Secular trends in body composition for children and young adults: the Fels Longitudinal Study

Changes in Anthropometric Measurements and Physical Fitness of Polish Students in 20-Year Period

BACKGROUND

Intergenerational changes are still being recorded worldwide, although their magnitude and direction may vary in different countries. The aim of this study was to determine changes in the magnitude and direction of changes in the body morphology and motor abilities of physically active adults over 20 years.

METHODS

Two hundred and fifty-two individuals aged 18-28 years volunteered to participate in the study. The changes were analyzed over a 20-year period (March 2001; P₁ vs. March 2022; P₂). The measured parameters were body height, weight, and body fat. Further, hand grip strength with dynamometer measurement, a sit-up test, a sit and reach test, and a standing long jump were performed to examine motor abilities. The results of the conducted tests were compared between subjects from both periods.

RESULTS

Our study confirms changes in trends concerning body morphology and motor ability performance. Higher values of body mass index and body fat were observed in P₂ women, whereas these differences were not significant in men. Additionally, in terms of physical performance, the P2 group noted worse results than their peers from the past.

CONCLUSION

Despite young adults claiming to have similar physical activity levels to those observed in the past, they demonstrate poorer physical performance and higher body fat levels. The observed changes can be considered negative.

Region-related patterns of the main physical development indicators observed in northerners in the ontogenetic aspect

Indicators of physical development appear to be environmentally sensitive and thus we can consider them the main characteristics of the population health.The aim. To assess the line of physical development main variables in the ontogenetic aspect (data from the North born male subjects aged from 8 to 77).Material and methods. Three thousand seven hundred and ninety-four male Caucasians from 17 age groups were examined to analyse their physical development.Results. The study showed longer body length variables as the region-related somatometric picture which is characteristic of male Caucasian northerners in comparison with those from other regions of the Russian Federation, as well as from other countries. Besides, they exhibited significantly lower body mass index and reported to have had lower body weight since the age of 17. We can see the modern northerners’ somatotype being influenced by regional extremes. That also includes the end of the body growth processes by the start of ontogenesis in the youth. The line pattern of annual growth observed in the body length and weight variables indicates a combined pronounced dynamics in the 11 to 16 age period. By the age of 60–77 years subjects tend to decrease in the body length with a significant increase in the body weight and body mass index by the age of 31–36.Conclusion. The study suggests that identifying risks for the development of noninfectious and cardiovascular diseases caused by accelerated BMI in older populations requires monitoring of the North inhabitants’ main physical development indicators as well as the body annual growth variables.

Recommendations for Resuming PA after Prolonged Rest in Children and Adolescents: A Systematic Integrative Review of Relevance for Immunity

This systematic integrative review aims to summarize the protective effect of PA on children and adolescents, with special reference to the immune system. Periods of prolonged inactivity in children and adolescents are rare and due to exceptional events, such as illness or environmental circumstances, e.g., natural disasters, wars, or epidemics. The recent COVID-19 pandemic forced billions of children in developmental ages into inactivity. This exceptional event was the reason for studying the compensational behavioral strategies adopted by children and adolescents to counteract physical inactivity. Several studies showed the rise of spontaneous physical activity (PA) among children and adolescents to compensate for sedentarism. However, for some children, sedentarism could in turn foster other sedentarism. With the restart of "normal daily life" worldwide, a question is posed on both how to resume PA without causing damage and how to improve the immune response. Some key points emerged from the literature. Children must resume PA gradually using different methods, considering age, sex, health status, and the presence of overweight conditions. Immunity can be stimulated with PA by aerobic exercise, resistance training, flexibility exercise, relaxation, and coordinative exercises.

