Comparison of Patterns of Skill Actions between Analog and Electronic Protectors in Taekwondo: A Log-Linear Analysis

The purpose of this study was to compare the patterns of skill actions executed during Taekwondo competitions when wearing and not wearing an electronic protector. To achieve this purpose, 110 matches from two university-level Taekwondo championships were taped and analyzed. The performance skills were composed of 18 detailed skills and grouped into five categories by considering kicks to the target area (chest or head/face). The data were organized in the form of a contingency table that demonstrated the relationship between grouping factors (skills, protectors, win-lose, and weight division). A log-linear analysis was carried out to investigate the effect of the grouping factors (IVs) on the skills (DV) using SPSS Statistics. The results obtained in the present study can be summarized as follows. First, the overall proportion of "points" called by the judge for the general protector (32.3%) was approximately 3.4 times that for the electronic protector (9.5%). Second, for the electronic protector, the proportions of kicks to the chest area were in the following order: Roundhouse kick (R-Kick) (44.7%), Pushing kick (P-kick) (19.3%), Turn kick (T-kick) (8.7%), and Double roundhouse kick (DR-kick) (7.6%). For the general protector, the order differed slightly, with T-kick and P-kick switched around with different proportions. Third, the proportion of kicks to the head/face was higher for the electronic protector (19.8%) than for the general protector (10.4%), and this difference was even more distinct when the light (-68kg) (33.5% (electronic) vs. 6.5% (general)) and heavy (+85kg) (1.4% (electronic) vs. 13.3% (general)) weight divisions were compared. Finally, the match status (win/lose) had no significant effect on the pattern of playing actions for both the protectors. The result from this study suggests that skill frequency of linear simple movement for activating electrical protector's sensor is increased, while the one of rotational complex movement is decreased gradually. Additionally, headgear without sensors, such as for a hit movement to the face/head part, represent characteristics of increased attack skills to the facial area; these scores are provided through subjective judgement, and consequently changes in performance skills can occur.