Influence of socioeconomic factors on fitness and fatness in Spanish adolescents: The AVENA study

Elevated Risk of Overweight/Obesity-Related Markers and Low Muscular Fitness in Children Attending Public Schools in Chile

In Chile, children of low socioeconomic status usually attend public schools and have few opportunities to engage in healthy behaviors. This may increase their risk of overweight/obesity and low muscular fitness. Therefore, we aimed to determine the association between the school type attended with overweight/obesity-related markers and the muscular fitness of children in Chile. We included 1410 children (6-13 years old) attending public, subsidized, or private schools. Overweight/obesity-related markers included BMI Z-scores, waist circumference, and body fat percentage. Muscular fitness assessment included handgrip strength and standing long jump. The odds ratios [95% CI] of overweight/obesity, elevated waist circumference, elevated body fat, low handgrip strength, and low standing long jump were compared between school types. Compared with boys attending public schools, those attending subsidized or private schools had lower odds ratios of low handgrip strength (0.63 [0.42-0.94] and 0.44 [0.25-0.78], respectively). Girls attending subsidized schools, compared with those in public schools, had lower odds of overweight/obesity (0.63 [0.44-0.90]) and of having low handgrip strength (0.51 [0.34-0.78]). Compared with girls in public schools, those attending private schools had lower odds (vs. public schools) of overweight/obesity (0.45 [0.28-0.74]), of having elevated body fat (0.53 [0.29-0.96]), and of having low standing long jump (0.41 [0.21-0.77]). The elevated risk of overweight/obesity-related markers and lower muscular fitness in children, particularly girls, attending public schools increase their current and future disease risk. This suggests that childhood socioeconomic status plays a central role in determining disease risk. Health-promoting interventions specifically focused on children from disadvantaged contexts are required.

Correlations between Physical Fitness and Body Composition among Boys Aged 14–18—Conclusions of a Case Study to Reverse the Worsening Secular Trend in Fitness among Urban Youth Due to Sedentary Lifestyles

A secular trend can be observed throughout the world with an increase in childhood obesity and a decrease in fitness. The research aimed to examine the results of tests measuring the conditional abilities of young boys aged 14–18 in fitness tests and their correlations with body composition indicators. That was supported by research that has been prepared in Hungary so far. This research focuses on the results of fitness tests conducted on 14- to 18-year-old boys, presented along with body composition data. The authors sought to describe the development of the fitness profiles of males at a Budapest secondary school participating in the research, based on the results of the Hungarian National Student Fitness Test (NETFIT®), and also how their physical characteristics affect the results of NETFIT® tests in the sample measured. A total of 735 male high school students at a Budapest secondary school (14–18 years old) (mean ± SD, 16.05 ± 1.18 years) participated in the survey. The data were collected in the 2018/2019 academic year, and it was compared with the national data. The correlation between the performance indicators of the NETFIT® tests and the physical characteristic indicators was analyzed using the two-block Partial Least Squares method. In the resulting groups, Kruskal–Wallis variance analysis was performed to investigate the differences in performance. In contrast, pairs of group differences were tested with the Mann–Whitney test. Boys with a short physique were at some advantage in trunk-lifts and push-ups, compared to taller boys. It was also obvious that being overweight is a hindrance regarding the PACER test or the standing broad jump. The handgrip in the left and right hand was mostly of similar strength or weakness. Tall-heavy children performed better in this test. The grip strength of tall-thin students was also strong, but not as strong as in the tall-heavy group. Reducing the percentage of body fat (PBF) and creating the optimal BMI index is important for the younger age group, as our results have clearly demonstrated that overweight is a hindrance in the PACER, VO2 max, standing broad jump, back-saver sit-and-reach, and push-up tests.

Mediation Role of Physical Fitness and Its Components on the Association Between Distribution-Related Fat Indicators and Adolescents' Cognitive Performance: Exploring the Influence of School Vulnerability. The Cogni-Action Project

Background: Physical fitness and fatness converge simultaneously modulating cognitive skills, which in turn, are associated with children and adolescents’ socioeconomic background. However, both fitness components and fat mass localization are crucial for understanding its implication at the cognitive level.