Changes in the body mass index and blood pressure association across time: Evidence from multiple cross-sectional and cohort studies

Although body mass index (BMI) is considered a key determinant of high blood pressure, its importance may differ over time and by age group. We utilised separate data sources to investigate temporal changes in this association: 23 independent (newly sampled), repeated cross-sectional studies (Health Survey for England (HSE)) at ≥25 years (1994-2018; N = 126,742); and three British birth cohorts at 43-46 years (born 1946, 1958, and 1970; N = 18,657). In HSE, associations were weaker in more recent years, with this trend most pronounced amongst older adults. After adjustment for sex, anti-hypertensive treatment and education, the mean difference in systolic blood pressure (SBP) per 1 kg/m² increase in BMI amongst adults ≥55 years was 0.75 mmHg (95%CI: 0.60-0.90) in 1994, 0.66 mmHg (0.46-0.85) in 2003, and 0.53 mmHg (0.35-0.71) in 2018. In the 1958 and 1970 cohorts, BMI and SBP associations were of similar magnitude yet weaker in the 1946 cohort, potentially due to differences in blood pressure measurement device. Quantile regression analyses suggested that associations between BMI and SBP were present both below and above the hypertension threshold. A weaker association between BMI and blood pressure may partly offset the public health impacts of increasing obesity prevalence. However, despite sizable increases in use of antihypertensive medication, BMI remains positively associated with SBP in all ages. Our findings highlight the need to tackle non-medical factors such as population diet which influence both BMI and blood pressure, and the utility of using multiple datasets to obtain robust inferences on trends in risk factor-outcome associations across time.

Socioeconomic position and body composition in childhood in high- and middle-income countries: a systematic review and narrative synthesis

BACKGROUND

The relation between socioeconomic position (SEP) and obesity measured by body mass index (BMI), a measure of weight for height, has been extensively reviewed in children, showing consistent associations between disadvantaged SEP and higher BMI in high-income countries (HICs) and lower BMI in middle-income countries (MICs). Fat mass (FM), a more accurate measure of adiposity, and fat-free mass (FFM) are not captured by BMI, but have been shown to track from childhood to adulthood, and be important for cardiovascular health and functional outcomes in later life. It is not clear whether body composition is associated with SEP. We systematically reviewed the association between SEP and body composition in childhood.

METHODS

A systematic review was carried out following PRISMA guidelines. The protocol was pre-registered with PROSPERO (CRD42019119937). Original studies in the English language, which examined the association between SEP and body composition in childhood, were included. An electronic search of three databases was conducted. Two independent reviewers carried out screening, data extraction and quality assessment. Due to heterogeneity in results, a narrative synthesis was conducted. Heterogeneity in findings according to SEP, sex, body composition measure and country income level was investigated.

RESULTS

50 papers were included, the majority from HICs. No papers were from low-income countries. Disadvantage in childhood was associated with greater FM and lower FFM in HICs, but with lower FM and lower FFM in MICs. When measures of FFM indexed to height were used there was no evidence of associations with SEP. In HICs, more studies reported associations between disadvantaged SEP and higher FM among girls comparative to boys.

CONCLUSIONS

Inequalities in FM are evident in HICs and, in the opposite direction, in MICs and follow similar trends to inequalities for BMI. Inequalities in height are likely important in understanding inequalities in FFM.

Variability of Body Build and Physiological Spinal Curvatures of Young People in an Accelerated Longitudinal Study

The human body is characterized by the variability of the characteristics of body build, which is expressed in the instability of spinal curvatures, which change during ontogeny. This phenomenon leads to a phylogenetic evolution of the human body build and posture. The aim of the study was to assess the dynamics of the variability of traits and indices of body build and posture and their mutual relations. It was assumed that over the 10-year observation period, a significant variability and relationships will be observed between the characteristics of body build and posture in young adults. Between 2006 and 2016, 2154 women and men aged 19.6 ± 0.8 were examined (first-year students at the University of Economics in Katowice, Poland). Measurements of basic anthropometric measurements and angular values of lumbar lordosis and thoracic kyphosis were performed. The collected data were analysed statistically, and the intergroup and intragroup differences were evaluated (ANOVA with repeated measures). The dynamics of variability (by building time series) and absolute and single-base increments were determined. The body build of young men and women in the period of ontogenetic stabilization in the study group has changed statistically significantly over the decade. A prediction of the increases in body weight and hip circumference was recorded over a period of 10 years, especially in men. The characteristics of body posture have also undergone a significant progressive change. In women, thoracic kyphosis increased by 96.15%, whereas in men, lumbar lordosis decreased by 52.65%. Significant sexual differentiation was shown for such characteristics as body height, waist circumference and the angle of lumbar lordosis. The relationships between the characteristics of body build and posture were verified. There was a moderate relationship between the hip circumference and lumbar lordosis in women and a weak relationship between body height and the angle of thoracic kyphosis in men.

