Sexual dimorphism of adiposity and fat distribution among children and adolescents (8-18 year olds) from Poland.

OBJECTIVES: The study aimed to analyze the sexual dimorphism of total body fat [BF%] and fat distribution among 8-18 year olds from Poland. METHODS: The study included 2175 participants, divided into sex and age groups. Waist and hip circumferences, the thickness of six skinfolds, waist-to-hips ratio [WHR], the ratio of abdominal-to-suprailiac skinfolds, and the limb-to-trunk adiposity index were analyzed. Fat percentage were measured with a body composition analyzer (Tanita) with accuracy 0.1%. The Mollison's Index [MI] was used for calculating sexual dimorphism. RESULTS: The value of MI for the WHR and its components (waist and hip circumferences) was negative (the boys were characterized by higher values of these parameters). The magnitude of the sex differences was lower in the younger age groups and the highest in the oldest groups. For adiposity [BF%], the average values were higher in females. In the younger age groups, girls had thicker skinfolds compared to boys, and this tendency was also observed in the older age groups, except for abdominal and suprailiac skinfolds. The values of the analyzed adiposity indicators also represented a tendency toward central allocation of fat tissue in boys. CONCLUSIONS: In conclusion, sexual dimorphism of fat distribution and adiposity could be detected as early as 7 years of age. These differences can be identified using simple anthropometric methods, which are relatively cheap and easy to use, particularly in the field setting and large populations. The observation of changes in these features in children should be a recommended procedure aimed at early detection of overweight, obesity, as well as normal weight obesity or other metabolic disorders.

Changes in physical fitness and body build of women and men surveyed in 2004 and 2022-A longitudinal study.

Physical fitness plays a crucial role in determining human health and overall well-being. The objective of the study was to assess the changes in body structure and physical fitness among individuals examined in 2004 and 2022 (persons aged 32-34 and 50-52). The research material consists of data from the Krakow Continuous Study (KCS) of somatic development and physical fitness of people born in 1970 and 1972, conducted in Krakow in the years 1976-2022. In total, in 2004, 103 women and 122 men took part in the study, and in 2022-47 women and 67 men. Of these participants, 37 women and 53 men were present for both measurements. The following measurements were performed-physical fitness tests: handgrip strength of left and right hand, standing broad jump, sit-and-reach test and overhead medicine ball throw (2 kg); anthropometric measurements: body height, body weight and tissue composition, circumferences of the chest (relaxed and in deep inspiration), waist, hips, thigh, mid-upper-arm (MUAC, relaxed and in deep inspiration), forearm and calf, thickness of biceps, triceps, subscapular, abdominal, suprailiac and calf skinfolds; width of shoulders and hips, depth and width of the chest. A comparative analysis of the two series showed that all fitness test scores deteriorated. The percentage decrease was greater in women than in men in the tests of right and left handgrip strength and overhead medicine ball throw than in men, in the standing broad jump test similar in both sexes, in the sit-and-reach test-lower in women than in men. The greatest decreases were observed in the standing broad jump (by 14%) and the 2 kg medicine ball throw (15-12%), both in women and men. In contrast, the level of development of most of the somatic characteristics studied in 2022 was higher compared to the previous study, and, apart from body height, elbow and knee width and calf skinfold in both sexes, the differences in arithmetic means between the 2004 and 2022 series were statistically significant. Furthermore, the absence of involutionary changes in body height can be highlighted. In conclusion, the decrease in physical fitness occurring in adulthood and the increase in most somatic characteristics between 32 and 34 year-olds and 50 and 52 year-olds were confirmed.

The Normal Weight Obesity (NWO) Problem-Prevalence and Time Changes in Children and Adolescents From Kraków (Poland).

OBJECTIVES: Normal weight obesity can be associated with an increased risk of metabolic abnormalities, systemic inflammation and mortality. The main aim of the study was to analyze the changes in the prevalence of normal weight obesity in 8-18-year-olds from Kraków (Poland) between 2010 and 2020. METHODS: The study was based on two sets of cross-sectional, school-based data obtained in 2010 and 2020. Body height, weight, and fat percentage were obtained. Body mass index was calculated, and only normal-weight individuals were included. Normal weight obesity was defined as normal BMI with adiposity >85 percentile for age and sex. RESULTS: The prevalence of normal weight obesity among Polish children and adolescents has been alarming for at least the last 10 years. Depending on the sex and age, normal weight obesity was present in more than 10% up to even more than 20% of the examined population. CONCLUSIONS: Alarming numbers of Polish children and adolescents suffer from NWO and this problem seems to be present for at least the last decade. A need for a maximally universal definition and cut-offs to diagnose normal weight obesity should also be stressed, as it will be helpful in providing the best prophylaxis and help to persons already suffering from normal weight obesity.

