THE RELATIONSHIPS BETWEEN ANTHROPOMOTORIC BODY DIMENSIONS AND THE FORCE - TIME STRUCTURE OF THE VERTICAL JUMP

INTRODUCTION: The take - off activities are quite various and many of their modifications are used in sport. The final result of the jump is influenced by a great variety of factors such as the quality of produced muscle strength timing of the jump, range of movement, arm activities etc. The basic determinants of many movement activities are the body dimensions (length and mass variables). This paper is focused on the questions concerning the relationship between the forcetime structure of the vertical jump (time, distance, velocity, force, final results) and the body dimensions. METHODS: The counter-movement vertical jump (CMJ) with an arm swing was registered on a KISTLER platform. The reaction force Fz (t) was analysed on an ON-LINE system using software developed in our lab. 23 variables describing the structure of CMJ from the point of view of time, distance, velocity of the centre of mass (CM), and produced force were computed in real time. Eleven values of body dimensions were measured for each subject (length variables of the lower limbs, body height, mass, width of knee, and ankle). The subjects of this research were two groups of students of physical education (men, n=54, age: 18 - 20 years, height: 178.40 ± 6.12cm, body mass: 79.00 ± 6.36 kg; women, n=47, height: 168.48 ± 6.20 cm, body mass: 59.77 ± 6.44 kg). Correlation and factor analysis (STATGRAPHICS package) were used for the statistical analysis. RESULTS: The factor analysis of eleven anthropometric values showed two groups of dependent variables (length parameters and body height - 1st factor, and body mass and width variables - 2nd factor). The three factor model of the CMJ structure selected three groups of dependent variables for both the men and women (1st - time and distance variables, 2nd - impulse momentum and variables of the final results of CMJ, 3rd - variables of the preparatory phase of the CMJ). The factor analysis of body dimension and CMJ variables has shown that the body dimensions are an independent group of variables and that they do not have a relationship to the CMJ structure. CONCLUSION: Factor analysis confirms the relative independence of the three groups of CMJ variables (time and distance, impulse momentum and final variables of the CMJ, the preparatory phase variables). The set of body dimension parameters does not have a relationship to the structure of CMJ. This finding was the same for both groups of men and women

THE INFLUENCE OF BODY HEIGHT ON THE SERVE IN TENNIS

A theoretical model expressing the relationship between the dimensions of the tennis court and the height at which the ball is stroked when served is the starting point for a study of the influence of the body height of a player on the serve in tennis. A model of the flight of the ball expressed as a straight line has provided us with the theoretical information we need at the beginning regarding the angle of the serve and the active distance of the impact of the ball as dependent on the height at which the ball is stroked. The characteristics of the model were confronted with the real values acquired in a kinematic analysis of the first and second serves of two top world-class players. An increase in the height of a player appears to be a dominant factor which positively influences the direction of the flight of the ball and the speed of the serve

A LONGITUDINAL STUDY OF INTRA-INDIVIDUAL VARIABILITY IN THE EXECUTION OF THE IN-RUN POSITION IN SKI JUMPING

INTRODUCTION: The change of flight in ski jumping (V-style) has influenced a change in the take-off process. When considering this fact, it is necessary to determine whether the same applies to the in-run position – one of the basic phases of ski jumping. The ski jumper must master three basic tasks of the in-run position: maintenance of equilibrium, acquisition of maximum approach velocity and preparation for take-off. The main goal of this paper was to determine whether a set of various models of the in-run position exists for selected competitors. METHODS: Data for this study were collected from the Intersport tournee Innsbruck between 1992 and 1998 at a distance of 18 m prior to the edge of the jumping hill. A 2D kinematic analysis was used to evaluate the in-run position of the ski jumpers (500 analyses). The in-run position was evaluated using eight angle parameters. Jumpers were chosen from among the competitors who jumped at least four times in this event. Assessments of inter-individual and intraindividual variability were made. For analysis of the results, a computer statistical package ‘Statgraphics’ (one-way analysis of variance, Kruskal-Wallis one-way analysis by ranks, cluster analysis) was used. RESULTS: A large range for the analyzed angles existed for the group of selected competitors. The changes occurring among the selected segments of the body varied with each individual sportsman. The athletes under study could be divided into several qualitative groups: high stability of the lower extremities position (subjects 1 and 2), high stability of the upper extremities position (subject 3), high stability of the lower extremities with regard to the trunk position (subjects 4 and 5), in-run position with low stability (subject 6), etc. The position of the center of gravity for subjects 1, 4, 7, 8 and 9 was often stable even with high variability of the other parameters. The data supported the concept that the influence of anthropometric and physiological characteristics is very important. CONCLUSIONS: Changes in the in-run position were found in all ski jumpers in the period between 1992 and 1998. Statistically significant differences (interindividual variability) existed among years of measurement. Within the group of selected ski jumpers the execution of the in-run position varied for both body position and the position of the segments of the body. There existed an individual solution of this movement situation for most ski jumpers – it can be called an individualized model of the in-run position