Objective: This study aimed to determine the mediation role of a global physical fitness score and its components on the association between different fatness indicators related to fat distribution and adolescents’ cognitive performance, and simultaneously explore the influence of school vulnerability.

Methods: In this study, 1,196 Chilean adolescents participated (aged 10–14; 50.7% boys). Cardiorespiratory fitness (CRF), muscular fitness (MF), and speed-agility fitness (SAF) were evaluated, and a global fitness score (GFS) was computed adjusted for age and sex (CRF + MF + SAF z-scores). Body mass index z-score (BMIz), sum-of-4-skinfolds (4SKF), and waist-to-height ratio (WHtR) were used as non-specific, peripheral, and central adiposity indicators, respectively. A global cognitive score was computed based on eight tasks, and the school vulnerability index (SVI) was registered as high, mid or low. A total of 24 mediation analyses were performed according to two models, adjusted for sex and peak high velocity (Model 1), and adding the school vulnerability index (SVI) in Model 2. The significance level was set at p < 0.05.

Results: The fitness mediation role was different concerning the fatness indicators related to fat distribution analyzed. Even after controlling for SVI, CRF (22%), and SAF (29%), but not MF, mediated the association between BMIz and cognitive performance. Likewise, CRF, SAF and GFS, but not MF, mediated the association between WHtR and cognitive performance (38.6%, 31.9%, and 54.8%, respectively). No mediations were observed for 4SKF.

Conclusion: The negative association between fatness and cognitive performance is mitigated by the level of adolescents’ physical fitness, mainly CRF and SAF. This mediation role seems to be more consistent with a central fat indicator even in the presence of school vulnerability. Strategies promoting physical fitness would reduce the cognitive gap in children and adolescents related to obesity and school vulnerability.

Fitness Level Differences between Students in Kosovo and Montenegro

Geographical, cultural, and socio-economic factors create a different lifestyle. Accordingly, the aim of this research was to identify the differences in anthropometric and fitness characteristics among adolescents living in Montenegro and Kosovo in order to optimize the physical fitness as a consequence of the proactive behavior. Anthropometric characteristics and fitness level measures were assessed by Eurofit testing battery among 600 Kosovar and 600 Montenegrin students, equally distributed by gender. Differences between countries, gender, and age group (13, 14 and 15 years) were assessed with multivariate and univariate analysis of variance. The results showed that Montenegrin students are taller, heavier, and achieve better results in the sit-ups and 20-m endurance shuttle-run tests. Kosovar students achieve better results in the standing broad jump and 10 × 5 m shuttle-run tests. Males achieve significantly better results in all tests, excluding the sit-and-reach test. Statistically significant differences among age groups were found for all variables, regardless gender and country (except for the flamingo and sit-and reach tests). This study is of importance to physical education teachers and curriculum authors to optimize students’ proactive behavior based on the identified anthropometric and physical fitness differences between the two countries, age groups, and genders.

Socioeconomic status and physical fitness in youth: Findings from the NHANES National Youth Fitness Survey

This study examined the associations between socioeconomic status (SES) and musculoskeletal (MSF) and cardiorespiratory fitness (CRF) in youth.  The sample consisted of boys and girls between 3-15 years.  SES was categorized utilizing family-income-to-poverty ratio (FIPR).  All analyses were standardized for age and sex.  For each test of physical fitness, SES was used to estimate mean fitness test percentile and 95% confidence intervals, controlling for race/ethnicity and physical activity.  Odds ratios were calculated for the likelihood of having low fitness by SES category.  In general, the high SES group had a better composite MSF, body composition, and CRF profiles than low and moderate SES groups.  Statistically significant differences were identified for relative grip strength, plank, body mass index, and cardiovascular endurance time (all p < 0.05).  Additionally, the odds of low/poor MSF fitness were 1.7 and 1.6 times higher in the low and moderate SES groups (respectively) compared to the children from high SES families.  The moderate SES group had an odds of poor CRF 1.6 times higher than the high SES group as well.  Children and adolescents from high SES families tend to have higher mean fitness and were less likely to have low/poor fitness.

