Caput‐Jogunica, R. et al.: Children achievements in composite measure… Acta Kinesiologica 3 (2009) 2: 38‐42 38 CHILDREN'S ACHIEVEMENTS IN COMPOSITE MEASUREMENT INSTRUMENTS FOR EXPLOSIVE STRENGTH Romana Caput-Jogunica¹, Sergio De Privitellio² and Darko Lončarić³ ¹ Faculty of Agriculture, University of Zagreb, Croatia ² Fitness Centar „Studio S“, Rijeka, Croatia ³ Faculty of Teacher Education, University of Rijeka, Croatia Original scientific paper Abstract A battery of the five composite motor tests for explosive strength suitable for preschool children aged five has been applied to a group of 180 participants in extracurricular sports program in four kindergartens in the city of Rijeka in Croatia. This experimental research has contributed to the results of previous research regarding the following; 1. The results in applied composite tests in the research have determined that the third performance of the task has achieved better results which lead to the conclusion that children learn how to perform the task during the first and second performance 2. Conducted analysis has confirmed good metric characteristics of examined motor tests for explosive strength in children aged 5 and 3. The applied battery of five composite motor tests concerning its metric characteristics could be implemented in the standardized battery of motor tests suitable for preschool children for monitoring children motor development as well as their achievements in motor abilities. Key words; children, explosive strength, composite motor test. Introduction Children show considerable increase in performance in skills between 5 and 8 years of age (running speed and shuttle run) and a steady, more gradual increase in performance in others from 5 years of age through childhood (e.g. jumping, throwing and strength). Controlling of learning effects is a significant logistic problem in longitudinal studies of motor performance; How much of the observed improvement reflects growth-related changes and how much reflects learning to perform the task? (Malina et al. 2004). Motor performance depends on muscular strength and according to the longitudinal studies strength improves linearly with age from early childhood. According to the analysis of the results from different research (Rajtmajer, 1990; Živčić and Hraski, 1995; Bala, 1999; 2003; Mišigoj-Duraković, 1999; Malina, 2004; Trajkovski-Višić, 2004;, Živčić et al. 2008; De Privitellio, 2006 and 2009) we can conclude the following; 1. Muscular strength increases gradually during early childhood and 2. Gender differences in average strength are small but consistently favour boys for running, jumping and throwing. According to Malina, 2004. gender differences in motor performance probably reflect the types of activities available to preschool children and motor skills of boys and girls at this young age as well as societal expectations for physical activity. The purpose of this research is to analyse one part of strength; the achievements in explosive strength motor tests, suitable for preschool children aged 5. The paper has been prepared as a pilot experimental research of the Master thesis on the Faculty of Kinesiology, University of Zagreb. The development of explosive strength has great influence on children's health, especially on child's skeleton. Furthermore, bone density structure during the youth period can determine the bone density in adulthood. Some of the main objectives for preschool aged children in process of developing of explosive strength are harmonious child's growth and development as well as child's well being and health. (Mišigoj – Duraković, 1999). According to Milanović (2008), the most appropriate physical activities for developing explosive strength are the basic motor movements such as walking, running, throwing as well as different elementary and sport games with low intensity and without extra weight. Concerning all the important scientific knowledge written above, the intention of this experimental research was to examine the battery of composite motor test for explosive strength which is characterized as high reliability and simplicity of movement, suitable for children considering their age, abilities and motor knowledge, safety and feasibility in all kindergartens on national level regarding necessary equipment.