The purpose of this study was to explore and confirm Kumi-kata related factors of muscle strength by performance level in Korea elite female judoists. In order to achieve this purpose, 14 elite female judoists participated to this study. The subjects were divided to two groups (World Class Group and Non-World Class Group) according to their world ranking level(by ranked 30th). The analysis factors were repeated grip strength, Kumi-kata specific pulling strength and isokinetic strength of trunk joint. The results were as follows: Firstly, World Class Group had significantly higher repeated grip strength as compared to non-world class group (p<.001). Secondly, World Class Group had significantly higher specific Kumi-kata pulling strength as compare to non-world class group (p<.05). Finally, The differences between the two groups for isokinetic strength of trunk joint were non-significant. The results of this study indicates that a strong relationship exist between Kumi-kata related specific muscle strength and performance level in korea elite female judoists.
Purpose The purpose of this study was to examine athletes’ psychological competition experiences. Methods For this study, 64 student athletes, attending universities located in Seoul and Chungcheongbuk-do, participated in the study by completing an unconstructed questionnaire. The data were analysed through content analysis method. Results As a result, 15 themes, such as morale loss, comparable performance levels, opponent irritation were collected and the themes were classified into three categories including objectives of psychological competition, requirements of psychological competition, and psychological battle. In match situations, athletes attempt to psychologically compete in order to achieve objectives such as opponent’s morale loss, induce carelessness, trigger agitation and anger, dispersion of attention, and distraction. Psychological competition among rivals is valid when the requirements, such as comparable performance levels, sensitivity to match situations, strong tenacity and confidence, understanding of opponent and oneself, mutual checks and balances, are met. Athletes attack and defend to win the psychological competition by utilizing opponents irritation, information distortion, unexpected behaviors, predicting and coping, pulling a poker face, exclusion of opponents, and self-focusing. Conclusion This study created a theoretical foundation for a profound understanding of athletes’ psychological competition, which is often found in sport fields. Furthermore, this study is meaningful in that it has raised a chance of interest concerning psychological interaction between players in match situations.
[Purpose] Perception plays an important role in understanding the environment or related objects in order for humans to perform physical movements more effectively. Sometimes they create different movements with different perceptions. Especially, visual perception errors that occur in sports situations can have a considerable effect on performance. Accurate knowledge of the environment in this process of perception is important in performing movements or actions. The purpose of this study was to investigate the effect of learning formation on perception using Muller-Liar illusion diagrams. To measure this, we compared the feedback group that induced knowledge learning and the control group that did not provide knowledge To see if there is a difference. Therefore, in this study, we have provided a visual feedback that can establish the cognitive awareness of the actual stimuli length to subjects, and investigated the changes in their matching action responses. [Methods] A total of 32 young and healthy subjects were randomly divided into two groups (Feedback and Non-Feedback groups). Subjects were asked to match the stimulus size with their index fingers and thumbs. Initially (pre-test), three different visual stimuli (inward, outward, and no arrows) were randomly presented 60 times (20 times each) and the grip sizes were recorded using the Liberty Motion Analysis System (Polhemus Co., America). Then, video clips of two lines merging each other were presented as feedbacks. Post-test protocol was identical to the pre-test protocol. The data were analyzed using the 3-way ANOVA with one RM factor (2 x 3 x 2). [Results] Results showed a significant 2-way interaction effect. Post-hoc results showed significant interaction between stimulus shape and pre/post-tests only in the experimental group. There was a significant decrease in the grip size after feedback in the OUT condition of experimental group. However, in the control group, there was no interaction between stimulus shape and pre/post-tests. [Conclusion] Overall, current results indicates that, while visual illusion can affect the action, the provision of visual feedback can establish the awareness of actual stimulus size and suppress the influence of illusion on action.
