesto técnico realizada por 16 participantes sin práctica o experiencia en kárate, siendo posible el uso de esos datos en análisis del entrenamiento y del proceso de aprendizaje del kárate. Se verificó que la actividad cinemática y neuromuscular de ejecución de esta patada sucede en un espacio temporal de 600ms. La actividad muscular y cinemática evidencia la existencia de una norma secuencial temporal de intervención segmentar con un sentido próximo‐distal, donde los músculos estudiados tienen dos momentos distintos de actividad (períodos 1, 2). En el análisis electromiográfico (EMG), el grupo de karatekas presenta una mayor intensidad de activación (root mean square – RMS) y de pico de actividad en el músculo RectusFemoris (RF1) y VastusLateralis (VL1), y menor tiempo de contracción en ambos períodos en las relaciones entre los músculos RectusFemoris‐BicepsFemoris e VastusLateralis‐BicepsFemoris.En la realización de esta acción motora, los movimientos segmentares de flexión de muslo, de extensión de la pierna y de flexión plantar del tobillo fueron realizados con menor amplitud angular (range of action – ROA) por los karatekas, reflejando diferentes posicionamientos de los segmentos entre grupos. En conclusión, existe un patrón cinesiológico general, semejante entre practicantes y no practicantes de kárate. En el grupo de karatecas el entrenamiento induce una especialización de la actividad muscular, reflejada en los resultados del EMG y de la cinemática de movimiento, produciendo una mejor acción balística en la ejecución del mae­geri, que en asociación con una velocidad máxima de los segmentos distales, alcanzada cerca del momento del impacto, puede traducirse en un impacto más potente.[EN] Presently, coaches and researchers need to have a better comprehension of the kinesiological parameters that should be an important tool to support teaching methodologies and to improve skills performance in sports. The aim of this study was to (i) identify the kinematic and neuromuscular control patterns of the front kick (mae­geri) to a fixed target performed by 14 experienced karate practitioners, and (ii) compare it with the execution of 16 participants without any karate experience, allowing the use of those references in the analysis of the training and learning process. Results showed that the kinematic and neuromuscular activity during the kick performance occurs within 600 ms. Muscle activity and kinematic analysis demonstrated a sequence of activation bracing a proximal‐to‐distal direction, with the muscles presenting two distinct periods of activity (1, 2), where the karateka group has a greater intensity of activation – root mean square (RMS) and electromyography (EMG) peak – in the first period on RectusFemoris (RF1) and VastusLateralis(VL1) and a lower duration of co‐contraction in both periods onRectusFemoris‐BicepsFemoris and VastusLateralis‐BicepsFemoris (RF‐BF; VL‐BF). In the skill performance, the hip flexion, the knee extension and the ankle plantar flexion movements were executed with smaller difference in the range of action (ROA) in the karateka group, reflecting different positions of the segments. In conclusion, it was observed a general kinesiological pattern, which was similar in karateka and non‐karateka practitioners. However, in the karateka group, the training induces a specialization in the muscle activity reflected in EMG and kinematic data, which leads to a better ballistic performance in the execution of the mae­gerikick, associated with a maximum speed of the distal segments, reached closer to the impact moment, possibly representing more power in the contact.[PT] Actualmente, treinadores e investigadores necessitam de compreender bem os parâmetros cinesiológicos do movimento porque são uma ferramenta importante de suporte das metodologias de treino e ensino, e para melhorar a performance dos gestos motores. O objective deste estudo foi (i) identificar os padrões cinemáticos e de controlo neuromuscular da execução do pontapé frontal (mae­geri) num alvo fixo e realizado por 14 karatecas cinto negro, (ii) e comparar com a execução do mesmo gesto técnico realizada por 16 participantes sem qualquer prática ou experiência de karate, tornando possível o uso desses dados na analise do treino e do processo de aprendizagem do karate. Verificou‐se que a actividade cinemática e neuromuscular na execução deste pontapé acontece num espaço temporal de 600ms. A actividade muscular e cinemática evidencia a existência de um padrão sequencial temporal de intervenção segmentar com um sentido próximo‐distal, onde os músculos estudados têm dois distintos momentos de actividade (períodos 1, 2). Na análise electromiografia (EMG), o grupo de karatecas apresenta uma maior intensidade de activação (rootmeansquare– RMS) e de pico de actividade no musculo RectusFemoris (RF1) eVastusLateralis (VL1), e menor tempo de cocontração em ambos os períodos nas relações entre os músculos RectusFemoris‐ BicepsFemorise VastusLateralis‐ BicepsFemoris.Na realização desta acção motora, os movimentos segmentares de flexão da coxa, de extensão da perna e de flexão plantar do tornozelo foram realizados com menor amplitude angular (range of action – ROA) pelos karatecas, reflectindo diferentes posicionamentos dos segmentos entre grupos. Em conclusão, existe um padrão cinesiológico geral, semelhante entre praticantes de karate e não praticantes de karate. Todavia, no grupo de karatecas o treino induz uma especialização da actividade muscular, reflectida pelos resultados do EMG e da cinemática do movimento, o que conduz a uma melhor acção balística na execução do mae­geri, em associação com um máximo de velocidade dos segmentos distais, alcançado próximo do instante do impacto, o que poderá traduzir‐se num impacto mais potente