Normative Values of Height, Bodyweight and Body Mass Index of 12-17 Years Population from Extremadura (Spain)

Background: Growth charts constitute an essential tool for monitoring adolescents' development. In Extremadura, the percentile growth charts by Faustino Orbegozo Foundation are used. However, they are based on Basque Country population data. Considering socioeconomic differences between Spanish regions, growth chart data could not be appropriate. Aims: to describe the percentile distribution of adolescents from Extremadura and compare these percentiles with those proposed by the Faustino Orbegozo Eizaguirre Foundation that are currently applied in the Extremadura Health Service. Methods: A descriptive cross-sectional study was conducted. A total of 4130 adolescents (12-17 years) participated into the study. Bodyweight and height were assessed. Results: Significant differences were found comparing real measured values with commonly used reference tables for bodyweight at all ages between 12 and 13 years and at 14 years in both gender (p < 0.05). Differences were also found in boys at 15, 16.5 and 17 years (p < 0.05). Regarding height, significant differences were reported at 12, 13, 14.5, 15, 16.5 and 17 years old (p < 0.05) in males; while females' results only revealed differences at 12, 12.5, 14.5 and 15.5 years (p < 0.05). BMI outcomes showed differences in both gender at 12, 12.5, 13, 14 and 15 years old (p < 0.05). Differences were also found at 16 and 14.5 years for boys and girls, respectively (p < 0.05). Conclusion: Bodyweight, height and BMI of adolescents from Extremadura differ of the reference values currently applied. Hence, this study's outcomes suggest the need to use new indicators, adapted to the physical and anthropometric reality of children and young people to avoid the possible normalisation of situations of thinness, overweight or obesity.

Anthropometric measurements of school-going-girls of the Punjab, Pakistan

BACKGROUND

Child's growth has been considered an important indicator to evaluate health trends in a population and to devise strategies accordingly. The purpose of the present study was to determine most commonly occurring weight abnormalities among school-going girls from Punjab and to compare with international growth references devised by World Health Organization (WHO) and Centre for Disease Control and Prevention (CDC).

METHODS

In this cross-sectional study a sample of 10,050 child and adolescent girls from 12 districts, 35 public/private sector schools, located in rural, semi-urban and urban areas of northern, central and southern Punjab were included. Parameters were measured according to standardised techniques and centile curves obtained by Lambda, Mu, Sigma (LMS) method.

RESULTS

The results showed an increase in weight, height and BMI of the Punjabi girls until 15 years. When compared with international growth references, weight and BMI in our population were significantly lowered; however, height was lower during 12-16 years of age and the differences observed were more pronounced with CDC as compared to WHO. When 3rd, 50th and 90th percentiles of weight, height and BMI in our population were compared with international standards, the values were lower in our paediatric population.

CONCLUSION

The Punjabi schoolgirls significantly differed from CDC and WHO references, and this difference should be taken into consideration for evaluation of growth abnormalities in our paediatric population. However, in the absence of national reference data, WHO standards have been considered more appropriate for comparison.

Prenatal exposure to di-(2-ethylhexyl) phthalate and decreased skeletal muscle mass in 6-year-old children: A prospective birth cohort study

BACKGROUND/AIM

Phthalate is a well-known endocrine-disrupting chemical that has anti-androgenic effects. Although there are several studies on the relationship between body composition and phthalate, studies that investigated the effects of phthalate on skeletal muscle during childhood are lacking.

METHODS

We analyzed data from 481 mother-and-child pairs enrolled in the Environment and Development of Children cohort in South Korea. We examined the association between phthalate metabolites (mono [2-ethyl-5-hydroxyhexyl] phthalate [MEHHP], mono [2-ethyl-5-oxohexyl] phthalate [MEOHP], molar sum of MEHHP and MEOHP [Σ DEHP], and mono-n-butyl phthalate [MnBP]) in prenatal maternal urine and children's urine at the age of 6, and body composition indices (body mass index [BMI] z-score, percentage of fat mass, fat mass index, percentage of skeletal muscle, and the skeletal muscle index [SMI]) measured when the child was 6 years using a bioelectrical impedance analyzer.