Association between Adherence to the Mediterranean Diet and Physical Fitness with Body Composition Parameters in 1717 European Adolescents: The AdolesHealth Study

Obesity, low levels of physical fitness, and unhealthy eating patterns are responsible for part of the health problems of adolescents today. The current study aimed at examining the association between the adherence to the Mediterranean diet (MD), through each answer to the items of the Adherence to the MD Questionnaire (KIDMED), and physical fitness with body composition parameters (body mass index (BMI), percentage of body fat, and waist circumference) in 1717 European adolescents (N = 900 boys, N = 817 girls). Data of body composition, physical fitness results, and the answers to KIDMED were analyzed by the Student’s t-test. Additionally, the effect size (ES) was calculated and a Chi-square test analyzed the proportion of participants with and without over waist circumference, overfat, and overweight in each KIDMED question. The relative risk of suffering over waist circumference, overfat and overweight in relation to the responses was calculated by Odd-Ratio. Adherence to the MD did not influence the condition of over waist circumference, overfat and overweight, although certain dietary habits were identified as risk factors for their development. Over waist circumference, overfat, and overweight boys and girls presented higher levels of body mass, waist circumference, body fat percentage, and BMI (p < 0.001; ES = 1.73–3.38), as well as lower levels of all the parameters of the physical fitness analyzed (p < 0.001; ES = 0.45–1.08), except the handgrip test. A direct relationship between fitness and over waist circumference, overfat, and overweight was found.

A cross-sectional study on the deprivation and sex differences in health-related fitness measures in school children

This study aimed to investigate deprivation and sex differences in selected health-relatedfitness measures in 9-12-year-old children. Data were captured on 3,407 children (49.3% boys; aged 10.5 ± 0.6 years). Cardiorespiratory fitness(20 m multistage shuttle run test; 20 m MSRT), muscular strength (handgrip strength) and body mass index (BMI) were measured. Welsh Index of Multiple Deprivation (WIMD) scores were used to make quintile groups. A two-way Analysis of Variance examined differences in BMI z-score by sex and WIMD quintiles. Two-wayAnalysis of Covariances investigated the effect of sex and WIMD quintiles on grip strength and shuttles achieved in 20 m MSRT, adjusting for BMI z-score and maturation, repectively. Independent of sex, children in the middle quintile had a significantly higher mean BMI z-score (p = 0.029) than their least deprived counterparts. There was a significant increase in grip strength (p = 0.005) and20 m MSRT (boys p < 0.001; girls p = 0.028) between most and least deprived quintiles. Significant differences in 20 m MSRT score were more apparent with decreases in deprivation in boys.Overall, inequalities exist in health-related fitness by sex and deprivation. These results can be used to inform focused services to improve current and future health.

Effect of Cardiorespiratory Fitness on Academic Achievement is Stronger in High-SES Elementary Schools Compared to Low

BACKGROUND

Academic achievement is influenced by factors at the student, school, and community levels. We estimated the effect of cardiorespiratory fitness performance on academic performance at the school level in Georgia elementary schools and examined effect modification by sociodemographic factors.

METHODS

This study is a repeat cross-sectional analysis of Georgia elementary schools between 2011 and 2014 (approximately 1138 schools per year). Multivariable beta regression estimated the effect of the proportion of 4th and 5th graders meeting cardiorespiratory fitness standards on the proportion of 5th graders passing standardized tests for Reading, English and Language Arts, Mathematics, Science, and Social Studies and considered potential interaction by school-level socioeconomic status (SES), racial composition, and urbanity.

RESULTS

There was a 0.15 higher estimated odds (OR: 1.15 (1.09, 1.22)) of passing the mathematics standardized test for every 10-percentage-point increase in school-level cardiorespiratory fitness among high-SES schools and 0.04 higher odds (OR: 1.04 (1.02, 1.05)) for low-SES schools. This pattern was similar for other academic subjects. No effect modification by racial composition or urbanity was observed for any academic subject.

CONCLUSIONS

Promoting physical fitness may be effective in improving academic performance among high-SES schools, but additional strategies may be needed among lower-SES schools.

30-year changes in Australian children's standing broad jump: 1985-2015

OBJECTIVES

Muscular strength is an important component of fitness that enables the execution of a range of daily activities across the lifespan including sport participation. The purpose of this study was to examine changes in children's standing broad jump, an indicator of muscular strength, between 1985 and 2015.

