Predictor validity of morphological and basic motor variables for assessment and monitoring of the karate punch with the lead arm (oi-tsuki)

Abstract

The purpose of this study was to determine the influence of morphological and basic motor variables on the karate forward punch (oi tsuki) as the only criterion variable, and secondly, to design a test battery for the assessment and monitoring of boys in karate, based on the predictive validity of the tested variables. A system of 25 variables in total - 12 morphological, 12 basic motor (the system of predictor variables) and 1 variable of situational moving structure (criterion variable), i.e. the karate punch with the lead arm (oi-tsuki) - was applied on a sample of 82 karate trainees aged between 10 and 14. The results of regression analysis showed that a system of morphological and basic motor variables had a significant impact on punching with the lead arm (p<0.01). The stepwise method identified the largest individual value in the case of morphological variables of arm length, upper arm skinfold and body mass at the level of significance p<0.01, whereas basic motor variables (long jump from a standing start and half squat with weight) also have a level of significance p<0.01. This shows that respondents with longer arms, less subcutaneous fat tissue on the upper arm, higher body mass and greater static and explosive strength of the lower extremities achieve better results. Determining predictor validity by regression analysis and the stepwise method is employed in order to diagnose, assess, monitor and evaluate the direct punch with the lead arm, so the next battery of measurement instruments can be constructed: arm length, upper arm skinfold, body mass, half squat with weight, long jump from a standing position.