Association between physical fitness and normal weight obesity in children and adolescents from Poland.

OBJECTIVES: Normal weight obesity (NWO) is defined as elevated adiposity, despite normal body mass index (BMI). The aim of this study was to compare the results of selected fitness parameters in Polish children and adolescents from Poland with and without normal weight obesity. METHODS: The study was cross-sectional and school-based. Body height, weight and adiposity, as well as the results of selected fitness tests, were obtained. BMI was calculated, and only normal-weight individuals were included. NWO was defined as normal BMI with adiposity ≥85 percentile for age and sex. RESULTS: Children with NWO tended to have better results of absolute dynamometric strength and overhead medicine ball throw. On the other hand, when the dynamometric strength was normalized for the body mass nonNWO group achieved better results. Furthermore, NWO group had lower explosive muscle strength of the lower limbs, agility, as well as abdominal muscle strength, and endurance. CONCLUSIONS: Obtained results suggest that NWO is associated with a decrease in at least some fitness parameters in children and adolescents. Therefore, it can be hypothesized, that normal weight obesity can result in poorer fundamental motor skills. Moreover, as parameters such as muscle strength have been shown to be associated with cardiometabolic risks, described results can also be important in the context of the present and future health of the children. The results also highlight the importance of monitoring physical fitness and body composition in children, as individuals with NWO are almost indistinguishable from normal weight non-obese counterparts based on current standard surveillance protocols.

Analysis of secular trends in physical fitness of children and adolescents (8-18 years) from Kraków (Poland) between 2010 and 2020.

OBJECTIVES: The aim of the study was to analyze the changes of the motor skills of children and adolescents from Kraków between 2010 and 2020. METHODS: The group included 4106 children and adolescents (8-18 years of age). The analysis of changes included results of the following fitness tests: backwards overhead medicine ball throw, standing broad jump, dynamometric strength of the hand, flexibility test, as well as shuttle run (10 × 5 m). RESULTS: A negative trend in both sexes was observed in the results of overhead medicine ball throw. The girls also had a negative intergenerational changes in the results of the shuttle run and the flexibility test. A positive secular trend was also observed in both sexes in relations to the dynamometric force of the right and left hand. In addition, the boys studied in more contemporary times showed better results in the shuttle run, compared to their peers in 2010. CONCLUSION: The study reported a decline in overall motor performance in children and adolescents. The observed results may be related to a decrease in the level of physical activity, as well as a higher incidence of overweight and high levels of body fat in the modern population.

Changes in the prevalence of underweight, overweight, obesity and excessive adiposity among adolescents from Kraków (Poland) in the years 1983-2020.

OBJECTIVES: Improved living conditions affect lifestyles and may contribute to the increased prevalence of overweight and obesity among adolescents. The aim of the study was to analyze changes in the prevalence of underweight, overweight, obesity as well as excessive adiposity among teenagers from Kraków (Poland). METHODS: The study was conducted in four series in the years: 1983, 2000, 2010, and 2020. The study group included 1759 boys and 1699 girls aged 16-18 years. body mass index (BMI) was calculated on the basis of body height and weight. Adiposity was measured by bioimpedance method. Participants were grouped according to BMI categories using Cole's cut-off points and according to adiposity based on mean and standard deviations values. The significance of the differences between cohorts was assessed by the Chi-square test. RESULTS: Secular increase in the prevalence of underweight and overweight was observed among girls in most age groups. An increase in the prevalence of high body fat was also observed among 16- and 17-year-old girls - the opposite trend was noted in 18-year-old girls. Contemporary boys had an increased prevalence of overweight and obesity in each age group. CONCLUSION: There was a significant increase in the prevalence of body weight abnormalities in the study population. The observed results may be related to socio-economic changes that adversely affect the lifestyle of the society. The results are also important in terms of the health of future generations and may be helpful in the development of new prevention and intervention programs.

Changes in the adiposity level and prevalence of overweight/obesity among children from Kraków (Poland) within the last decade (from 2010 to 2020).

