School-Based Circuit Training Intervention Improves Local Muscular Endurance in Primary School Students: A Randomized Controlled Trial.

BACKGROUND: This study aimed to explore the effectiveness of a 12-week circuit training program in improving local muscular endurance in normal-weighted primary school students. METHODS: The study involved a parallel-group randomized trial with 606 primary school boys assigned to an experimental or a control group. The participants underwent a 12-week circuit training program that involved multi-joint, total-body workouts using body weight, resistance bands, and medicine ball exercises. The study measured the participants' local muscular endurance during sit-ups, dynamic trunk extensions on a Roman bench (DTE), and push-ups. RESULTS: After adjusting for the baseline, the treatment-grade interaction was significant for sit-ups (F = 7.74, p < 0.001, ηp2 = 0.04), DTE (F = 6.49, p < 0.001, ηp2 = 0.03), and push-ups (F = 9.22, p < 0.001, ηp2 = 0.05), where the experimental treatment was more beneficial than the control. The treatment effect seemed to vary depending on the individual's baseline local muscle endurance capacity. As the baseline local muscular endurance values increased, the treatment and grade effects became less beneficial. CONCLUSION: A 12-week circuit training program involving body weight, resistance bands, and medicine ball exercises suits school-based programs and can improve local muscular endurance in normal-weighted primary school boys. The experimental treatment was more effective than the control, and the individual baseline muscular endurance should be considered when designing training programs.

The relationship between anthropometric variables and swimming efficiency in early pubescent female front crawl swimmers / Relación entre las variables antropométricas y la eficiencia de natación en nadadoras de estilo crol en la pubertad temprana

SUMMARY: The aim of this study was twofold. The first aim was to examine the association of anthropometric measures on kinematic characteristic which represent stroke efficiency in young female front crawl swimmers. The second aim was to create a prediction model which could provide help to swimming coaches with the purpose of easier and better selection of female front crawl swimmers by measuring and following basic morphological characteristics. Eighty female competitive swimmers all members of the swimming Clubs in province of Vojvodina, Serbia (age 12.52 ± 08 years, years of training involvement 4.05 ± 1.2 and personal best times over 50 m front crawl 32.79 ± 0.86 s) performed 50 m front crawl race. The 50 m front crawl swimming efficiency expressed through stroke index significantly was related to body height (r = 0.44, p = 0.000), body mass (r = 0.402, p = 0.000), sitting height (r = 0.612, p = 0.000) arm spam (r = 0.576, p = 0.000), biacromial diameter (r = 0.470, p = 0.000), bicrestal diameter (r = 0.348, p = 0.001) and with chest circumference (r = 0.427, p = 0.000). Regression equation for stroke index prediction was defined by following variables: body mass, sitting height, arm span, chest circumference with 43.5% explained variance. Additionally by analyzing obtained model the higher the values of SH, ARSP, CHICR and the lower values of BM in a group of early pubescent female swimmers the higher 50 m front crawl efficiency values will be.

Este estudio tiene dos objetivos principales. El primer objetivo fue examinar la asociación de las medidas antropométricas con las características cinemáticas que representan la eficiencia de la brazada en nadadoras jóvenes estilo crol. El segundo objetivo era crear un modelo de predicción que pudiera ayudar a los entrenadores de natación con el propósito de seleccionar mejor y más fácilmente a las nadadoras crol midiendo y siguiendo las características morfológicas básicas. Ochenta nadadoras competitivas, todas miembros de los clubes de natación en la provincia de Vojvodina, Serbia (edad 12,52 ± 8 años, años de participación en el entrenamiento 4,05 ± 1,2 y mejores tiempos personales en 50 m estilo crol 32,79 ± 0,86 s) realizaron una carrera de 50 m estilo crol. La eficiencia de nado crol de 50 m expresada a través del índice de brazada se relacionó significativamente con la altura del cuerpo (r = 0,44, p = 0,000), la masa corporal (r = 0,402, p = 0,000), la altura sentado (r = 0,612, p = 0,000) y el brazo. spam (r = 0,576, p = 0,000), diámetro biacromial (r = 0,470, p = 0,000), diámetro bicrestal (r = 0,348, p = 0,001) y con perímetro torácico (r = 0,427, p = 0,000). La ecuación de regresión para la predicción del índice de brazada se definió mediante las siguientes variables: masa corporal, altura sentada, extensión de los miembros superiores, circunferencia del pecho con una varianza explicada del 43,5 %. Además, al analizar el modelo obtenido, cuanto más altos sean los valores de SH, ARSP, CHICR y los valores más bajos de BM en un grupo de nadadoras púberes tempranas, mayores serán los valores de eficiencia de crol de 50 m.