RESULTS

A 2-fold increase in Σ DEHP and MnBP in the prenatal maternal urine was significantly associated with a -0.07 unit (95% CI: -0.11, -0.03) and -0.09 unit (95% CI: -0.14, -0.03) change in SMI, respectively, in 6-year old girls alone. BMI z-score was also negatively associated with a 2-fold increase in MEHHP and MnBP in prenatal maternal urine as -0.11 unit (95% CI: -0.22, -0.01) and -0.15 unit (95% CI: -0.28, -0.02) change, respectively, only among girls. Among boys, phthalate metabolites in the prenatal and children's urine were not significantly associated with any body composition indices.

CONCLUSIONS

Our longitudinal study shows that high levels of prenatal exposure to phthalates are significantly associated with decreased SMI among girls. We can postulate that anti-androgenic effects of phthalates during pregnancy may affect girl offspring's muscle growth.

Socioeconomic position and body composition across the life course: a systematic review protocol

INTRODUCTION

The relation between socioeconomic position (SEP) and obesity measured by body mass index (BMI) has been extensively reviewed, but there is less research on the association between SEP and body composition. Fat distribution and muscle quality have been linked to adverse health outcomes such as cardiovascular disease, diabetes and poor physical capability. There is some evidence of secular changes in body composition with increasing fat-mass and reducing muscle quantity and strength, but it is unclear whether there have been secular changes in social inequalities in body composition. The aim is to perform a systematic review of the existing literature on the association between SEP and body composition and to explore any secular changes.

METHODS

The systematic review will be carried out according to PRISMA guidelines. An electronic search of MEDLINE and Embase Classic + Embase will be conducted using OvidSP as the database interface, as well as SPORTDiscus using EBSCO. Two independently working reviewers will initially screen abstracts to exclude papers that are clearly ineligible, followed by a full-text screening to exclude papers not meeting all inclusion criteria. Any disagreements will be resolved through discussion. Data extraction and quality assessment of eligible papers will be carried out by 2 reviewers using a standardised form. The reference lists of identified papers will be searched for additional papers. Original studies in the English language, which examine the association between SEP at any age and body composition at the same or later age will be included if they use any recognised measures of SEP (e.g. income, occupation, over-crowding) and a recognised measure of body composition (total, proportional or location of fat mass and fat-free mass, using any appropriate methods, excluding anthropometry). Due to expected heterogeneity, a narrative synthesis is expected, with a descriptive summary to be provided in tables. If there is consistency in reporting of associations, a random-effects meta-analysis will be used to provide an overall summary estimate.

DISCUSSION

The results of the review will summarise the existing evidence on social inequalities in body composition. Findings will identify gaps in knowledge and where further research is required.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42019119937.

Secular trends in body height, body weight, BMI and fat percentage in Polish university students in a period of 50 years

Objectives

The aim of the study was to determine changes in the magnitude and direction of secular trends in body height, body weight, body mass index (BMI) and fat percentage in university students from a university of technology and a university of physical education in a period of 50 years.

Methods

The data were derived from the examinations of male students from the Warsaw University of Technology, conducted four times, in 1959, 1971, 1994, 2011, and male students from the Józef Piłsudski University of Physical Education in Warsaw, who were examined in 1963, 1972, 1996, and 2012. Body height, body weight and thickness of 2 skinfolds (triceps skinfold and abdomen skinfold) were measured. Body mass index (BMI) and fat percentage (FAT%) were also calculated.

Results

Current university students are taller and heavier than their peers from the previous decades, with BMI remaining within the reference range. A substantial increase in fat percentage was found in both groups. Over the period of fifty years, mean fat percentage in students from the university of technology increased by 6.3% (F1,3 = 116.56, p < 0.001, η² = 0.3736), whereas this increase in the students from the university of physical education rose by 3.5% (F1,3 = 72.94, p < 0.001, η² = 0.3181).

Conclusion

Changes in secular trends in the students from both universities are likely to be linked to the dynamic economic and systematic transformation in Poland observed in the period of the last 50 years. The period of economic transformations in the last decade was more conducive to physical development of university students than the previous period of economic crises.

Longitudinal assessment of body composition in healthy Swedish children from 1 week until 4 years of age

BACKGROUND/OBJECTIVES

Knowledge of longitudinal body composition development is required to identify the mechanisms behind childhood overweight and obesity and to prevent these conditions. However, accurate data on this development in early childhood are lacking. Our aim was to describe the longitudinal body composition development in healthy young Swedish children.