DESIGN

Two representative cross-sectional population surveys of Australian children age 9-15 years (n=7051).

METHODS

In 1985 and 2015 children's standing broad jump (SBJ; cm) and anthropometry were measured by trained field teams. General linear regression examined the temporal change in SBJ by sex and age adjusting for height, weight, socioeconomic status, and linguistic background.

RESULTS

Over a 30-year period, the height, weight, and BMI of children significantly increased and muscular strength decreased. Among boys, the adjusted SBJ distance declined -4.5cms (95%CI -8.8, -0.10) in 9-11 year olds and 7.6cms (95%CI -12.5, -2.7) in 12-15 year olds. Among girls, the adjusted SBJ distance declined 8.5cms (95%CI -12.9, -4.2) in 9-11 year olds and 9.3cms (95%CI -14.1, -4.6) in 12-15 year olds. Larger declines in the distance jumped were observed among children and adolescents from non-English speaking backgrounds, than English speaking peers and children from low socioeconomic neighbourhoods than the declines among children from high SES neighbourhoods.

CONCLUSIONS

Overall, the distance children and adolescents jumped in 2015 was lower than the distance their peers jumped in 1985. The declines differed by sex and sociodemographic characteristics, which suggests targeted sub-population interventions to improve children's muscular strength should be considered.

The Daily Mile makes primary school children more active, less sedentary and improves their fitness and body composition: a quasi-experimental pilot study

BACKGROUND

The Daily Mile is a physical activity programme made popular by a school in Stirling, Scotland. It is promoted by the Scottish Government and is growing in popularity nationally and internationally. The aim is that each day, during class time, pupils run or walk outside for 15 min (~1 mile) at a self-selected pace. It is anecdotally reported to have a number of physiological benefits including increased physical activity, reduced sedentary behaviour, increased fitness and improved body composition. This study aimed to investigate these reports.

METHODS

We conducted a quasi-experimental repeated measures pilot study in two primary schools in the Stirling Council area: one school with, and one without, intention to introduce the Daily Mile. Pupils at the control school followed their usual curriculum. Of the 504 children attending the schools, 391 children in primary classes 1-7 (age 4-12 years) at the baseline assessment took part. The follow-up assessment was in the same academic year. Outcomes were accelerometer-assessed average daily moderate to vigorous intensity physical activity (MVPA) and average daily sedentary behaviour, 20-m shuttle run fitness test performance and adiposity assessed by the sum of skinfolds at four sites. Valid data at both time points were collected for 118, 118, 357 and 327 children, respectively, for each outcome.

RESULTS

After correction for age and gender, significant improvements were observed in the intervention school relative to the control school for MVPA, sedentary time, fitness and body composition. For MVPA, a relative increase of 9.1 min per day (95% confidence interval or 95%CI 5.1-13.2 min, standardised mean difference SMD = 0.407, p = 0.027) was observed. For sedentary time, there was a relative decrease of 18.2 min per day (10.7-25.7 min, SMD = 0.437, p = 0.017). For the shuttle run, there was a relative increase of 39.1 m (21.9-56.3, SMD = 0.236, p = 0.037). For the skinfolds, there was a relative decrease of 1.4 mm (0.8-2.0 mm, SMD = 0.246, p = 0.036). Similar results were obtained when a correction for socioeconomic groupings was included.

CONCLUSIONS

The findings show that in primary school children, the Daily Mile intervention is effective at increasing levels of MVPA, reducing sedentary time, increasing physical fitness and improving body composition. These findings have relevance for teachers, policymakers, public health practitioners, and health researchers.

Socio-demographic differences in Colombian children's muscular fitness: Does scaling for differences in body size present a challenge to conventional thinking?

OBJECTIVES

In low- to middle-income countries, children from less-deprived areas (from families of higher socio-economic status [SES]) have superior muscular fitness than those from low-SES groups. They are also taller and heavier, factors associated with muscular fitness. The purpose of this study was to identify any socio-demographic differences in Colombian children's muscular fitness and examine how these conclusions can be modified by scaling for differences in body size.