The aim of this study was to assess the changes in the prevalence of overweight, obesity and high adiposity in children and adolescents from Krakow (Poland), between the years 2010 and 2020. Two cross-sectional series of anthropometric measurements were carried out in 2010 and 2020. Analysed characteristics included: body height and weight, BMI (Body Mass Index), body adiposity (%BF). The subjects were categorised according to their BMI (underweight, normal weight, overweight, obesity), as well as %BF (low, normal, high body fat).The research was conducted in randomly selected primary schools in Krakow (Poland). Studied cohorts (8-15 years of age), which represented four of the traditional residential districts: Sródmiescie, Podgórze, Krowodrza and Nowa Huta. Among the girls, there was a negative secular trend regarding the prevalence of underweight and obesity. On the other hand, there also was a positive trend concerning the prevalence of overweight and low and high body fat. In boys, there was a negative secular trend regarding the prevalence of underweight and low adiposity. There was also a generally positive secular trend regarding the prevalence of overweight, obesity as well as high adiposity in boys. The findings of this study are particularly significant because detailed knowledge of the prevalence of overweight/obesity in childhood and adolescence is crucial for the future health of entire populations. Further studies should also take into account the levels of physical fitness and activity of the examined population.

The impact of neonatal parameters and parental factors on body fat level in early childhood.

Parental and pregnancy characteristics can affect proportions and tissue composition of the child's bodyand thereforecan influence their present and future health, as well as overall wellbeing. The aim of this study was to examine the differences between selected parental and birth-related parameters among preschool (3-7 years of age) children of varying adiposity status (n=541 girls and n=571 boys).The research was carried out in 20 randomly selected kindergartens in Krakow (Poland). Thickness of 6 skinfolds (biceps, triceps, subscapular, suprailiac, abdominal and calf) was measured. Sum of skinfolds was calculated and participants were divided into low, normal or high body fat groups. Birth-related characteristics were obtained using a questionnaire filled out by the children's parents. Children of mothers who gained the most gestational weight were characterised by high adiposity. Preschoolers with the highest birth weight, body length and head circumference had the greatest adiposity. Children of relatively younger mothers had higher body fat, in comparison to the rest of the study group. Parents of preschoolers in the high adiposity category were characterised by a greater body mass, compared to the parents of children in other body fat groups and that boys with the highest adiposity relatively more often had a close relative with obesity. Children in varying adiposity categories differed in terms of some birth-related factors. Particular attention should be paid to familial and parental characteristics, because they may influence the child's predisposition to excess adiposity deposition later in life.

Body composition of children with different gestation time.

OBJECTIVES: To examine the differences in body composition between prepubescent children, depending on the time of gestation. METHODS: The study was conducted among children aged 3-10 years. The thickness of 5 (triceps, subscapular, suprailiac, abdominal, calf) skinfolds, mid-upper arm circumference, body height, weight and femur breadth was measured. Sum of 3 skinfolds, Body Mass Index (BMI) and muscle mass were calculated. Gestation time was obtained using a questionnaire. RESULTS: Children in the short gestation time category were generally characterized by the greatest values of the analyzed characteristics, particularly above the ages of 6-8 years. Femur breadth and muscle mass were similar up to the mentioned age in all of the gestation time categories. BMI and all of the adiposity characteristics, below the age of 6 years, were the greatest in the long gestation time category. CONCLUSIONS: Results of the present study are important, as excess body mass and adiposity are associated with increased risk of cardiovascular and metabolic abnormalities later in life. Special emphasis should be placed on the prevention of overweight and obesity among premature babies and the education of their parents.

Secular changes in the waist, hips circumferences and selected associated indicators, among preschool children from Kraków (Poland), between 1983 and 2018.

OBJECTIVES: Waist circumference and derived indicators are great for measuring the risk of abdominal obesity. The main aim of the study was to assess the changes in the waist, hips circumferences and selected associated indicators, among preschool children (3-7 years of age) from Kraków, Poland, between 1983, 2008 and 2018. METHODS: The research was conducted in randomly selected kindergarten in Krakow (Poland). The 1983 cohort consisted of 1414 children and the 2008 and 2018 series included 1050 preschoolers each. Analyzed characteristics included waist and hip circumferences, body height, waist-to-hips ratio (WHR) and waist-to-height ratio (WHtR). RESULTS: There was a negative secular trend regarding circumferences of the hips and waist, as well as WHtR. In girls, WHR was, the greatest in the 2018 cohort, while among boys there was a secular increase in the value of this parameter compared to the 2008 cohort, but not to the 1983 series. CONCLUSIONS: The coexistence of currently noted trends with the previously described secular decrease in the prevalence of overweight/obesity and increase in trunk adiposity in the same population, suggests that WHR is preferable to body mass index in assessing the risk associated with excess adiposity in the population examined in the presented study.

