Reference centiles based on year-to-year changes for a longitudinal evaluation of motor performance in children and adolescents

Objectives The aim was to evaluate the longitudinal course of motor skills development in children with a view to improve the understanding of intra-individual variance. Previous publications have been based on cross-sectional data or analyzed longitudinal studies in a cross-sectional manner. Design Longitudinal. Year-to-year change. Methods The present study is based on motor function data collected in the LIFE Child study (Germany). The participants (6 to 17 years) completed parts of the motor tests according to the standard of the German Motor Performance Test 6–18 (DMT). For a total of 1653 participants, 4616 motor tests with an annual interval in the period 2011 to 2019 were included in the evaluation. Results We were able to produce gender and age-specific change centiles for the test items standing long jump, jumping sideways, push-ups, stand and reach and balancing walking backwards. Each set of centiles revealed a range of variability in motor development in children and adolescents, with distinct progressive patterns in the different test items and different genders. The supplied tables offer an indication of expected year-to-year change for each test item depending on age and gender. Depending on the test item and the mean age, a deterioration in test results after a one-year interval was observed, despite cross-sectional centiles showing an upward trend. Conclusion We present a user-friendly tool as a way to assess individual dynamic changes in motor development of children and adolescents. In combination with the well-known cross-sectional centiles as baseline, this can be helpful for the scientific evaluation of motor skills tests and can also be used in school settings.

Dyslexia and Cerebral Dysfunction

Children with slow visual-motor responses to visual-temporal response tests also have brain dysfunctions in the mobile and motor areas (6, 4). If the left parietal cortex does not participate in these dysfunctions, then this child will also have difficulties in reading. Furthermore, we could say that the brain dysfunctions that are detected by visual-motor tests and that the performance in them is low, are accompanied by difficulties in reading. Aim: In this study we want to show the function of the child's brain in dyslexia. Method: We followed the most up-to-date literature on the subject: neuropsychology and dyslexia. Conclusions: brain organization and its relationship to dyslexia is a major problem for Neuropsychology and Neurolinguistics.

Dyslexia and Cerebral Dysfunction

Children with slow visual-motor responses to visual-temporal response tests also have brain dysfunctions in the mobile and motor areas [6,4]. If the left parietal cortex does not participate in these dysfunctions, then this child will also have difficulties in reading. Furthermore, we could say that the brain dysfunctions that are detected by visual-motor tests and that the performance in them is low, are accompanied by difficulties in reading. Aim: In this study we want to show the function of the child’s brain in dyslexia. Method: We followed the most up-to-date literature on the subject: neuropsychology and dyslexia. Conclusions: brain organization and its relationship to dyslexia is a major problem for Neuropsychology and Neurolinguistics.

Anticonvulsive Effects and Pharmacokinetic Profile of Cannabidiol (CBD) in the Pentylenetetrazol (PTZ) or N-Methyl-D-Aspartate (NMDA) Models of Seizures in Infantile Rats

In spite of use of cannabidiol (CBD), a non-psychoactive cannabinoid, in pediatric patients with epilepsy, preclinical studies on its effects in immature animals are very limited. In the present study we investigated anti-seizure activity of CBD (10 and 60 mg/kg administered intraperitoneally) in two models of chemically induced seizures in infantile (12-days old) rats. Seizures were induced either with pentylenetetrazol (PTZ) or N-methyl-D-aspartate (NMDA). In parallel, brain and plasma levels of CBD and possible motor adverse effects were assessed in the righting reflex and the bar holding tests. CBD was ineffective against NMDA-induced seizures, but in a dose 60 mg/kg abolished the tonic phase of PTZ-induced generalized seizures. Plasma and brain levels of CBD were determined up to 24 h after administration. Peak CBD levels in the brain (996 ± 128 and 5689 ± 150 ng/g after the 10- and 60-mg/kg doses, respectively) were reached 1–2 h after administration and were still detectable 24 h later (120 ± 12 and 904 ± 63 ng/g, respectively). None of the doses negatively affected motor performance within 1 hour after administration, but CBD in both doses blocked improvement in the bar holding test with repeated exposure to this task. Taken together, anti-seizure activity of CBD in infantile animals is dose and model dependent, and at therapeutic doses CBD does not cause motor impairment. The potential risk of CBD for motor learning seen in repeated motor tests has to be further examined.

THE LEVEL OF MOTOR SKILLS DEVELOPMENT COMPARED TO THE REQUIREMENTS OF THE NATIONAL EVALUATION SYSTEM IN GRADE 4 STUDENTS

A good knowledge of the level of development of motor skills of students allows us to identify/improve/establish the level ofmanifestation of its components and the relationships between them. Physical fitness is a strong indicator of health in childhood and adolescence and a main objective for the specialist in the field. In this context, the present study was carried out in 2018-2019and aimed to determine the level of development of motor skills in fourth-grade students from several school units in Craiova, compared tothe requirements of the national evaluation system. Materials and methods.In order to ascertain the level of somatic and motor development of the group included in the present approach, anthropometric measurements and motor testswere applied, namely: height, weight, torso/chest height, abdominal perimeter, arm span,thestanding long jump, supine trunk lifts, the 25mrunning speedand the long-distancerunning. The recording methods applied were those already standardized. Results. Following the analysis of the recorded data we can state that,as far as somatic indicators are concerned, the investigated group presents values below the average of students of the same age in both girls and boys, and there are no significant differences between sexes. However, there is a downward trend inthe average values in the motor tests, many of the recorded values being above therequirements of the national evaluation system. Also, the body mass index calculated for the target group has values that place the studentsin a comfortable range, the average being below the underweight threshold. Conclusions. We consider such approaches very useful, both for a diagnosis of what is actually happening in the school, and forapplying targeted intervention programs to improve any deficiencies.