KINEMATIC ANALYSIS OF 100M HURDLE RACE IN FIRE SPORT

Fire sport is a discipline based on maximal movement velocity and optimal muscle-nerve co-ordination during the implementation of supporting movement activity. One of the most attractive disciplines is the 100m running event with various hurdles. The conclusive moment for passing a beam-hurdle is the way of starting towards the board. For analysis of this activity we used four video cameras and photocells to measure time parameters. According to efficiency we divided the monitored file (n=22, average age 24.37 years) into three groups. There is a trend, in order to maintain the velocity in the group of the best runners during the start, towards getting over the hurdle by executing the take off from the board is managed from a more forward position. In subjects with lowest efficiency there is a lowering of the ankle position during the runner’s contact with a rising board manifested via the braking rate

Udruženost višestrukih moždanih aneurizma i moždane arteriovenske malformacije: prikaz slučaja i pregled literature

The incidence of aneurysmal subarachnoid hemorrhage is about 10-11 cases per 100,000 inhabitants. The true incidence of multiple aneurysms is not known, however, according to previous studies it may vary between 20% and 30%. The association of arteriovenous malformation and cerebral aneurysm is well documented and varies between 20% and 30%. A case is described of a 47-year-old female presenting with massive acute subarachnoid hemorrhage. Computed tomography and cerebral panangiography revealed seven saccular aneurysms (five along the left anterior cerebral artery and its branches, one at the left M1/2 junction, and one in the anterior communicating artery), and an arteriovenous malformation involving the left frontal and parietal lobe fed mostly by the left anterior cerebral artery. Neurosurgeons clipped all seven aneurysms and then the arteriovenous malformation was extirpated.Incidencija aneurizmatskog subarahnoidnog krvarenja iznosi oko 10-11 slučajeva na 100.000 stanovnika. Stvarna incidencija višestrukih aneurizma nije poznata, no prema prethodnim ispitivanjima ona bi se mogla kretati između 20% i 30%. Udruženost arteriovenske malformacije i moždane aneurizme dobro je dokumentirana i kreće se između 20% i 30%. Autori izvješćuju o slučaju 47-godišnje žene koja je dola s opsežnim akutnim subarahnoidnim krvarenjem. Kompjutorizirana tomografija i cerebralna panangiografija otkrile su sedam sakularnih aneurizma (pet duž lijeve prednje moždane arterije i njezinih ogranaka, jednu na lijevom spoju M1/2 i jednu u prednjoj komunikacijskoj arteriji) i arteriovensku malformaciju koja je zahvaćala lijevi frontalni i parijetalni režanj koji se uglavnom opskrbljuje putem lijeve prednje moždane arterije. Neurokirurzi su štipaljkama učvrstili svih sedam aneurizama, nakon čega je uklonjena arteriovenska malformacija

Discrimination of resected glioma tissues using surface enhanced Raman spectroscopy and Au@ZrO2 plasmonic nanosensor

Gliomas present one of the most prevalent malignant tumors related to the central nervous system. Surgical extraction is still a preferred route for glioma treatment. Nonetheless, neurosurgeons still have a considerable challenge to detect actual margins of the targeted glioma intraoperatively and correctly because of its great natural infiltration. Here we evaluated the possibility of using surface-enhanced Raman spectroscopy to analyze freshly resected brain tissues. The developed method is based on the application of Au@ZrO2 nanosensor. The plasmonic properties of the sensor were first tested on the analysis of Rhodamine 6G, where concentrations down to 10-7 mol/L can be successfully detected. We also compared the performance of the nanosensor with silver plasmonic nanoparticles, where similar results were obtained regarding the reduction of the fluorescence background and enhancement of the intensity of the measured analytical signal. However, application of silver nanospheres led to increased variations in spectral data due to its probable aggregation. Applied ZrO2@Au nanosensor thus dramatically lowers the fluorescence present in the Raman data, and considerably improves the quality of the measured signal. The developed method allows for rapid discrimination between the glioma's periphery and central parts, which could serve as a steppingstone toward highly precise neurosurgery.H2020 WIDESPREAD-2020-5, (952063); NANO4TARMED consortium; National Cancer Research Institute, NCRI, (LX22NPO5102); European Commission, EC; Ministerstvo Školství, Mládeže a Tělovýchovy, MŠMT; Ministerstvo Zdravotnictví Ceské Republiky, MZCR, (NV19-04-00281)Ministry of Health of the Czech Republic [NV19-04-00281]; NANO4TARMED consortium (H2020 WIDESPREAD-2020-5) [952063]; MEYS CR [LM2018129]; National Institute for Cancer Research (Programme EXCELES) - European Union-Next Generation EU [LX22NPO5102