METHODS

A total of 38,098 youths (46% girls), ninth grade students (aged 14-15 years), participated in a study of cross-sectional design. We recorded SES and family incomes, stature, and mass. Standing broad jump and handgrip strength were used to assess muscular fitness. A multiplicative allometric model was adopted to adjust for body-size differences.

RESULTS

Children from the mid- to high-SES groups jumped significantly higher than children from the lowest SES group, although no SES group difference in grip strength was observed. After adjusting for body size, children from higher SES and with higher family incomes had significantly lower handgrip strength, and their superior jump height performances remained but were greatly reduced. Only children from the highest SES now jumped significantly higher that the lowest SES group.

CONCLUSIONS

The superior jump performance and no difference in handgrip strength of Colombian children from higher SES may simply reflect their superior physiques. When body size is accounted for, these differences are reduced or even reversed, suggesting that children from higher SES groups should not be complacent regarding their apparent superior muscular fitness.

Handgrip strength values of Portuguese older adults: a population based study

Background

Handgrip strength is used to identify sarcopenia and frailty phenotypes, being a potential predictor of mortality in older adults. However, uniformity is lacking in the reference values. This study aimed to describe handgrip strength values of older population aged ≥65 years in Portugal, considering the possible influence of anthropometric parameters.

Methods

A cross-sectional study was conducted in Portugal, among 1500 older adults aged ≥65 years old, according to “The Nutrition UP 65 Study Protocol”. Demographic data were collected and cognitive performance, subjective general health, physical activity, anthropometric parameters and nutritional status were assessed and analysed. Handgrip strength data was obtained with a Jamar dynamometer. A Pubmed/Medline search was carried out to compare handgrip strength data between Portuguese older adults and other older populations.

Results

Handgrip strength was higher among men than among women (30.3 ± 9.2 Kgf vs 18 ± 5.4 Kgf, p < 0.001, respectively). In general, handgrip strength values of Portuguese older adults were lower than other older populations. In our sample, age, cognitive and nutritional status, self-reported sitting time and practice of physical activity were significantly correlated with handgrip strength in both sexes. Concerning anthropometric parameters, height was the most significantly correlated with handgrip strength (r = 0.34, p < 0.001, in women and r = 0.40, p < 0.001, in men).

Conclusion

This study described, for the first time, handgrip strength values of Portuguese population aged ≥65 years, according to age and to sex-specific tertiles of height. The definition of handgrip strength reference values in this age group merits further reflection.

The Relationship between Socioeconomic Status, Family Income, and Measures of Muscular and Cardiorespiratory Fitness in Colombian Schoolchildren

OBJECTIVE

To determine the associations between socioeconomic status (SES) and physical fitness in a sample of Colombian youth.

STUDY DESIGN

Prueba SER is cross-sectional survey of schoolchildren in Bogota, Colombia. Mass, stature, muscular fitness (standing long-jump, handgrip), and cardiorespiratory fitness (20-m shuttle run) were measured in 52?187 schoolchildren 14-16 years of age. Area-level SES was categorized from 1 (very low) to 4 (high) and parent-reported family income was categorized as low, middle, or high.

RESULTS

Converting measures into z scores showed stature, muscular, and cardiorespiratory fitness were significantly (z?=?0.3-0.7) below European values. Children in the mid- and high SES groups jumped significantly further than groups with very low SES. Differences were independent of sex but became nonsignificant when adjusted for anthropometric differences. Participants in the mid-SES and high-SES groups had better handgrip scores when adjusted for body dimension. There were, however, no significant between-group differences in cardiorespiratory fitness, which was strongly clustered by school and significantly greater in students from private schools.

CONCLUSIONS

Area-level SES is associated with measures of muscular fitness in Colombian schoolchildren. These associations were largely explained by the large differences in body dimensions observed between SES groups. When area-level SES is considered, there was no evidence that family income influenced fitness. The clustering of outcomes reaffirms the potential importance of schools and area-level factors in promoting fitness through opportunities for physical activity. Interventions implemented in schools, can improve academic attainment; a factor likely to be important in promoting the social mobility of children from poorer families.