Associations of anthropometric cardiometabolic risk factors and leg fat accumulation in children and adolescents from Poland.

OBJECTIVES: To analyze the correlation between anthropometric cardiometabolic risk factors with calf adiposity in 4-16-year-olds from Poland. METHODS: Three thousand seventy-six persons (1568 girls and 1508 boys) were examined. Analyzed characteristics included body height, waist, hips and neck circumferences, body weight, six skinfolds. The following were calculated: body mass index (BMI), waist-to-hips ratio (WHR), the sum of all skinfolds, and the sum of skinfolds on the waist area. RESULTS: The relationship between the calf skinfold and the rest of the characteristics was estimated using multiple regression. There was a negative relationship between calf adiposity and fat tissue accumulated around the waist and the BMI (in some groups). This suggests that participants with greater calf adiposity had lower waist adiposity and BMI than those with less fat tissue on the lower limb. CONCLUSION: Persons with higher calf adiposity may have a lower cardiometabolic risk. This observation is significant because cardiovascular risk factors can persist from childhood into adulthood. Additionally, cardiovascular issues have numerous medical consequences but also socio-economic ones, thus they can affect individuals and be a burden on public health.

Body height, weight, and Body Mass Index - magnitude and pace of secular changes in children and adolescents from Kraków (Poland) between 1983 and 2020.

OBJECTIVE: The aim of this study was to analyze the occurrence and pace of secular trends regarding body height, weight, and Body Mass Index (BMI) among children and adolescents from Kraków (Poland) examined in 1983, 2000, 2010, and 2020. METHODS: The study group consisted of 17 407 individuals (8650 girls and 8757 boys) aged 3-18 included in four cross-sectional studies conducted in 1983, 2000, 2010, and 2020.Analyzed anthropometric characteristics included body height (measured according to Martin's technique, with an anthropometer) and body weight. BMI was calculated as follows: body weight (kg)/body height2 (m). RESULTS: Results of the current study suggest that there was a cessation of previously observed secular increase of the body height in the examined population in the recent decade. Additionally, secular changes regarding body height, body mass, and BMI occurred noticeably slower in the recent decade compared to the previous years. CONCLUSIONS: In conclusion, the rapid increase of body height in the years 1983-2000 and later secular increase of the body mass and BMI in 2000-2010 were probably associated mainly with significant socio-economic progress of the country. On the other hand, deceleration of those trends in 2010-2020, especially in regards to body height, may be associated with reaching the maximum genetically attainable body height in the examined population.

Changes in adiposity and fat tissue distribution among preschool children from Kraków, Poland, from 2008 to 2018.

In the light of changes in the living conditions of populations, excess adiposity is currently a serious public health problem worldwide. The aim of this study was to assess the changes in the body fat ratio among preschool children aged 3-7 years from Kraków, Poland, between 2008 and 2018. The study group consisted of children examined in two cross-sectional studies. Analysed characteristics included triceps, calf, subscapular, abdominal and suprailiac skinfold thicknesses, and adiposity calculated according to Slaughter's equations. The trunk adiposity index and limbs-to-trunk fat ratio were also calculated. Statistical significance was obtained using two-way ANOVA and Tukey's tests. Lower-limb adiposity was largest in the 2008 cohort and trunk adiposity was greater in the 2018 cohort. The mean values of the trunk adiposity index and limbs-to-trunk fat ratio were lower in the 2018 cohort than in the 2008 cohort. The 2018 cohort was also characterized by a lower overall adiposity. Regardless of the lower body adiposity percentage, in 2018 there was a tendency towards the central allocation of fat tissue. This is a negative phenomenon because, especially when co-existing with reduced lower-limb adiposity, it is associated with an increased risk of metabolic and cardiovascular diseases, even in young children.

The impact of lifestyle and socioeconomic parameters on body fat level in early childhood.