SUBJECTS/METHODS

Body size and composition were assessed in 26 children using air-displacement plethysmography (1 and 12 weeks and 4.4 years of age) and isotope dilution (1.5 and 3 years of age) and compared with available reference data.

RESULTS

Body fat (%) for boys (n=16) was 12.8±3.9 (1 week), 25.6±4.8 (12 weeks), 28.2±3.8 (1.5 years), 27.3±5.1 (3 years) and 26.1±3.5 (4.4 years). For girls (n=10) these values were 15.3±2.9, 25.7±3.9, 27.9±3.3, 26.3±7.2 and 26.0±5.3, respectively. These values were above the Fomon reference values at 1.5 years of age and later and higher than the Butte reference (P<0.05) for boys at 1.5 years of age. At all ages the coefficients of variation were higher for body fat (%) (12-30%) than for BMI (4-11%).

CONCLUSIONS

At 4 years of age our children had more body fat than indicated by reference data. This high level may have already been established at 1.5 years of age but our small sample and the lack of appropriate reference data limit the possibility of drawing firm conclusions. Our results demonstrate the limitations of BMI when investigating overweight and obesity in early life and highlight the need for appropriate reference body composition data in infants and young children.European Journal of Clinical Nutrition advance online publication, 23 August 2017; doi:10.1038/ejcn.2017.125.

Body composition changes in male patients with chronic obstructive pulmonary disease: Aging or disease process?

BACKGROUND

Chronic obstructive pulmonary disease (COPD) mainly affects middle-age and elderly adults. It is unclear if the presence of muscle wasting and fat accumulation in patients with COPD is age or disease-related. This study investigated the effect of age and COPD disease severity on body composition with the aim of identifying a biomarker(s) for COPD.

METHODS

Healthy subjects and patients with COPD of different severity were recruited. Dual-energy X-ray absorptiometry was used to analyze total and segmental body composition. Subjects included in the analysis were classified into four groups: healthy young (aged 20-45 years) (n = 35), healthy old (aged ≥ 60 years) (n = 37), moderate COPD (n = 40), and severe COPD (n = 14).

RESULTS

In healthy old adults, leg and limb lean masses were lower by 10.6% and 8.5%, respectively, compared with healthy young adults (P < 0.05). Appendicular lean outcomes were significantly lower in the moderate COPD compared to the healthy old group and were significant lower in subjects with severe COPD compared to those with moderate COPD. All fat depots were similar for both young and old healthy subjects and subjects with moderate COPD, but significantly decreased in patients with severe COPD.

CONCLUSIONS

This study examined the changes in total and segmental body composition with aging and COPD severity. It found that aging and COPD altered the body composition differently, and the effect was most pronounced in leg lean mass. Remarkably, differences in appendicular lean masses were seen in mild COPD although no changes in body weight or BMI were apparent compared with healthy young adults. In contrast, fat depot changes were only observed in severe COPD. Aging and COPD processes are multifactorial and additional longitudinal studies are required to explore both the quantitative and qualitative changes in body composition with aging and disease process.

Body mass index associations between mother and offspring from birth to age 18: the Fels Longitudinal Study

BACKGROUND

Parental obesity is a known determinant of childhood obesity. Previous research has shown a strong maternal influence on body mass index (BMI) during infancy and early childhood.

OBJECTIVES

The purpose of this research was to investigate the BMI associations between mother and offspring from birth to age 18 years.

METHODS

Participants were selected from the Fels Longitudinal Study. The current study sample includes 427 (215 mother/son and 212 mother/daughter) mother/child pairs. These pairs are repeatedly measured at multiple age groups in children, resulting in a total of 6,263 (3,215 mother/son, 3,048 mother/daughter) observations for data analysis. Inclusion criteria were children with measured height and weight for BMI collected at ages 0 to 18 years and their mother with BMI data. Maternal influences of BMI on offspring BMI from birth to early adulthood were analyzed by Spearman correlations and linear regression analyses.

RESULTS

Mother/son BMI correlations became statistically significant (p ≤ 0.05) at age 5-6 years and were significant through puberty and into early adulthood at age 18 years. Mother/daughter correlations became significant at age 1.5 years and also continued through adolescence, puberty and early adulthood at age 18 years. Associations persisted after the study sample was grouped into life stages and adjusted for decade of birth and parity.