MICROCOMPUTER SYSTEM (VariaCardio TF4) DESIGNED FOR THE DIAGNOSTICS OF HEART RATE VARIABILITY DURING HUMAN MOVEMENT

INTRODUCTION: One of many possibilities of controlling the intensity of sport training and the responses of an athlete to an exercise load is through the regulation of heart rate (HR) values or the evaluation of heart rate variability (HRV). While the HR diagnostics can be realized with the help of several devices (e.g. SPORTESTER - POLAR ELEKTRO, Finland), the evaluation of HRV, using spectral analysis, is limited by the lack of diagnostic methods for sport practice and availability at an acceptable price. METHOD: Changes of autonomic nervous system (ANS) behavior was evaluated with the help of so-called "short-term" spectral analysis of HRV. This method supplies information on changing ANS activities (sympathetic and vagal subsystems) during the course of physical and psychological load. ANS evaluation was used by means of the telemetric computer-aided system (VariaCardio TF 4) to enable researchers to register the ECG signal, to evaluate the length of RR intervals accurate to 1 ms and to transfer the data with help of a miniature UHF transmitter, even during movement activities. A UHF receiver was connected to a standard serial COM ports of a microcomputer. The system involved software to calculate HRV parameters in time and frequency domains. RESULTS: Evaluation of ANS in the frequency domain is based on "short-term" spectral analysis of HRV (SAHRV) which enables evaluation of ANS effects on the heart rate in 1 to 15 defined load situations, each monitored for 300 seconds. The software procedure directs the course of examination, filtered artifacts and calculated SAHRV parameters according to a partially modified algorithm (CGSAcoarse- graining spectral analysis) (YAMAMOTO et al., 1991) assuring optimum suppression of the noise component of the analyzed signal. The results of SAHRV were POWER SPECTRAL DENSITY( SPECTRAL POWER in the frequency bands of 0.01-0.05 Hz (VLF), 0.05-0.15 Hz (LF), and 0.15-0.5 Hz (HF)( RELATIVE POWER( RATIO POWER( and others . CONCLUSIONS: Experiences with the application of the VariaCardio TF 4 system confirms that examination is not time consuming and the system is easy to use. The corrections in the regulation of the training process, resulting from the obtained data of the ANS examinations, can optimize the whole process and make it effective. REFERENCE: Yamamoto, Y., Hughson, R. L. (1991). Coarse-Graining Spectral Analysis: Next Method for Studying Heart Rate Variability. Journal of Applied Physiology, 71,1143-1150

ON THE OBJECTIVITY OF THE KIHEMATIC DATA OBTAINED FROM KINEMATIC ANALYSES OF THE MOVEMENT

The speed of the transmission of the research results into practice is one of the most important factors for the utilization of the research in sport. New generation of the kinematic analyses based on videotaping of the movement has brought the shortening of the time for elaboration of the taped material. The other possibility how to reduce the time of elaboration of the taped material is to involve more participants in the analysis. The presented paper is focused on the problem of objectivity of the kinematic data analyzed by different people. A special package of software for The Kinematic Analyses of Ski-jumping developed in our laboratory was used. The material taped at the top events - World Championship and World Cups in ski-jumping was used. The sets of university students (n = 10 to 30) have analyzed the taped phases of jumps. The results of the analyses were discussed with regards to various factors such as the quality of the instruction of people engaged in analysing, the experience with this method, the number of checked measurements and the control the final results. In the closing phase the elaboration of the material was realized by two persons who had been working with the system for the whole time of experiment. The results attained by one person during repeated analyses were used as the criterion of objectivity. The statistical analyses of measured values were the basis for derivation of the conditions which are necessary to respect to be able to use the results obtained by different persons for the research