Differences in Some Kinematic Parameters between Two Qualitatively Different Groups of Pole Vaulters.

The basic aim of this research was to determine the differences of kinematic parameters in two qualitatively different groups of young pole vaulters. With this purpose, a research was conducted in which the video records from a competition were acquired. The sample of entities (N = 71) consisted of successful vaults of 30 pole vaulters, whose attempts were recorded at the European Junior Championship in Novi Sad, held on 23-26th July 2009. The examinees performed the vaults as a part of the elimination competition for the finals, and during the final part of the competition. The age of examinees was from 17 to 19 years, and the span of their best results was from 4.70 to 5.30 meters. The kinematic analysis was conducted according to the standards of APAS procedure (Ariel Performance Analysis System, USA), determining 25 kinematic variables necessary for further analysis. The entities (vaults) were divided into two categories (qualitative classes) based on the expert knowledge. Group 1 consisted of successful vaults up to 4.90 m (N = 46), while group 2 consisted of successful vaults whose height was more than 4.90 m (N = 25). The discrimination analysis determined the parameters differentiating the vaults of different quantitative classes. Also, it was confirmed that the result efficiency in pole vault was primarily determined by the variables defined by motor abilities, as well as the indicators determining the vault performance technique.

Influence of kinematic parameters on pole vault results in top juniors.

The aim of this research was to analyse the kinematic parameters and to ascertain the influence of those parameters on the pole vault result. The entity sample of the research consisted of successful vaults of 30 athletes, whose attempts were recorded at the European Junior Athletics Championships. The examinees performed the vaults as part of the qualification competition for the finale and the finale of the competition itself The examinees were 17-19 years old, and the range of their top results was from 4.90 to 5.30 m. The results of the regression analysis showed a significant influence of the predictor variables on the effective pole vault height. The centre of body mass height was mostly influenced by the following variables: TS - takeoff velocity, LSS - last step velocity, PSS - penultimate step velocity, TAPR - trunk angle at the moment of the pole release. The following variables had lesser, but still a significant influence: CBMDM - centre of body mass distance at the pole release moment, and MCMVV - time of pole straightening. Generally, the information gained by this research indicates the significant influence of the kinematic parameters on the pole vault result. Therefore, the conclusion is that the result efficacy in the pole vault is primarily determined by the variables defined by the motor capabilities, but also by the indicators determining the vault activity realization technique. The variables that define the body position during the pole release (trunk angle and centre of mass distance) have heomost significant influence on the vault performance technique, while the motor capabilities influence the last two run up steps velocity, take off speed and the time of pole straightening.

The impact of specific motoricity on karate performance in young karateka.

The aim of the study was to assess interdependence of specific motor abilities (situation karate tests) and motor skills (karate techniques), and karate performance (fighting efficiency) in under-sixteen male karateka aged 11-12 and 13-14 years. A battery of 5 situation motor tests were applied and 6 basic elements of karate technique evaluated in a sample of 20 male karateka aged 11-12 and 20 male karateka aged 13-14 years. Three criterion variables were formed: 1) one factor as a factor of general technical efficiency in karate was isolated by factor analysis of 6 karate techniques; 2) cumulative evaluation of 2 kate as kate performance; and 3) total score assessment based on success achieved at national karate championships as contest efficiency (fighting efficiency). Regression analysis revealed the frequency of gedan barai blockade performance to be the superior predictor of technical efficiency, kate performance and contest success in karateka aged 11-12, whereas the speed of the gedan barai-jaku zuki (block-kick) combination performance and specific agility (sidewise mobility) were superior predictors of performance in karateka aged 13-14. Of the karate techniques (kicks) used, the quality of jaku zuki kick performance was the superior predictor of contest efficiency in karateka aged 11-12, and the quality of the jaku zuki-mawashi geri and kizame zuki-jaku zuki combination performance in karateka aged 13-14.

Sex differences in morphological dimensions in twelve-year-old children from Imotska krajina.

The aim of the study was to identify and compare morphological characteristics of 12-year-old male and female children from Imotska krajina. The structure of a set of 23 morphological space variables were determined in a sample of 75 male and 67 female children by use of factor analysis for each sex in separate. Factor structure showed two basic superior latent dimensions responsible for directly measurable manifestations of morphological parameters in both male and female children. One of these two dimensions behaved as a general mechanism of growth and development, whereas the other showed a bipolar pattern. Bipolarity was almost exclusively determined by adipose tissue on one pole, and by skeletal longitudinal growth on the opposite pole. Rotation of the main components to varimax position yielded two morphological dimensions that were well balanced in both sexes (slightly better in girls); besides the predominant increase in adipose tissue, one of these dimensions was also responsible for the development of muscular tissue and skeletal transverse development, whereas the other was responsible for skeletal transverse development and muscular tissue development in addition to the predominant longitudinal skeletal growth. These observations suggested two developmental processes, i.e. transverse morphological development (first factor) and longitudinal morphological development (second factor), to be almost equally involved in the morphological development of 12-year-old male and female children. These developmental processes are highly genetically determined and can only in part be explained by the intensity of kinesiologic engagement. Based on the morphological structures defined, discriminative function of the morphological space primarily differentiated two developmental processes, i.e. longitudinal skeletal development (hand length in particular) in female children relative to transverse skeletal development (knee diameter in particular) in male children, pointing to the presence of full-swing puberty in female children, while yet to be expected in male children; thereafter, the differences in the ectomesomorphic morphological characteristics would be by far more pronounced in favor of male children.

Development of motor and specific motor abilities for athletics in elementary school male and female first-graders.

The aim of the study was to determine canonic relations between the set of basic motor variables and the set of athletic variables assessing the abilities of sprint, throw and long-distance run adjusted for children aged seven years. Study sample consisted of 635 first-graders from Split elementary schools, divided into groups of 325 male and 310 female subjects. The set of nine variables of the basic motor space and three variables of situation motoricity in athletics were applied at the beginning and at the end of the academic year. Association between the sets of variables was determined by canonic correlation analysis. In male subjects, association between the sets of variables revealed a predominant effect of explosive strength on the sprint and throw ability on initial measurement. On final measurement, association in the first pair of canonic dimensions was underlain by the favorable impact of all strength factors with a predominance of explosive strength, which was accompanied by the development of flexibility and coordination, influencing performance in sprint and throwing; the second canonic variable was bipolar, differentiating aerobic endurance ability determined by above-average flexibility, frequency of lower extremity movements and static strength, and throwing ability determined by above-average equilibrium, explosive strength, coordination and repetitive strength. In female subjects, on initial measurement association in the first pair of canonic dimensions was mostly determined by the effect of explosive strength, repetitive strength of the trunk and movement frequency on general ability in athletics defined by the abilities of sprint, throw and long-distance run. Association in the second pair of canonic dimensions was determined by the impact of explosive strength and flexibility on sprint performance on the one hand, and by the effect of movement frequency and repetitive strength of the trunk on long-distance run performance on the other hand. In female subjects, final measurement yielded only one significant canonic correlation underlain by the impact of all strength factors, frequency of lower extremity movements and flexibility on performance in the athletic events of sprint and throw. Relations between the sets of variables are also discussed according to sex.