CONCLUSIONS

The mother/daughter relationship was more strongly correlated than the mother/son relationship and also became statistically significant at an earlier age than boys.

Peak Bone Mass and Patterns of Change in Total Bone Mineral Density and Bone Mineral Contents From Childhood Into Young Adulthood

The literature has not reached a consensus on the age when peak bone mass is achieved. This study examines growth patterns of total bone mineral content (TBMC) and total bone mineral density (TBMD), peak bone mass, effect of concurrent anthropometry measures, and physical activity on growth patterns in a sample of 312 white males and 343 females aged 8-30 yr. We analyzed data from participants enrolled in Fels Longitudinal Study. Descriptive analysis was used to ascertain characteristics of participants and growth patterns of TBMC and TBMD. Mixed effects models were applied to predict ages at attainment of peak TBMC and TBMD and assess the effects of height, weight, body mass index (BMI), and habitual physical activity on the attainment. Significant differences between sexes were observed for measures of TBMC and TBMD, and differences varied with age. For females, predicted median ages at peak TBMC and TBMD attainments are 21.96 yr (interquartile range [IQR]: 21.81-22.21) and 22.31 yr (IQR: 21.95-22.59), respectively. For males, predicted median ages are 23.34 yr (IQR: 24.34-26.19) and 26.86 yr (IQR: 25.14-27.98) respectively. For females, height, weight, and BMI, but not physical activity, had significant influences on attainment of TBMC and TBMD (p<0.01). For males, weight and BMI, but not height and physical activity, exerted significant influence on attainment of TBMC and TBMD (p<0.01), and also modified correlations between age and peak TBMC and TBMD. Our results suggest that (1) for both sexes, trajectories of TBMC and TBMD follow a curvilinear pattern between ages 8 and 30 yr; (2) predicted ages at peak TBMC and TBMD are from early to late 20s for both white males and females, with females reaching their peaks significantly earlier than males; and (3) concurrent height, weight, and BMI, but not habitual physical activity, exert significant effects on trajectories of TBMC and TBMD.

Impact of lifestyle factors on trends in lipid profiles among Korean adolescents: the Korea National Health and Nutrition Examination Surveys study, 1998 and 2010

Purpose

Only a few studies have explored nationwide trends in lipid profiles among Asian adolescents. We aimed to assess trends in lipid profiles and the associated lifestyle factors among Korean children.

Methods

We analyzed data for 2,094 adolescents who were aged 10–18 years and had participated in the Korea National Health and Nutrition Examination Surveys in 1998 and 2010.

Results

During 1998–2010, the prevalence of obesity significantly increased in boys, but no changes were observed in girls. Over this period, there was a small but significant decrease in the mean low-density lipoprotein (LDL)-cholesterol level in boys (1998, 87.5 mg/dL; 2010, 83.6 mg/dL; P=0.019) and mean triglyceride levels in girls (1998, 90.8 mg/dL; 2010, 85.8 mg/dL; P=0.020). There were no significant changes in the prevalence of dyslipidemia in boys, but a modest decrease was noted in girls (1998, 25.1%; 2010, 18.3%; P=0.052). During the study period, the prevalence of breakfast skipping decreased, whereas that of regular exercise increased in both groups. Daily total energy intake did not change between these years. In multivariable logistic regression analyses, breakfast skipping was associated with increased risk of hyper-LDL-cholesterolemia in boys (odds ratio [OR], 5.77) and hypertriglyceridemia (OR, 2.27) in girls. Regular exercise was associated with decreased risk of hypo-HDL-cholesterolemia (OR, 0.40) in boys.

Conclusion

Although the prevalence of obesity in boys increased, favorable or constant trends in lipid profiles were observed among Korean adolescents during 1998–2010. Decrease in breakfast skipping and increase in regular exercise may have contributed to these trends.

Changes in abdominal obesity in Chilean university students stratified by body mass index

Background

Studies based on Body Mass Index (BMI) and waist circumference (WC) are generally used to examine the prevalence and tendency of overweight and obesity. These studies help determine the socioeconomic development of a country and improve public health policies. Therefore, the goal of this research was to determine the trend of change in abdominal obesity of Chilean university students according to the Body Mass Index (BMI) measured in intervals of three and six years.