Characterization of kinesiological patterns of the frontal kick, mae-geri, in karate experts and non-karate practitioners

Presently, coaches and researchers need to have a better comprehension of the kinesiological parameters that should be an important tool to support teaching methodologies and to improve skills performance in sports. The aim of this study was to (i) identify the kinematic and neuromuscular control patterns of the front kick (mae-geri) to a fixed target performed by 14 experienced karate practitioners, and (ii) compare it with the execution of 16 participants without any karate experience, allowing the use of those references in the analysis of the training and learning process. Results showed that the kinematic and neuromuscular activity during the kick performance occurs within 600 ms. Muscle activity and kinematic analysis demonstrated a sequence of activation bracing a proximal-to-distal direction, with the muscles presenting two distinct periods of activity (1, 2), where the karateka group has a greater intensity of activation – root mean square (RMS) and electromyography (EMG) peak – in the first period on Rectus Femoris (RF1) and  Vastus Lateralis (VL1) and a lower duration of co-contraction in both periods on Rectus Femoris-Biceps Femoris and Vastus Lateralis-Biceps Femoris (RF-BF; VL-BF). In the skill performance, the hip flexion, the knee extension and the ankle plantar flexion movements were executed with smaller difference in the range of action (ROA) in the karateka group, reflecting different positions of the segments. In conclusion, it was observed a general kinesiological pattern, which was similar in karateka and non-karateka practitioners. However, in the karateka group, the training induces a specialization in the muscle activity reflected in EMG and kinematic data, which leads to a better ballistic performance in the execution of the mae-geri kick, associated with a maximum speed of the distal segments, reached closer to the impact moment, possibly representing more power in the contact

An analysis of the three-dimensional kinetics and kinematics of maximal effort punches among amateur boxers.

This is an Accepted Manuscript of an article published by Taylor & Francis in International Journal of Performance Analysis in Sport on 27-9-18, available online: https://doi.org/10.1080/24748668.2018.1525651The purpose of this study was to quantify the 3D kinetics and kinematics of six punch types among amateur boxers. Fifteen males (age: 24.9 ± 4.2 years; stature: 1.78 ± 0.1 m; body mass: 75.3 ± 13.4 kg; boxing experience: 6.3 ± 2.8 years) performed maximal effort punches against a suspended punch bag during which upper body kinematics were assessed via a 3D motion capture system, and ground reaction forces (GRF) of the lead and rear legs via two force plates. For all variables except elbowjoint angular velocity, analysis revealed significant (P < 0.05) differences between straight, hook and uppercut punches. The lead hook exhibited the greatest peak fist velocity (11.95 ± 1.84 m/s), the jab the shortest delivery time (405 ± 0.15 ms), the rear uppercut the greatest shoulder-joint angular velocity (1069.8 ± 104.5°/s), and the lead uppercut the greatest elbow angular velocity (651.0 ± 357.5°/s). Peak resultant GRF differed significantly (P < 0.05) between rear and lead legs for the jab punch only. Whilst these findings provide novel descriptive data for coaches and boxers, future research should examine if physical and physiological capabilities relate to the key biomechanical qualities associated with maximal punching performance

Metabolic and energetics characterization and gender comparison in prepubertal karate practitioners

The number of children practicing karate is constantly increasing. It is necessary to provide correct information to the karate masters/coaches about this specific population, so they can properly develop karate training processes without causing any harm to practitioners but, on the contrary, contribute to the harmonious development of children and youths. This study was carried out with twenty-one prepubertal karate practitioners, male and female. They were analyzed on their maturational development, metabolic and energetic behavior in an incremental test until exhaustion. Only the energetic variables presented significant differences between gender, so it seems that the karate practice has a similar metabolic impact in the development of the prepubertal karate practitioners of both genders.info:eu-repo/semantics/publishedVersio

Skin Landscapes : Touch as a pathway to care

This paper journeys through skin and touch as a form of storytelling and ritualistic bodily expression. It investigates how these elements and actions with the body can support humans in forging deeper connections and function as a catalyst for care. This work builds on theories of slow design, ritual design and Body-Mind Centering. It studies embodied research within design and shares insights gained through experiential and explorative practices. Further it looks at the human nature bond within female bodies as a a way to strengthen women and dismantle patriarchal structures. To conclude it explores how a booklet can be a medium for guiding women into their own bodies and invoking care with the self, other humans and more than human others