Wyniki wyszukiwania - BazTech

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The influence of gender, dominant lower limb and type of target on the velocity of taekwon-do front kick

Wąsik J., Ortenburger D., Góra T., Shan G., Mosler D., Wodarski P., Michnik R. A.

Acta of Bioengineering and Biomechanics

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2018

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Vol. 20, no. 2

133--138

EN

Purpose: The current study aimed to quantify the main influences and the interactions (joint effects) of gender, leg and type of target on the biomechanics of front kick quality. Through the quantification, we tried to identify the relevant factors related to the kick accuracy and maximum velocity for coaching practice. Methods: A ten-camera NIR VICON MX40 motion capture system (250 Hz) was used to determine the kicking foot maximum velocity from two well-trained subject groups (8 males and 6 females). Each subject performed both left and right front kicks in a lateral standing position into the air (without a physical target), to a board, to a table tennis ball and to a training shield. The target were set on a height corresponding to a height of solar plexus of each participant. Results: The results showed that all the three factors (gender, leg and type of target) have significant influences on kicking speed ( p < 0.001) and significant interaction (joint effect) was only found between gender and target ( p < 0.001). Further analysis revealed that the males’ kicking maximum velocity was affected more by board, while females’ one was affected by the size of the target. Conclusions: The results would seem to suggest that, for males, kick-to-a-board may be the more effective method for increasing kick quality, compared to other type of target. For females, kick-to-a-small-ball appears to be effective method for increasing kick maximum velocity.

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Target effect on the kinematics of Taekwondo Roundhouse Kick – is the presence of a physical target a stimulus, influencing muscle-power generation?

Wąsik J., Shan G.

Acta of Bioengineering and Biomechanics

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2015

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Vol. 17, no. 4

115--120

EN

Taekwondo is famous for its powerful kicking techniques and the roundhouse kick is the most frequently used one. In earlier literature, the influence of a physical target (exiting or not) on kicking power generation has not been given much attention. Therefore, the aim of this study was to investigate the kinematics of roundhouse kick execution and its factors related to power generation. 6 ITF taekwondo practitioners voluntarily participated in this study. They were asked to perform kicks with and without a physical target. The first kick aimed at breaking a board while the second one was a kick into the air. A Smart-D motion capture system (BTS S.p.A., Italy) was used to quantitatively determine their kinematic characteristics during each kick. The main findings showed that kicks aiming at a breaking board were significantly slower than kicks without a physical target (maximal kick-foot velocities were 10.61 ± 0.86 m/s and 14.61 ± 0.67 m/s, respectively, p < 0.01), but the kicking time of the former was shorter (0.58 ± 0.01 s and 0.67 ± 0.01, respectively, p < 0.01). The results suggest that a physical target will negatively influence the kick-foot velocity, which is not necessarily a disadvantage for creating a high quality kick. Possible motor control mechanisms are discussed for the phenomenon. The study made it clear: trainings with and without physical targets would develop different motor control patterns. More studies are needed for identifying the effectiveness of different controls and efficiencies of their training.

3

Kinematic analysis of the side kick in Taekwon-do

Wąsik J.

Acta of Bioengineering and Biomechanics

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2011

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Vol. 13, no. 4

71-75

EN

The aim of the paper is to present the analysis of the influence of chosen kinetic factors on the side-kick technique. This issue is of a significant importance in the traditional version of Taekwon-do, where a single strike may reveal the winner. A male athlete, a black-belt holder, has participated in this case study. Generally accepted criteria of sports technique biomechanical analysis were adhered to. The athlete executed a side kick four times (in Taekwon-do terminology referred to as yop chagi) in a way most typical of his usual kick execution in board breaking. The parameter values obtained were used to determine the individual curves of the changes in velocities in the function of relative extension length of the kicking leg. The maximum knee and foot velocities in the Cartesian coordinate system were determined. The leg lifting time and the total time of kick execution as well as the maximum force which the foot exerted on the ground were also determined. On the basis of the values obtained the average values and the standard deviation were calculated. The correlation dependence (r = 0.97) shows that a higher knee velocity significantly affects the velocity which the foot develops and that the total time of kick execution depends on the velocity which the knee develops in the leg lifting phase (r = 0.75). The average maximum speed was obtained at the length of the leg equal to 82% of the maximum length of the fully extended leg. In the kicking technique used by the athlete, this length can be considered for this athlete the optimum value for achieving the maximum strike dynamics.

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Kierunki rozwoju organicznych ogniw słonecznych

Wróbel A., Wąsik J., Godlewski J.

Czysta Energia

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2010

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Nr 7-8

22-23

PL

Wykorzystanie energii słonecznej do bezpośredniego przetwarzania na energię elektryczną jest niezwykle interesującym zadaniem ze względu na ochronę środowiska oraz powszechną dostępność energii słonecznej.

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Elementy fizyki w treningu Taekwon-do

Wąsik J., Ślęzak A.

Prace Naukowe. Chemia / Wyższa Szkoła Pedagogiczna w Częstochowie

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2003

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Vol. 8

135--139

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Ciśnieniowy efekt stężeniowych warstw granicznych w jednomembranowej komórce osmotyczno-dyfuzyjnej

Ślęzak A., Wąsik J.

Prace Naukowe. Chemia / Wyższa Szkoła Pedagogiczna w Częstochowie

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2003

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Vol. 8

121--134

PL

Przedstawiono klasyfikację i definicje efektów stężeniowych warstw granicznych w biernym transporcie membranowym. Wyróżniono strumieniowe (strumieniowy efekt stężeniowych warstw granicznych, strumieniowy efekt grawidyfuzyjny, prądowy efekt grawielektryczny) i bodźcowe (ciśnieniowy efekt grawiosmotyczny, ciśnieniowy efekt grawidyfuzyjny, napięciowy efekt grawielektryczny) efekty grawitacyjne. Opracowano matematyczny model ciśnieniowego efektu stężeniowych warstw granicznych w 1-membranowej komórce osmotyczno-dyfuzyjnej zawierającej ustawioną poziomo płaską, mikroporowatą i symetryczną membranę polimerową (Nephrophane) rozdzielającą wodę i dwuskładnikowe (wodne roztwory glukozy) lub trójskładnikowe (roztwory glukozy w 0.2 mol.l-1 wodnym roztworze etanolu) roztwory nieelektrolitów. Obliczenia ciśnieniowego efektu stężeniowych warstw granicznych wykonano dla dwu konfiguracji (A i B) 1-membranowej komórki osmotyczno-dyfuzyjnej. W konfiguracji A roztwór znajdował się pod membraną, natomiast w konfiguracji B - nad membraną. Ponadto zdefiniowano i obliczono ciśnieniowy efekt grawiosmotyczny. Otrzymane rezultaty obliczeń zinterpretowano w kategoriach konwekcyjnej niestabilności, zwiększającej wartość współczynnika przepuszczalności dyfuzyjnej układu: warstwa graniczna/membrana/warstwa graniczna.

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Możliwości zwiększenia skuteczności odpylania i żywotności elektrofiltrów

Błaszczyk A., Wąsik J.

Energetyka

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1999

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nr 5

238-242