Methods

For this study, a total of 1598 students of both sexes ranging in age from 18 to 26 from a Chilean university were evaluated. Students were assessed commencing in 2007 (372 males and 315 females), 2010 (250 males and 330 females), and ending in 2013 (153 males and 178 females). During the three transversal assessments, weight, height, and waist circumference were evaluated. BMI was calculated for both sexes.

Results

No significant differences were found in age and BMI during the three years evaluated (2007, 2010, and 2013). In 2013, waist circumference (WC) increased significantly (p < 0.001 for both sexes). Moreover, in 2013, in all the percentiles evaluated, high values of WC were compared in relation to previous years. Furthermore, in 2013, in all four BMI categories (underweight, normal, overweight, and obese), the university students showed significant increases in WC (Females: p = 0.004; Males: p = 0.035) whereas in 2007 and 2010, the values remained relatively stable.

Conclusions

BMI remained constant during 2007, 2010, and 2013. However, the university students of both sexes showed greater risk of abdominal obesity as a result of increased WC in 2013.

Overweight trends among Polish schoolchildren before and after the transition from communism to capitalism

This study aims to reveal the secular trends in body mass index (BMI) and the prevalence of overweight and obesity among Polish schoolchildren between the years 1966-2012, during which intense socio-political changes took place. Four surveys were conducted in several districts of Poland looking at 69,746 schoolchildren aged 7-18. Significant increase in mean BMI as well as in the prevalence of overweight and obesity was observed. During this time the highest increase in both mean BMI and excess weight was observed between 1988 and 2012, i.e. after the political transformation, resulting in the improvement of living conditions. However, with respect to girls in late adolescence, between these years, the mean BMI as well as the prevalence of overweight were leveling off, while the percentage of boys with excess body fat in the same developmental category significantly increased in 2012. In the years 1966-1978 and 1978-1988 the pattern of changes in the prevalence of overweight and obesity reflected the social and economic circumstances, i.e. temporary economic improvements, or deepening political crises and food shortage. In conclusion, the weight status of schoolchildren strongly reflects socio-political changes that took place in Poland, as well as in most of the Central European countries in the last half century.

Time trends in BMI, body fatness, and adiposity rebound among boys from Kraków (Poland) from 1983 to 2010

OBJECTIVES

The prevalence of childhood obesity has been increasing during the last decades in many countries, but less is known about secular trends in growth curves covering the whole childhood span. The main purpose of this study was to explore changes in body weight, height, BMI, percent body fat (%BF), adiposity rebound (AR), and pubertal timing in boys from Kraków between 1983 and 2010.

METHODS

Totally, 4,986 boys (3-18 years) were measured during cross-sectional studies. Using the results of height, weight, and skinfold measurements, BMI and %BF were calculated. The LMS method was used to construct BMI and %BF percentiles. Three cut-off points were distinguished in individual age groups of the subjects-below the 15th percentile, 50th percentile, and above the 85th percentile. The mean age at pubarche was calculated by the probit method.

RESULTS

The boys from 2010 were taller and heavier than the boys from 1983. Before the time of AR, boys from 2010 had lower BMI, but after AR had higher BMI than boys from 1983. An earlier AR appeared in all BMI 2010 percentile curves as compared to 1983. The boys from 2010 also showed an acceleration of sexual maturation and earlier Tanner Stage II, equaling 11.80 years.

CONCLUSIONS

In boys from 2010, AR occurs earlier than in boys from 1983. Changes in timing of AR cannot be explained only by changes in degree of body adiposity. Early AR could be a marker of the acceleration of development.

Secular change in cardiorespiratory fitness and body composition of women: the Aerobics Center Longitudinal Study

OBJECTIVE

To investigate secular change of cardiorespiratory fitness (CRF) and body composition during 35 years in a large sample of women enrolled in the Aerobics Center Longitudinal Study.

PATIENTS AND METHODS

A cross-sectional analysis of baseline fitness data collected during preventive medical examination of 13,037 women aged 20 to 64 years evaluated at the Cooper Clinic in Dallas, Texas, from January 1, 1970, through December 30, 2004, who underwent a body composition assessment and a maximal treadmill exercise test. Women were stratified by examination year (5 years for each group) and age. Analysis of covariance was used to ascertain secular change of CRF and body composition.