Trends in Morphological Characteristics among 7- and 11-Year-Old Serbian Children: A Comparison between 1990 and 2020.

Since knowledge possession about the morphological characteristics trend is important to understand, it is necessary to monitor the physical growth and children's development. We have aimed to examine the current state, dynamics, and direction of changes in morphological characteristics, over a 30-year period in Serbian children and adolescents. Morphological characteristics measured in 2020 (n = 304; age 7 ± 6 and 11 ± 6) were compared with the results of same-age children and adolescents from 1990 (n = 1789). The following characteristics were measured: body height, body mass, body mass index, forearm circumference, and upper arm skinfold. The average height (95% IP) of 7-year-old boys was significantly lower in all morphological variables in 1990, compared to their 2020 peers, while in forearm circumference was opposite. As for the 11-year-old boys, body mass (p = 0.02) and BMI (p = 0.009) had significantly better average values in 2020 than 1990, whereas forearm circumference (1.6-2.5 cm) and upper arm skinfold (2.7-4.9 cm) results were opposite. Seven-year-old girls from a 1990 sample also had significantly lower average values for morphological characteristics, compared to their 2020 peers. All morphological characteristic variables of 11-year-old girls have significantly better average values in 1990 sample than in 2020, except for body mass (p = 0.47) and BMI (p = 0.55). The current results have presented a true "picture" of the trends in morphological characteristics status among 7- and 11-year-old Serbian children by comparing them with the already obtained results 30 years ago.

The effects of kinesiology treatment on morphological characteristics of top table tennis players with disabilities / Efectos del tratamiento de kinesiología en las características morfológicas de los mejores jugadores de tenis de mesa con discapacidades

SUMMARY: Sports results of table tennis players with disabilities depend on the functionality level, but also on morphological characteristics. There is an increased risk of obesity in these athletes with disability due to a reduced level of locomotor functionality. The hitherto practice showed that leading table tennis players with disabilities in Serbia did not have an additional kinesiology treatment implemented as part of their training process, which would encourage both strengthening and flexibility of muscle groups relevant for the efficacy of table tennis game, and reduction of body mass and voluminosity. The goal of this paper is to apply an additional kinesiology treatment and determine its effect of on the morphological characteristics of leading table tennis players with disabilities. Eight representatives, table tennis players with disabilities, both male and female, aged between 23 and 52, were included in the additional kinesiology treatment that lasted for nine months. The measures of longitudinal skeleton dimensionality, body mass and volume, subcutaneous adipose tissue and body mass index were analyzed. In order to establish the effects of kinesiology treatment Student's t-test was used, while the results were processed by means of a statistical package SPSS, version 14.0. The values were estimated at p < 0.05 significance level. Male respondents demonstrated statistically significant changes in biceps skinfold (p = 0.05). In the case of female respondents no statistically significant difference was observed in anthropometric space. The additional kinesiology treatment indicates a trend towards reduced voluminosity and body mass of both male and female respondents, but not at a statistically significant level, which is probably the result of an insufficient number of respondents. Continued additional kinesiology treatment should be included in the training process of male and female table tennis players with disabilities, which has not been the case up until now.