The aim of this study was to examine the differences between selected lifestyle and socioeconomic parameters among preschool (3-7 years of age) children of differing adiposity status. The study was conducted from February to June 2018 in 20 randomly selected kindergartens in Kraków, Poland. Triceps, biceps, subscapular, suprailiac, abdominal and calf skinfold thicknesses were measured. The sum of all six skinfolds was calculated and the children were subsequently characterized by low (≤-1 SD [standard deviation]), normal (-1 to 1 SD) or high body fat (≥1 SD). Socioeconomic and lifestyle characteristics were obtained using a questionnaire filled out by the children's parents or legal guardians. Preschool children in the high adiposity category had, on average, fewer siblings and longer screen time; additionally, their parents had lower education and more often worked in manual jobs, in comparison to the children in the low and average adiposity categories. In conclusion, it was observed that children in different adiposity categories varied in terms of some socioeconomic as well as lifestyle characteristics. Knowledge regarding the influence that those factors can have on the metabolic health of children is essential for children's present as well as future well-being. Moreover, it can help health care professionals and parents decide what intervention and/ or preventive measures should be undertaken to ensure the best possible outcomes, as the development of successful obesity prevention strategies should rely on evidence-based information. Nonetheless, future research examining the issue of factors influencing the metabolic health of children, as well as these outcomes later in life, is crucial. Well-planned studies including a large number of individuals, as well as longitudinal research, will be particularly beneficial in this regard.

Social inequalities in obesity and overweight: secular changes in Poland between 1983 and 2020.

BACKGROUND: Human development is strongly influenced by environmental factors, including the socioeconomic status (SES) of the family. The aim of this study is to analyze the prevalence of excess body weight among Polish children and adolescents from families of varying SES examined in 1983 and 2020. METHODS: The study group included 3-15-year olds from two cross-sectional surveys (1983 and 2020) conducted in kindergartens and schools. The 1983 cohort consisted of 3394 individuals and the one from 2020-of 1253 children and adolescents. Body height and weight were measured and body mass index was calculated. Inclusion into underweight, normal weight and overweight/obese categories was based on Cole's cutoff points. SES was established based on the place of the parents' birth, parents', education status and the number of children in the family, which were self-reported in a questionary by the parents of the examined individuals. RESULTS: The mean overall SES was higher in the 2020 cohort, in comparison to the one examined in 1983. This change was also reflected by the changing prevalence of excess body weight, which, in 1983 was the greatest in the high socioeconomic category. On the other hand, in 2020 overweight/obesity was the most prevalent among individuals from families of low SES. CONCLUSIONS: The present results confirm the findings obtained in other countries, which suggest that changing the level of socioeconomic development modifies the changes regarding the prevalence of excess body weight. It is an important observation because a study of this type has not yet been conducted in the Polish population.

Changes in the prevalence of overweight/obesity and adiposity among pre-school children in Kraków, Poland, from 2008 to 2018.

Socioeconomic changes occurring over time influence the lifestyle choices of a population, and these can significantly affect children's body weight and composition. The aim of this study was to assess the changes in prevalence of overweight, obesity and adiposity in pre-school children in Poland between 2008 and 2018. Body height, body weight and subscapular and triceps skinfolds were measured in 2167 children aged 3-7 years from Kraków. Body mass index and adiposity (percentage body fat, %BF) were calculated for the children, who were then categorized as underweight, normal weight, overweight or obese according to Cole's cut-off points. Adiposity was categorized according to the z-scores for %BF as low (<-1), normal (-1 to 1) or high (>1). Differences between cohorts were analysed using the chi-squared test. Only the decrease in the prevalence of obesity in 5-year-old girls was found to be statistically significant. However, some overall tendencies were noted. Decreases in the prevalence of underweight, overweight and obesity were observed for both sexes, as well as in the incidence of high adiposity in boys and low adiposity in girls. Increases in the prevalence of high adiposity in girls and low adiposity in boys were also noted. There was no significant change in the prevalence of overweight and obesity among pre-school children over the study decade, and the visible tendencies included decreases in the prevalence of excess body weight and adiposity as well as underweight and low body fat. Also, the visible trends in adiposity were mostly negative. Further studies should, however, also consider the levels of physical fitness and activity of children, as these have a crucial influence on the measured characteristics.

BMI and adiposity based approach to obesity: the need for ethnic specificity. A reply to Kapoor et al. (2019).