RESULTS

Adjusted CRF levels, as indicated by maximal metabolic equivalent or relative maximum oxygen consumption, among women in the cohort increased significantly during a 35-year period for both age groups (P<.001). The greatest change occurred during the 1970s to 1980s, with a small decrease in 2000 through 2004 in both age groups. Adjusted body mass index increased 9.05% during the past 35 years (P<.001), but adjusted percentage of body fat was significantly higher in 1980 through 1984 than in the other groups (P<.001).

CONCLUSIONS

In a large cohort of women, the mean CRF has improved during the past 35 years, with a slight decrease in 2000 through 2004. From 1980 through 2004, the increase in body weight was mainly attributable to the increase in fat-free mass.

[Contribution of anthropometric characteristics to pubertal stage prediction in young male individuals]

OBJECTIVE

To identify the contribution of anthropometric variables to predict the maturational stage in young males.

METHODS

Cross-sectional study that enrolled 190 male subjects aged between eight and 18 years, randomly selected from public and private schools in Natal, Northeast Brazil. Thirty-two anthropometric variables were measured following the recommendations of the International Society for the Advancement of Kineanthropometry (ISAK). The assessment of sexual maturation was based on the observation of two experienced experts, who identified the pubertal development according to Tanner guidelines (1962).

RESULTS

The anthropometric variables showed a significant increase of their values during the advancement of pubertal development (p<0.05). The following variables showed the best value for prediction of maturational groups: sitting height, femoral biepicondylar diameter, forearm girth, triceps skinfold, tibiale laterale and acromiale-radiale bone lenghts. These variables were able to estimate the pubertal stages in 76.3% of the sujects.

CONCLUSION

The anthropometric characteristics showed significant differences between the moments of maturational stages, being found, representatively, seven variables that best predict the stages of sexual maturation.

Age as a moderator of the secular trend for grip strength in Canada and the United States

PURPOSE

To determine whether grip strength changed on average over recent decades at each of two age levels (children and adolescents versus adults) in Canada and the US.

METHODS

For each sex, weighted least squares regression analyses were performed on mean grip strength values as reported in studies conducted from the 1960s onwards.

RESULTS

Grip strength did not change significantly as a function of year tested in children and adolescents, whereas it declined as a negatively accelerated function of year tested in adults.

CONCLUSION

The results are contrary to what might be expected given that body weight has increased in both countries in recent decades and given that grip strength has been found to be positively correlated with body weight. It is suggested that there was a concurrent change in a factor that operated to counteract the effect of increased body weight on grip strength, a prime candidate being a decrease in levels of serum vitamin D. It is also suggested that the secular decline in adult grip strength can be explained by a factor that affects muscular function but which has a long latency period, a prime candidate here being obesity history.

Secular trends in the fat and fat-free components of body mass index in children aged 8-18 years born 1958-1995

BACKGROUND

It is unknown whether the secular trend in childhood BMI reflects increases in fat-free mass as well as fat mass.

METHODS

This study decomposed BMI trends in 488 participants in the Fels Longitudinal Study born between 1958-1995 and aged 8-17.99 years into their fat and fat-free components. Generalized estimating equations estimated birth year cohort (1958-1970, 1971-1983, 1984-1995) effects on 2208 observations of BMI, fat mass index (FMI = fat mass (kg)/height (m)(2)) and fat-free mass index (FFMI = fat-free mass (kg)/height (m)(2)).

RESULTS

BMI in boys increased across cohorts, with those born between 1984-1995 being 2 kg/m(2) larger than those born between 1958-1970 (p = 0.001) and increases in FMI were highly significant (p-values < 0.001). FFMI did not differ by cohort. In girls, there was a significant advantage in BMI (1.2 kg/m(2)) and FFMI (0.8 kg/m(2)) of the 1984-1995 cohort compared to the 1971-1983 cohort (p-values < 0.05).

CONCLUSIONS

Because the long term trend in childhood BMI in boys appears to be driven by an increase in total body adiposity, evidence is provided to support current knowledge on the predicted deleterious long-term consequences of the childhood obesity epidemic in boys. Research is needed to confirm whether recent changes in BMI in girls are due to increases in fat-free mass resulting from changes in behaviour and lifestyle not yet manifest in boys.