RESUMEN: Los resultados deportivos de los jugadores de tenis de mesa con discapacidad dependen del nivel de funcionalidad, pero también de las características morfológicas. Existe un mayor riesgo de obesidad en estos atletas con discapacidad debido a un nivel reducido de funcionalidad locomotora. La práctica hasta ahora mostró que los principales jugadores de tenis de mesa con discapacidades en Serbia no cuentan con un tratamiento de kinesiología adicional, implementado como parte de su proceso de entrenamiento, que fomentaría tanto el fortalecimiento como la flexibilidad de los grupos musculares relevantes para el juego de tenis de mesa, y la reducción de masa corporal y voluminosidad. El objetivo de este trabajo fue aplicar un tratamiento kinesiológico adicional y determinar su efecto sobre las características morfológicas de los principales jugadores de tenis de mesa con discapacidad. Ocho representantes, jugadores de tenis de mesa con discapacidad, tanto hombres como mujeres, con edades entre 23 y 52 años, fueron incluidos en el tratamiento adicional de kinesiología que tuvo una duración de nueve meses. Se analizaron las medidas de dimensionalidad esquelética longitudinal, masa y volumen cor- poral, tejido adiposo subcutáneo e índice de masa corporal. Para establecer los efectos del tratamiento kinesiológico se utilizó la prueba t de Student, mientras que los resultados se procesaron mediante el paquete estadístico SPSS, versión 14.0. Los valores se estimaron a un nivel de significación p < 0,05. Los hombres encuestados demostraron cambios estadísticamente significativos en el pliegue cutáneo del bíceps (p = 0,05). En el caso de las mujeres encuestadas no se observó diferencia estadísticamente significativa en el espacio antropométrico. El tratamiento de kinesiología adicional indica una tendencia hacia la reducción de la voluminosidad y la masa corporal de los encuestados masculinos y femeninos, pero no a un nivel estadísticamente significativo, lo que probablemente sea el resultado de un menor número de encuestados. El tratamiento kinesiológico continuo debe incluirse en el proceso de formación de los jugadores de tenis de mesa con discapacidad, lo que no ha sido el caso hasta el momento.

Physical Activity of Serbian Children in Daycare.

BACKGROUND: Monitoring of physical activity within the educational institution is of great importance, primarily because of the orientation and content implemented in the daycare. This research aimed to examine the number of steps children took during their stay in daycare with regards to age, gender and the frequency of going out. METHODS: The research was conducted in four daycares in the urban environment of Novi Sad (Republic of Serbia), where 231 children, aged 5 to 7, were monitored (129 boys and 102 girls). Data on the number of steps were obtained using the pedometers. RESULTS: The result of the univariate analysis of the variance test confirmed a statistically significant difference in the number of steps in relation to the age of children (p = 0.04). Boys were more active than girls in both age groups (p = 0.001). Children who were going to the daycare yard three to five times a week took drastically more steps than children who went up to twice a week (p = 0.001). CONCLUSION: The results of the current study show that age, gender, and time spent outdoors are significant determinants of physical activity in preschool age. Therefore, interventions regarding physical activity should be made during early childhood in order to promote health and prevent disease.

Evaluation of Gross Motor Coordination and Physical Fitness in Children: Comparison between Soccer and Multisport Activities.

The early detection and continuous monitoring of children's motor competence levels and physical fitness is very important. The purpose of this study was to determine the differences in motor coordination of children enrolled in soccer and multisport activities. The participants of this study included 147 boys and girls (mean age 7.60 ± 0.85 years). The total sample of subjects was composed of two subgroups: children who were enrolled in organized exercise programs-multisports (n = 77), and children who were engaged in soccer training (n = 70). Motor coordination was evaluated with the Kiphard-Schilling body coordination test (KTK). Physical fitness was assessed with a 20 m shuttle run test, 4 × 10 m shuttle run test, standing long jump, and handgrip strength. The ANCOVA showed significant differences (p < 0.05) with large effect size between groups for tests hopping for height (d = 0.93), total motor quotient (d = 1.31), jumping sideways (d = 1.32), and moving sideways (d = 1.59), after adjusting for age and gender. There were no significant differences between groups in the physical fitness tests. It can be concluded that children enrolled in multisport activities have higher levels of motor coordination than children who are enrolled only in soccer. Therefore, multiple sport training programs should be considered and encouraged by parents, educators, and other training professionals.

