Influence of body build on hand grip strength, simple reaction time and strength of the abdominal muscles in prepubertal children.

The aim of the study was to assess whether the body build has an impact on hand grip strength, muscle endurance and time reaction in children. The material of the research were 376 children from 6.78 to 11.82 years old in 2018. Body weight, height, waist, hip and mid-upper-arm circumferences, triceps and subscapular folds were measured. The BMI, body fat and AHtR (arm-circumference-to-height ratio) were calculated. The hand grip strength, simple reaction time (Quickstick) and strength of the abdominal muscles (endurance) were tested. Two-way ANOVA and correlation analyses with significance level p < 0.05 were used. Children with normal BMI values are characterized by better simple reaction time than their obese peers, while overweight and obese children estimated on the basis of BMI, AHtR and body fat perform were better in hand grip strength. In the case of strength of the abdominal muscles, there were no differences in children with different body build. The normal build and body weight promotes the proper development of children, which also is reflected in the results of motor performance and fitness tests.

Body structure, muscular strength and living conditions of primary school children in Warsaw.

The aim of this study was to determine whether the living conditions of school children affects their body structure and muscular strength. Data were taken from 400 girls and 341 boys aged 7-15 years attending nine primary schools in Warsaw in 1997. A questionnaire was completed, anthropological measurements made and two muscular strength tests conducted. The questionnaire asked questions on the children's level of education, their parents' professions and monthly incomes, the number of persons in the family and the number of rooms in the family's apartment/home. Body height, body weight, chest and arm circumferences, grip strength and vertical jump height were measured and used to calculate body mass index, Marty's Index and the Sargent Vertical Jump Index. Statistical tests included Student's t-test, Principal Component Analysis (PCA) and multiple regression analysis. Body height, chest circumference, Sargent Vertical Jump Index and grip strength were significantly greater in the boys than the girls. Two factors, namely 'socioeconomic status' (F1) and 'family size' (F2), describing living conditions, were isolated after PCA. Boys from bigger families (F2) were shorter, with lower weights and BMIs, smaller chest and arm circumferences and greater grip strengths than those from smaller families, whereas girls from families of lower socioeconomic status (F1) weighed less and had greater BMIs and arm circumferences than those from higher socioeconomic status families. The results suggest that boys seem to be more 'ecosensitive' than girls.

Socio-economic determinants of the somatic development and reaction time of vegetarian and non-vegetarian children.

Introduction: Vegetarian diet is increasingly used in both adults and children. Study aim: The aim of the study was to determine the differences in the body build and reaction time of vegetarian and non-vegetarian children on the background of socio-economic factors. Material and methods: The material consisted of 218 children, including 47 vegetarians (25 boys and 22 girls) and 171 non-vegetarians (93 boys and 78 girls) from 3 to 15 years. The research consisted of a survey and measurements. The survey included questions such as date of birth, child's birth parameters (length, weight, Apgar scores), child's diet (vegetarian/non-vegetarian), mother's diet during pregnancy (vegetarian/non-vegetarian), breastfeeding (yes/no), number of months of breastfeeding, mother's diet during lactation (vegetarian/non-vegetarian), maternal and parental education level (elementary / trade/ college / university), living conditions and the number of siblings. The height and body mass, skin-fat folds on the abdomen, shoulder and arm (sum of 3 skinfolds) were measured, BMI was calculated and the reaction time was assessed using the Quickstick ruler. The General Linear Model, Wald's test, U-Mann-Whitney test and Principal Components Analysis were applied. Results: The results showed that vegetarian children who came from families with a higher socio-economic status than non-vegetarian were significantly longer breastfed. The somatic build of vegetarian children, including height, BMI and the sum of three skinfolds significantly differed from non-vegetarian children. The vegetarian children were shorter, with lower BMI and lower sum of the three skinfolds, as well as their reaction time was longer. Conclusions: Vegetarian diet affects the height, BMI and body fatness, as well as the reaction time in children at the age of 3-15.

Age at maturation, body structure and their relationship with socioeconomic factors.

