Jacek Wąsik

The structure and influence of different flying high front kick techniques on the achieved height on the example of taekwon-do athletes

Background The aim of this paper is to establish biomechanical optimization of the high-flying front kick (in taekwon-do terminology referred to as twimyo nopi ap chagi), which would result in developing a more effective method of executing this particular kick. Material/Methods: The study analysed movements of 14 ITF taekwon-do athletes (age: 16.5±0.7 years; weight 64.1±7.0 kg; height 176.5±4.6 cm). A system of complex analysis of movement called Smart-D made by the Italian company BTS Spa was used for the tests. For the purpose of the experimental part of the study the study participants were asked to adopt the same initial stance (in taekwon-do terminology called Niunja So Palmok Degi Maki) and perform the high-flying front kick in two different techniques – using the traditional technique (scissors) and the natural technique (non-scissors). Results: In case of the natural technique used for executing this kick the COG usually starts from the height of 0.9 m. After 0.5 sec. the COG is lowered by 0.1 m so that the athlete can take off having developed the required velocity. At the maximum height of the flight the COG reaches 1.54 m (having risen by 0.64 m), and this is the moment when the knee extension for kick completion occurs. In the traditional technique the COG is located at 0.9 m at the start and then lowers by 0.1 m. When leaping up at take-off the velocity increases immediately and at the flight maximum the COG reaches 1.46 m. This is also the height when the landing stage starts. The local maximum is marked at the height of 1.40 m, which corresponds to the moment of the knee extension needed to complete the kick. Conclusions: The observation shows that there are four main elements which influence the height achieved by an athlete in his jump and these include the height of the centre of gravity at take-off, the flight height of the COG as well as the height determined by the length of the lower limb and the angle formed between the plane perpendicular to the board and the limb. In the natural technique the athletes managed to raise their COG by an average of 74 mm higher than in the traditional technique (p<0.01).

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

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.

Physiotherapeutic Applications of Biomechanical Opposing Indicators – Based on Measurements of Taekwon-Do Athlets

Background. In everyday life people constantly face the dilemma of speed and accuracy. The aim of the cognitive quantification was to increase the knowledge about kinematic effect of a target. The practical aim would be to apply kinematic effect of a target in clinical situations, to supply for physiotherapeutic programs. Material and Method. The analysis was performed 14 taekwondo ITF athletes. During research they performed front left and right kicks in a lateral standing position: into the air (without a physical target), to a table tennis ball hanging on a line and a training target. The laboratory for the analysis of movement named HML was used here. Results. The highest average maximum velocity was obtained by the kicks without a physical target (10,78 - 1,32 m/s for men and 8,51 - 1,50 m/s for women)(p<0,05), then to the shield (9,98 - 1,40 m/s for men and 8,28 - 1,59 m/s for women) (p<0,05) and to the ball (9,63 -0,94 m/s for men 7,73 - 2,01 m/s for women) (p<0,05). Discussion.The obtained results provided the argument supporting the thesis that the type of target influences on the method of solving the dilemma: the velocity of movement and its precision during a frontal kick. Both, in the case of women and men who practisetaekwon-do, lowering the velocity of a kick, performed towards a precisely established target, in comparison with the velocity of a kick without a precisely established physical target (into the air) was observed. For many people with the dysfunctions of the movement organs, everyday functioning, especially related to movement, makes a challenge. In such a case crossing the road at the green light in particular time or stepping on the escalator (the examples of such barriers are numerous) are the tasks that reveal the dilemma of velocity and precision. There are many factors that may support the efficiency of these efforts. One of them may be the feeling of the efficiency of activity that has a psychological character.