The connection between certain morphological parameters and results in goalball players / Conexión entre ciertos parámetros morfológicos y resultados en jugadores de goalball

SUMMARY: Certain studies in sports for people with disabilities, also research the morphological characteristics of athletes. However, when it comes to goalball, sport for the people with visual impairments, the focus of researchers is on the population of children and adolescents and the impact of the aforementioned sport on the morphological characteristics that are observed in the process of growth and development. Amongst the population of adults with visual impairment who take part in Goalball, there are almost no studies that deal with the issue of morphological space, especially those that would point towards defining the morphological profile of elite goalball players. The subject of this research are the morphological characteristics of adult goalball players (athletes), and the aim is to determine whether there is a correlation between certain morphological indicators which indicate the status of the body mass of athletes and competition results achieved between goalball teams. The total sample consisted of 22 adult male goalball players, participants of the regional tournament. Morphological space variables, body height, body weight, waist circumference, hip circumference, body fat percentage and muscle tissue percentage were tested and body mass index value as well as the ratio of waist and hip was calculated. Based on the analyzed results, it is concluded that the body height is important in defining the morphological profile of goalball players. In addition to the body height, the indicators pointing to the nutritional status may be taken into account when defining the morphological profile of goalball players (body fat percentage, muscle tissue percentage but also body mass index). Correlation analysis indicated a correlating relationship of the waist and hips with the ranking achievement of the team, which indicates the importance of the body fat distribution in the defining of the morphological profile of goalball players.

RESUMEN: En ciertos estudios sobre deportes para personas con discapacidad también se investigan las características morfológicas de dichos atletas. Sin embargo, cuando se trata de goalball, el deporte para las personas con discapacidad visual, el foco de los investigadores se centra en la población de niños y adolescentes y el impacto del deporte mencionado sobre las características morfológicas que se observan en el proceso de crecimiento y desarrollo. Entre la población de adultos con discapacidad visual que participan en goalball, existen escasos estudios que aborden el tema del espacio morfológico, especialmente aquellos que apuntaran hacia la definición del perfil morfológico de los jugadores de élite de goalball. El objetivo de esta investigación consistió en determinar las características morfológicas de los jugadores adultos y si existe una correlación entre ciertos indicadores morfológicos del estado de la masa corporal de los atletas y los resultados de competencia entre los equipos de goalball. La muestra total consistió en 22 jugadores adultos de goalball, participantes de un torneo regional. Se analizaron las variables espaciales morfológicas, altura, peso corporal, circunferencia de cintura, circunferencia de cadera, porcentaje de grasa corporal y porcentaje de tejido muscular y se calculó el índice de masa corporal así como la relación cintura/cadera. En base a los resultados analizados, concluimos que la altura es importante para definir el perfil morfológico de los jugadores de goalball. Además de la altura, se debe tener en cuenta los indicadores que apuntan al estado nutricional, al definir el perfil morfológico de los jugadores de goalball (porcentaje de grasa corporal, porcentaje de tejido muscular, pero también el índice de masa corporal). El análisis de correlación indicó una correlación entre la cintura y cadera con la clasificación de los equipos, lo que indica la importancia de la distribución de grasa corporal en la definición del perfil morfológico de los jugadores de goalball.

Fully reflective external-cavity setup for quantum-cascade lasers as a local oscillator in mid-infrared wavelength heterodyne spectroscopy.

To our knowledge we present the first experiments with a fully reflective external-cavity quantum-cascade laser system at mid-infrared wavelengths for use as a local oscillator in a heterodyne receiver. The performance of the presented setup was investigated using absorption spectroscopy as well as heterodyne techniques. Tunability over approximately 30 cm(-1) at 1130 cm(-1) was demonstrated using a grating spectrometer. A continuous tuning range of 0.28 cm(-1) was verified by observing the spectra of an internally coupled confocal Fabry-Pérot interferometer and the absorption lines of gas phase SO(2). In a second step the output from the system was used as a local oscillator signal for a heterodyne setup. We show that spectral stability and side mode suppression are excellent and that a compact external-cavity quantum-cascade laser system is well suited to be used as a local oscillator in infrared heterodyne spectrometers.