Introduction: In this study, we aimed to identify the differences in body structure between early, average, and late maturing girls, taking into account family characteristics assessing socio-economic and living conditions. Methods: This study was conducted in the years 2003 and 2013 in Warsaw, Poland and comprised 788 girls in the age group of 11-19 years. The data were collected using a questionnaire which included parental education and profession, girls' date of birth, age at menarche, and lifestyle characteristics. The measurements included height; weight; skinfolds on arm, under scapula, and on abdomen; arm circumference; and body mass index (BMI). The girls were divided into three groups: early, average, and late maturing. To eliminate the age differences, for each of the examined somatic variable, a "z" score was calculated. We analysed the combined data of both years (2003 and 2013) due to the lack of difference in the mean age at menarche. The primary objective of this study was to assess the relationship between somatic body structure and socioeconomic and lifestyle factors among early, average, and late maturing girls. Results: Early maturing girls possessed higher body weight and BMI. In families with only one child, the age at menarche was found to be the earliest than in families with more than one child. Body weight, BMI, arm circumference, and fatfold thickness was found to be reduced in case of girls whose parents had better education and profession than their peers. Higher levels of stress were associated with higher body mass, greater BMI, arm circumference, and skinfolds in early maturing girls. The associations between body structure with physical activity and family was mainly correlated with body weight and BMI. Conclusion: Socioeconomic and lifestyle factors may be helpful in some levelling of differences in the body structure between girls differing in the age at menarche, especially the level of stress and the education and profession of parents.

Meeting Report: Growth and Social Environment. Proceedings of the 25th Aschauer Soiree, held at Krobielowice, Poland, November 18th 2017.

Twenty-two scientists met at Krobielowice, Poland, to discuss the impact of the social environment, spatial proximity, migration, poverty, but also psychological factors such as body perception and satisfaction, and social stressors such as elite sports, and teenage pregnancies, on child and adolescent growth. The data analysis included linear mixed effects models with different random effects, Monte Carlo analyses, and network simulations. The work stressed the importance of the peer group, but also included historic material, some considerations about body proportions, and growth in chronic liver, and congenital heart disease.

Variation in indicators of respiratory functions among Warsaw adolescents in relation to ambient air pollution and smoking.

This work presents results of studies on secondary school adolescents inhabiting two regions of Warsaw: Sródmiescie district (Downtown) and Miedzylesie (Wawer district - Vicinity), conducted in 2006. These two districts significantly differ according to air pollution, which is much higher in Downtown than in Vicinity. The sample consists of 219 boys and 225 girls aged 13-16 years. The measurements included body height and weight and 8 respiratory variables of lung function: VC, FEV1, TV, MV, IRV, ERV, Ap, RR. Additionally information about education of parents, number of children in family, number of rooms in a house/apartment, smoking habits of pupils and their parents were provided. Sib-sib size, parents education level and number of rooms in apartment or house were included in a principal component analysis (PCA) to obtain a common factor representing general socio-economic status (SES) for families. First factor scores were used as covariates in the further analysis. The influence of air pollution on respiratory variables was evaluated using the analysis of covariance (ANCOVA). The results show that there are significant relations of air pollution to Ap, MV and IRV and smoking habits of individuals on their MV and TV. In the heavier polluted region there are observed longer time of Ap and higher values of IRV There is an opposite reaction of MV on air pollution and smoking. The MV values are lower in the heavier polluted area but presents greater values in smoking individuals. Also values of TV are greater if individuals smoke comparing with non smokers.

Does a seasonal developmental rhythm exist in tropical living populations?

The main aim of this work concerns the answer a question whether the general regularity of seasonal differences in changes of height, weight and body components during ontogeny exist. If so, whether this phenomenon depends on cyclic changes in nature or this rather is an adjustment to local conditions and mode of life. To answer this question the studies took place in the tropical climate of Yucatan and included 49 boys and 47 girls aged 11-12 years and being of the Maya, Mestizo and Creole origin. The youths were attending two schools which were located in rather poor districts of Merida (capital city of the Yucatan State, Mexico). The investigations started in February 2002 and ended in November 2003 and were continued monthly. The standard anthropometric methodology was applied to measure body height, weight, arm, waist, hip and calf circumferences and five subcutaneous fat folds (biceps and triceps brachii, subscapular, suprailiac and calf). Bioimpedance techniques were used to measure fat mass (FM), fat free mass (FFM) and total body water (TBW). The results show that monthly or longer rates of stature increments and increments or declines of body mass do not exist. The similar observations were mentioned according to daily studies of similar type in literature. There are not similar regularities of changes even in groups of coevals of the same gender and within the youths coming from the same district. Each variable shows a quite specific rate of changes.