The ethnicity of the studied group is one of the key characteristics that should be taken into consideration when analysing the problem of overweight and obesity. It is especially crucial in populations of countries such as India, where the proportion of the fat to lean mass and general adiposity are significantly different from those observed among Europeans. This can cause a higher risk of various metabolic-related diseases to appear at relatively lower absolute adiposity. Therefore, there is a need for further research regarding the issues of body mass and composition in Indian populations, to obtain additional information as well as to develop ethnically specific cut-off points.

Anthropometric variations in different BMI and adiposity levels among children, adolescents and young adults in Kolkata, India.

The objective of the study was to analyse selected anthropometric features of children, adolescents and young adults from middle-class families in Kolkata, India, by BMI and adiposity categories. Standardized anthropometric measurements of 4194 individuals (1999 male and 2195 female) aged 7-21 were carried out between the years 2005 and 2011. The results were compared by BMI and adiposity categories. Statistical significance was assessed using two-way-ANOVA and linear regression analysis was performed. The study population could be differentiated in terms of BMI and adiposity categories for all examined anthropometric characteristics (p ≤ 0.001). After taking age into consideration, differences were observed for males in the case of body height and humerus breadth in BMI and adiposity categories, and for femur breadth in the case of adiposity categories. For females, differences were noted in body height measurements in BMI and adiposity categories, a sum of skinfold thicknesses in BMI categories, and upper-arm and calf circumferences in adiposity categories. The patterns of differences in the BMI categories were found to be similar to those in adiposity categories. The linear regression analysis results showed that there was a significant relationship between BMI and body fat ratio in the examined population. Underweight individuals, and those with low adiposity, were characterized by lower extremity circumferences and skeletal breadths. These features reached highest values in overweight/obese persons, characterized by high body fat. However, the differences observed between each BMI and adiposity category, in most cases, were only present in early childhood.

Intergenerational changes in limb circumferences in children and adolescents aged 3-18 from Kraków (Poland) from 1983 to 2010.

OBJECTIVES: Measurements of body circumferences are often used in anthropology. The research on this topic, however, rarely concerns limb girths or secular trends. The main aim of this study was to investigate the occurrence of secular trends in selected limb circumferences among children and adolescents. METHODS: The research was based on measurements from two cross-sectional studies carried out in 1983 and 2010 with children and adolescents aged 3-18 from Krakow, Poland. The circumferences of the arm, forearm, thigh and calf, as well as the sum of circumferences and selected indicators, were analyzed. The series were compared using the two-way anova test. RESULTS: In most age groups of both sexes, a positive secular trend was observed for the majority of studied traits. The exception was the thigh circumference, for which, among girls, measurements in both series were similar, and negative intergenerational changes were recorded in the youngest age groups of both sexes as well as among the oldest girls. Most observed discrepancies were statistically significant in pre-school children and adolescents. CONCLUSIONS: The presence of positive secular trends shows that limb circumferences were increasing in subsequent generations, especially in boys. Contemporary girls, particularly in the older age groups, were more determined to have a slim figure and practiced conscious weight control. Summarizing, observed tendencies resulted from the improvement of socio-economic conditions, but were also related to the low level of physical activity.

Intergenerational changes in chest size and proportions in children and adolescents aged 3-18 from Kraków (Poland), within the last 70 years.

OBJECTIVES: The size and proportions of the human body change continuously in response to social change and economic development. As reported by papers on intergenerational changes in chest size, this part of the human body is also influenced by environmental factors. The aim of this study was to assess changes in the dimensions and proportions of the chest of children and adolescents over a span of 70 years. METHODS: In 2010 an anthropological study was conducted on 3878 children and adolescents aged 3-18 years living in Kraków (Poland). Data on chest dimensions (breadth, depth, circumference, chest index) were compared to data from 1938 (3719 children) and 1983 (6464 children). RESULTS: In boys, chests became increasingly deep; in boys 18 years of age, the chest index increased by 4.8 units, unlike girls, whose chests markedly flattened. The chest index in girls 18 years of age decreased by 4.2 units. In almost all age categories these differences were statistically significant. Also, in all age categories, children studied in 2010 had a significantly bigger chest circumference than boys and girls surveyed in 1983, respectively, by averages of 3.6 cm and 3 cm. CONCLUSIONS: The main reason for these changes may be the socio-economic transformation, which has been especially strong in recent decades. These results may have practical importance in many areas of knowledge, including medicine, nutritional science, and sports. They can also be important for informing preventive measures that should be taken in order to increase the physical activity of children and youth, especially boys.