Predictive validity of morphological and motor variables for the evaluation and monitoring of the karate free kata performance

Abstract

A system of 25 dependent variables, and 1 criterion variable, were analysed in 82 karate-practicing boys aged 10-14. There were 12 morphological variables, 12 basic motor skills variables, and the free kata performance as the only criterion variable. The purpose of this study was to determine specific influences of morphological and basic motor variables' systems on the criterion variable (free kata performance), and also to create a battery of instruments for the diagnostics, evaluation, monitoring, and assessment of the free kata performance based on this prediction model, via the regression analysis and stepwise statistics. The results demonstrated that the multi-variable predictive system of morphological variables did not have a statistically significant influence on the criterion variable (free kata performance)(p=.08). However, following stepwise method procedures, the influence was indeed significant (p=.00), as it was for basic motor variables (p=.00). From the reduced system of morphological variables, arm skinfold (p=.00), chest girth (p=.03), and leg length (p=.04) had the highest and statistically significant predictive validity (univariate). Within the reduced system of basic motor variables, it was shown that standing broad jump (p=.00), foot tapping (p=.01), 20m dash (p=.02), deep forward bend on the bench (p=.03), and situps in 30sec (p=.04) had the highest and the most significant predictive validity for the free kata performance. Based on these findings, the following test battery for the diagnostics, evaluation, monitoring, and assessment of the free kata performance may be constructed: upper-arm skinfold, chest girth, leg length, standing broad jump, foot tapping, 20m dash, deep forward bend on the bench, and sit-ups in 30sec.