Socioeconomic indicators, obesity, and physical fitness in south Brazilian adolescents with Down syndrome

Objectives: The aim was to examine the association of potential socioeconomic indicators with obesity and physical fitness components in south Brazilian adolescents with Down syndrome. Methods: This study comprised a total of 1249 (669 boys) adolescents with Down syndrome aged 10 to 20 with complete baseline data. Socioeconomic indicators were assessed by a proxy-report questionnaire. Body mass index and physical fitness were assessed using a PROES-BR health-related fitness test battery. Results: Socioeconomic status is not associated with body mass index in adolescents with Down syndrome. In addition, two of five physical fitness variables were associated with groups of family income and paternal education level in boys, while one of five physical fitness variables were associated with groups of paternal and maternal education level in girls. Conclusion: Our results suggest that socioeconomic indicators are associated with some components of physical fitness in Brazilian adolescents with Down syndrome. These associations depend on the socioeconomic status and physical fitness components in boys and girls.

Reference ranges of handgrip strength from 125,462 healthy adults in 21 countries: a prospective urban rural epidemiologic (PURE) study

BACKGROUND

The measurement of handgrip strength (HGS) has prognostic value with respect to all-cause mortality, cardiovascular mortality and cardiovascular disease, and is an important part of the evaluation of frailty. Published reference ranges for HGS are mostly derived from Caucasian populations in high-income countries. There is a paucity of information on normative HGS values in non-Caucasian populations from low- or middle-income countries. The objective of this study was to develop reference HGS ranges for healthy adults from a broad range of ethnicities and socioeconomically diverse geographic regions.

METHODS

HGS was measured using a Jamar dynamometer in 125,462 healthy adults aged 35-70 years from 21 countries in the Prospective Urban Rural Epidemiology (PURE) study.

RESULTS

HGS values differed among individuals from different geographic regions. HGS values were highest among those from Europe/North America, lowest among those from South Asia, South East Asia and Africa, and intermediate among those from China, South America, and the Middle East. Reference ranges stratified by geographic region, age, and sex are presented. These ranges varied from a median (25^th-75^th percentile) 50 kg (43-56 kg) in men <40 years from Europe/North America to 18 kg (14-20 kg) in women >60 years from South East Asia. Reference ranges by ethnicity and body-mass index are also reported.

CONCLUSIONS

Individual HGS measurements should be interpreted using region/ethnic-specific reference ranges.

A non-equivalent group pilot trial of a school-based physical activity and fitness intervention for 10-11 year old english children: born to move

Background

PE lessons are the formal opportunity in schools for promotion of physical activity and fitness. This study aimed to evaluate the effectiveness of a pilot PE intervention on physical activity, fitness, and psychosocial outcomes.

Methods

Participants were 139 children aged 10–11 years from four schools. For six weeks children in two schools received a twice-weekly pilot ‘Born to Move’ (BTM) physical activity (PA) and fitness intervention alongside one regular PE lesson. Children in the two comparison (COM) schools received their regular twice weekly PE lessons. Outcomes were lesson time and whole-day light (LPA), moderate (MPA), vigorous (VPA), and MVPA, and sedentary time, muscular fitness, cardiorespiratory fitness (CRF), and lesson-specific perceived exertion, enjoyment, and perceived competence. Outcomes were assessed at baseline (T0), midway through the intervention (T1), and at the end (T2) using ANOVAs and ANCOVAs. Intervention fidelity was measured using child and teacher surveys at T2 and analysed using Chi-square tests.

Results

The BTM group engaged in moderate PA for significantly more lesson time (29.4 %) than the COM group (25.8 %; p = .009, d = .53). The amount of moderate-to-vigorous PA (MVPA) during the T1 BTM lesson contributed 14.0 % to total MVPA, which was significantly more than the COM group’s T1 PE lesson (11.4 %; p < .001, d = .47). The BTM group were significantly more active during the whole-day (p < .05) and the school-day (p < .01). In both groups push-up test performance increased (p < .001) and CRF test performance decreased (p < .01). Perceived exertion, enjoyment, and perceived competence increased in both groups (p < .05), but the BTM group rated their enjoyment of the T1 BTM lesson higher than the COM group rated their PE lesson (p = .02, d = .56). The children’s and teachers’ responses to the intervention indicated that the delivery aims of enjoyment, engagement, inclusivity, and challenge were satisfied.

