CHANGE OF ECG PARAMETERS DEPENDING ON THE LOAD LEVEL IN ATHLETES

The influence of physical training on bodies of athletes leads to changes that can be characterized as morphological, functional, electrophysiological and psychological. Dynamic exercise, such as running, swimming and riding a bicycle, leads to volume load of heart. Static exercise (gymnastics, weightlifting, wrestling) leads to the development of relatively large muscle force, with or without changes in muscle length and movement of the joint. Given the frequent number of sudden cardiac death cases in sport, it is important to distinguish between changes of the heart that occur as a result of adaptation to physical activity and changes due to some pathological conditions. The aim of this paper is to present the latest information on changes in ECG parameters depending on the load of athletes while performing aerobic trainings in order to better identify markers of adverse cardiovascular events, particularly sudden death in athletes. It is common to see on the ECG of athletes at rest hypertrophy of the left and right ventricle, interventricular conduction disorder, positive ST changes, and short-term tachycardia. Changes that occur in athletes are due to increased vagal tone and suppression of sympathetic nerve regulation. Many changes can be attributed to intrinsic cardiac component that is responsible for the lower frequency of athlete's heart deinnervation (with atropine or propranolol), which means that intense training influences how the autonomic regulation and the intrisic cardiac pacemaker function. It is common for athletes to have sinus bradycardia, sinus arrhythmia, first degree AV block and Mobitz I, as well as junctional rhythm, ST segment elevation, high and sharp, or biphasic T-waves, while ST depression or isolated T-wave inversion are less common. They can also have increased amplitude of P-wave and QRS complex, QRS axis rotation to the right and incomplete right branch block. Some but insufficient data tell about the presence of the third-degree AV block and atrial and ventricular ectopic beats and their predictive role for malignant rhythm disorders

THE EFFECTS OF THE ARTHISTIC GYMNASTICS PROGRAM ON PHYSICAL FITNESS OF ADOLESCENTS

The aim of the research is to determine the effects of the arthistic gymnastics program on the Physical fitness of adolescents. The sample of participants consisted of 28 participants, males, aged 14 years ± 6 months, seventh grade of "Bubanjski Heroji" elementary school in Niš. The sample was divided into two subgroups. The experimental group (EG) consisted of 14 participants who, during the experimental period, realized the program of artistic gymnastics during the main phase of a physical education class, ten weeks in two classes of 45 minutes. The control group (CG) consisted of 14 participants who during the experimental period realized the program contents of regular physical education in the main phase of physical education. The sample of motorized measuring instruments consisted of three variables of explosive power (standing long jump, triple jump off the site and vertical jump) and three variants of sprint run (20m flat out with a flying start flat out with a flying start, 30m flat out with a flying start flat out with a flying start and 50m flat out with a flying start flat out with a flying start). The program "Statistica" 8.0 for Windows was used, for calculation of basic statistics, canonical discriminatory analysis and multivariate analysis of covariates. The results of the study showed that there are statistically significant effects of the use of the artistic gymnastics exercises in the main part of the physical education course on the Physical fitness of the adolescent of the EG at the end of the experimental period

EFEKTI PROGRAMA AKROBATIKE NA TELESNU KOMPOZICIJU I FLEKSIBILNOST ADOLESCENATA

The aim of the research was to determine the effects of acrobatics programs (ground floor and skipping) on the body composition and flexibility of adolescents. The sample consisted of 50 male adolescents, seventh grade students of the elementary school "Bubanjski Heroji" in Niš, aged 14 years ± 6 months. The experimental group (n = 25) conducted 2 x 45 min per week experimental acrobatics program (ground floor and skipping) The control group (n = 25) continued with the program of regular physical education classes (handball and volleyball) 2 x 45 min per week. The results of the study showed positive changes in body composition: BMI, %MAT, %MIT and flexibility: PLNL, RANL, ISKP caused by the acrobatics program. Based on these results, it can be concluded that the experimental program of acrobatics lasting 16 weeks is an effective method that leads to a statistically significant improvement in body composition and flexibility of adolescents.Cilj istraživanja bio je da se utvrde efekti programa akrobatike (parter i preskok) na telesnu kompoziciju i fleksibilnost adolescenata. Uzorak ispitanika činilo je 50 adolescenata muškog pola, učenika sedmog razreda osnovne škole ”Bubanjski heroji” u Nišu, starosti 14 godina ± 6 meseci. Eksperimentalna grupa (n = 25) je sprovodila 2 x 45 min nedeljno eksperimentalni program akrobatike (parter i preskok) Kontrolna grupa (n = 25) je nastavila sa programom redovne nastave fizičkog vaspitanja (rukomet i odbojka) 2 x 45min nedeljno. Rezultati studije pokazali su pozitivne promene u telesnoj kompoziciji: ITM, %MAT, %MIT i fleksibilnosti: PLNL, RANL, ISKP izazvane programom akrobatike. Na osnovu ovakvih rezultata može se zaključiti da je eksperimentalni program akrobatike u trajanju od 16 nedelja efektivan metod koji dovodi do statistički značajnog poboljšanja telesne kompozicije i fleksibilnosti adolescenata

CHANGES IN LIPID PARAMETERS AND ANTROPOMETRIC INDICATORS OF DIETING DURING THE PERIOD OF INTENSIVE PREPARATIONS OF TOP ATHLETES

Physical exercise is a planned and repeated exercise aiming to maintain and improve one or more aspects of physical condition. Increased sympathetic-adrenal activity and reduction of insulin concentration are the main stimuli of lipolysis during physical activity.The aim of this study was to investigate acute and chronic effects of intensive aerobic training program on lipid profile and antropometric parameters in young healthy soccer players.Fifteen healthy male (soccer players, average age 21.4±3.6) were included in this study. Soccer players had a minimum of 6 months continuous training that consisted of three training sessions per week. They did not smoke, take drugs or drink alcohol during the examination period. A balanced diet (60% carbohydrates, 25% lipids and 15% proteins) was recommended by a nutritionist as a standard diet during the preparations period. This consisted of three repetitions of 20-min running sessions, with two 3-min breaks in-between. Target load was obtained at 120–140 bpm heart rate. Anthropometric estimation comprized determination of body fat % by impendansometer Omron BF306, body height (BH), body weight (BW), waist circumference (WC), waist/hip ratio (WHR) and determination of body mass index (BMI=BW/BH2). Blood samples were taken prior to and 5-10 min after completion of exercise. Biochemical investigation comprized spectrophotometric determination of total cholesterol (TC), triglicerides (TG), HDL-C and low-density lipoprotein cholesterol (LDL-C). There was a significant reduction of body fat content % after 6 months of intensive physical preparation (p<0.05), but not of BMI and BW. There were no signifficant changes in waist circumference and WHR values at the end of physical preparation compared to the values from the beginning. There were not significant changes in TC and TG levels at the end of 6 months preparations; however significant changes in lipid fractions were present. There was a significant decrease in LDL-C levels and an obvious increase of HDL-C at the end of the preparations. The acute changes in lipid parameters comprised significant increase of TC and HDL-C, while there were no significant changes in LDL-C and TG levels.The results of this study demonstrate that a well balanced physical training of soccer players leads to significant changes in lipid profile but no changes in body mass. This type of training also decreases percentage of total body fat