Full-text resources of PSJD and other databases are now available in the new Library of Science.
Visit https://bibliotekanauki.pl
Preferences help
enabled [disable] Abstract
Number of results

Results found: 3

Number of results on page
first rewind previous Page / 1 next fast forward last

Search results

Search:
in the keywords:  movement analysis
help Sort By:

help Limit search:
first rewind previous Page / 1 next fast forward last
1
Content available remote

Kinematics and Kinetics of Taekwon-do Side Kick

100%
EN
The aim of the paper is to present an analysis of the influence of selected kinematic factors on the side kick technique. This issue is especially important in the traditional version of taekwon-do, in which a single strike may reveal the winner. Six taekwon-do (International Taekwon-do Federation) athletes were asked to participate in this case study. Generally accepted criteria of sports technique biomechanical analysis were adhered to. The athletes executed a side kick three times (in Taekwon-do terminology referred to as yop chagi) in a way which they use the kick in board breaking. The obtained data were used to determine the mean velocity changes 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 duration of kick execution as well as the maximum force which the standing foot exerted on the ground were also determined. On the basis of the obtained values, mean values and standard deviations were calculated. The correlation dependence (r=0.72) shows that greater knee velocity affects the velocity which the foot develops as well as the fact that the total time of kick execution depends on the velocity which the knee (r = -0.59) and the foot (r = -0.86) develop in the leg lifting phase. The average maximum speed was obtained at the length of the leg equal to 82% of the maximum length of the fully extended leg. This length can be considered the optimum value for achieving the maximum dynamics of the kick.
EN
Introduction: Start performance in swimming plays a major role in determining the final standings, especially in sprint races. The purpose of the study was to determine kinematic parameters underlying the kick start from OSB12 in terms of the kick plate position and shoulder positioning at the start. Material and methods: The sample included 8 non-randomly recruited performance-level swimmers whose average age, body height, and body weight was 17.4 ± 1.8 years, 182.2 ± 3.4 cm and 81.00 ± 3.9 kg, respectively. To measure the kinematic parameters, we used the SwimPro camera system. The parameter rs measured included angular parameters and kinematic parameters for each of the start phases: block phase, flight phase, and water phase. We processed the collected biomechanical data using the Statistica 12.0 software. To determine significant differences between the kick plate positions in three types of start, we applied the Mann-Whitney U test. Results: We found significant differences (p<0.05) in the selected kinematic parameters in all phases, which depended on the OSB12 kick plate position and basic starting position (front-, neutral-, and rear-weighted). The greatest differences in the parameters measured were found between the front-weighted start and rearweighted start. We may conclude that performance-level swimmers should adjust the rear kick plate to positions 3 and 4 and assume the following starting position: front knee angle between 131° and 133°, rear knee angle around 80°, and trunk angle between 40° and 41°. This starting position affects the flight phase, namely takeoff angle (40⁰-41⁰), head position at takeoff (1.33-1.38 m), flight time and distance (0.346-0.368 s; 2.74-2.79 m), entry angle (38⁰). The starting position also affects the glide phase, namely the glide time and distance (0.532-0.536 s; 2.22-2.26 m) and maximum depth (-0.91-0.92 m). Conclusions: The results of the study show that swimmers produced shorter times to 5 meters and higher velocity at 5 meters compared with other starting positions and OSB12 kick plate positions.
EN
Velocity and accuracy of strike are important factors that help in achieving victory. The question is if the target selection can have an impact on the strike kinematics. The topic is especially important in the case of the traditional taekwon-do, in which a single kick might decide who the winner is. The aim of the paper is knowledge about the influence of the target on the kinematic factors of the front kick technique. In this study, a Polish Taekwon-do Championship runner-up was examined. The taekwon-do athlete (age: 28 years; body mass: 68 kg; height: 172 cm) is holding a 2nd degree, Motion analysis and data processing was prepared in HML (Human Motion Lab) using 10 NIR Vicon MX-T40 cameras with the acquisition speed of 100 to 2000 frames per second at full frame resolution of 4 megapixels. During the research various measurements were collected to perform dimensional analysis of foot and knee movement, describing their velocity changes as a function of time. The following strike speeds were recorded. No physical target: dominant leg foot 12.25 ± 0.18 m/s, non-dominant leg foot 13,92 ± 0,87 m/s. Small ball target/Punching ball: dominant leg foot 10,27 ± 0,29 m/s, non-dominant leg foot 10,03 ± 0,15 m/s. Kicking Shield/Shield: dominant leg foot 11,17 ± 0,34 m/s, non-dominant leg foot 10,06 ± 0,46 m/s. The quickest strike was registered when the athlete had no physical target in front of him. No focus on the target caused the fastest results. The shield target provoked a stronger and slower strike, as the speed has been slightly slower than in the non-target situation. The velocity of the foot was reduced the most when the most precision was needed. Aiming into a little ball caused the biggest speed to decrease the most. The main conclusion is that the more precision is needed, the more speed decrease will be observed
first rewind previous Page / 1 next fast forward last
JavaScript is turned off in your web browser. Turn it on to take full advantage of this site, then refresh the page.