Author(s): KOAKUTSU, A., YAO, N., CHIBA, G., HASEGAWA, N., Institution: NATIONAL DEFENSE ACADEMY OF JAPAN, Country: JAPAN, Abstract-ID: 576

Introduction
Tackling is an important part of the game in rugby football. It is also essential for coaches to grasp players’ cognitive structure of tackling. This study aims to develop a cognitive scale and demonstrate a structure of tackling for rugby football players.
Methods
This study used a questionnaire answered by 323 male rugby football players (101 high school students and 222 college students). The questionnaire consisted of 71 questions about tackling. The data collected was subjected to exploratory factor analysis, reliability analysis and confirmatory factor analysis by structural equation modeling.
Results
Five factors were extracted from the results using exploratory factor analysis. In the next exploratory factor analysis, the number of items of each factor is made equal, and each item was subordinated to each factor. The result also showed that each item had a factor loading amount over .40 and a simple structure. The Cronbach’s α of each factor was .79, .79, .76, .71 and .67, starting from factor 1. The fit coefficients by confirmatory factor analysis were sufficient (GFI=.937, AGFI=.903, CFI=.951, RMSEA=.056). All pass coefficients that observed variables from latent variables were significantly (p<.001) and showed positive values more than a medium level (.38−.89).
Discussion
The factors extracted by exploratory factor analysis were called Assertiveness, Sense of achievement, Fortune, Decision making, and Decisiveness. We judged that the scale was sufficiently reliable, because the Cronbach’s α was over .65. The result of confirmatory factor analysis showed sufficient construct validity of the model, which comprised of 15 items of the five factors. Rugby football player’s cognition of tackling consisted five factors. The resulting scale had sufficient reliability and validity, and we provided suggestions about using this scale.