Physical fitness of candidates to the General Tadeusz Kościuszko Military University of Land Forces

The study is to compare the level of comprehensive physical fitness of accepted candidates to the Wrocław military university in 2015 and in 2019 depending on the type of high school completed. The research material was collected from the motor tests conducted during the recruitment process to the Wrocław military university. The study included measurements of endurance, relative strength, running speed and agility, and swimming skills. The level of all analyzed functional traits of candidates admitted to the university in 2015 is statistically significantly higher compared to men accepted to the university in 2019. The type of secondary school completed does not significantly differentiate the level of comprehensive physical fitness of candidates to the Wrocław military university, both in 2015 and 2019. The type of secondary school completed does not significantly differentiate the level of all-round physical fitness of applicants to the Wrocław military university, either in 2015 or 2019.

Effect of maturity timing on the physical performance of male Polish basketball players aged 13 to 15 years

The aims of this study were (i) to identify the motor potential and basic anthropometric characteristics of Polish basketball players aged 13 to 15 years, (ii) to demonstrate the effect of maturity timing on the results achieved in motor tests and basic body composition parameters, and (iii) to determine which index contributes most to the prediction of performance in the individual tests of speed, jumping ability, agility, and endurance. The sample included 818 male Polish players. Analysis of values related to age-adjusted characteristics showed that in the under 13-year-old group, early maturers had significantly better results (except for stage 1 in the agility test) than average maturers. However, in the endurance test in the under 14- and 15-year-old groups (both distance covered and VO2max), the average maturers obtained higher values. Furthermore, maturity differentiation in the under 14- and 15-year-old groups significantly affected body size, 20-m sprinting time (under 14-year-old group only), and the results of all jumping tests. ANCOVA results (age, body height, and body mass as covariates) showed better results of early maturers in the under 13-year-old group. The opposite trend was observed in the under 14- to 15-year-old groups, where early maturing individuals performed worse in the running vertical jump (VJ) and endurance tests (both distances covered and VO2max). Maturity timing (VJ and VO2max), chronological age (5 m, 10 m, 20 m, agility, and VO2max tests), body height (all tests), body mass (5 m), and the interaction between body mass and height (10 m, 20 m, agility, standing vertical jump, vertical jump) were significant (adjusted R2 = 0.08–0.25; p < 0.001) predictors of motor skills. These findings can be helpful in quantifying and controlling the results of youth sports programs adjusted to biological requirements used in the training process.

Analysis Of The Effect Of Frequency Decrease On Performance On Five Phase Induction Motor

Almost 70% of the energy produced by the generator is consumed by electric motors. The use of induction motors in industry and factories is more profitable than DC or synchronous motors, one of the advantages is easy maintenance and high efficiency. On machines in the industry speed regulation is absolutely necessary. Along with the development of power electronics, this has become very easy to do, namely by supplying a motor with a variable speed drive (VSD) inverter. With the supply of a variable speed drive inverter, it is possible to adjust the motor speed by adjusting the voltage frequency.This study was conducted to determine the effect of decreasing the frequency using a variable speed drive inverter on the performance of a five-phase induction motor. Tests are carried out at a frequency of 50 Hz (grid frequency), 35, 40, 45, 50 Hz (inverter frequency) and the motor is loaded at 0.5, 1, 1.5, 2, 2.5Nm. From the research, it was concluded that, among others, the use of a variable speed drive inverter resulted in greater motor losses and the motor produced a louder sound. At the same frequency (50 Hz) the efficiency of the motor is better when supplied directly from the grid.

Ways of improving the method of control of coordination preparation of young athletes in playing sports

Today, there is a further increase in the demands for the effectiveness of competitive activities of athletes in playing sports. This, in turn, requires improving the individual skills of players. The factor of «technical-coordination» is one and the most important for achieving high sports results in sports games. Analysis of the scientific literature shows that there are no uniform standardized criteria for assessing the coordination abilities of young athletes. In the training process of representatives of play sports, mainly comprehensive tests are used to evaluate coordination preparedness, in which it is very difficult to assess the degree to which some form of coordination capability has been developed. When designing a test program to assess the coordination skills of players, it is necessary to rely on tests that assess the types of coordination abilities that are most relevant to a particular sport specialization. Given the difficulty of using instrumentation methods to study the coordination of movements in the daily training activities of players, motor tests continue to be the main way to assess the coordination abilities of young athletes in playing sports. This requires further improvement in their informativeness and reliability.