Conclusions

The BTM pilot programme has potential to positively impact on physical activity, fitness, and psychosocial outcomes. Further, BTM was enjoyed by the children, and valued by the teachers. This study can inform the design of a modified larger-scale cluster RCT evaluation.

Effect of a Trampoline Exercise on the Anthropometric Measures and Motor Performance of Adolescent Students

Background:

Physical exercises can influence some anthropometric and fitness components differently. The aim of present study was to evaluate how a relatively long-term training program in 11-14-year-old male Iranian students affects their anthropometric and motor performance measures.

Methods:

Measurements were conducted on the anthropometric and fitness components of participants (n = 28) prior to and following the program. They trained 20 weeks, 1.5 h/session with 10 min rest, in 4 times trampoline training programs per week. Motor performance of all participants was assessed using standing long jump and vertical jump based on Eurofit Test Battery.

Results:

The analysis of variance (ANOVA) repeated measurement test showed a statistically significant main effect of time in calf girth P = 0.001, fat% P = 0.01, vertical jump P = 0.001, and long jump P = 0.001. The ANOVA repeated measurement test revealed a statistically significant main effect of group in fat% P = 0.001. Post hoc paired t-tests indicated statistical significant differences in trampoline group between the two measurements about calf girth (t = −4.35, P = 0.001), fat% (t = 5.87, P = 0.001), vertical jump (t = −5.53, P = 0.001), and long jump (t = −10.00, P = 0.001).

Conclusions:

We can conclude that 20-week trampoline training with four physical activity sessions/week in 11–14-year-old students seems to have a significant effect on body fat% reduction and effective results in terms of anaerobic physical fitness. Therefore, it is suggested that different training model approach such as trampoline exercises can help students to promote the level of health and motor performance.

IQ and obesity in adolescence: a population-based, cross-sectional study

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT

Low IQ is associated with high BMI in childhood. There are inconsistent findings on the association between low SES and high BMI. Youth with low IQ have been reported to have poorer health behaviors, such as poor nutrition and less physical activity.

WHAT THIS STUDY ADDS

Low IQ is significantly associated with obesity for both male and female adolescents, though more strongly for female adolescents. Physical activity has a mediating effect on the association between low IQ and obesity among both male and female adolescents, though more strongly for male adolescents. The association between low IQ and obesity is strongest among adolescents from high SES backgrounds.

BACKGROUND

Previous studies have shown an association between low intelligence quotient (IQ), high body mass index and low socioeconomic status (SES).

OBJECTIVES

This study examined the cross-sectional association between IQ and obesity, exploring the roles of gender, SES and physical activity in this association.

METHODS

Subjects were 235,663 male and 169,259 female adolescents assessed by the Israeli military draft board.

RESULTS

Low IQ was significantly associated with increased odds of obesity among male (odds ratio [OR] = 1.44, 95% confidence interval [CI] = 1.36-1.52) and female adolescents (OR = 1.61, 95% CI = 1.51-1.73); this association was significantly stronger among female adolescents. Sobel tests indicated that physical activity had a significant mediating effect on this association for male and female adolescents, although more strongly for male adolescents. Dividing the sample according to SES, the association between low IQ and obesity was strongest in the high SES group (male adolescents: OR = 1.26, 95% CI = 1.10-1.43, female adolescents: OR = 1.61, 95% CI = 1.38-1.89), even when controlling for physical activity.

CONCLUSIONS

The findings suggest that low IQ is associated with increased odds of obesity, particularly in female adolescents and in adolescents with high SES. Physical activity has a mediating effect on this association, although more strongly for male than for female adolescents. Public health measures on decreasing obesity might focus on these groups.

Geographical variation in health-related physical fitness and body composition among Chilean 8th graders: a nationally representative cross-sectional study

PURPOSE

In addition to excess adiposity, low cardiorespiratory fitness (CRF) and low musculoskeletal fitness (MSF) are important independent risk factors for future cardio-metabolic disease in adolescents, yet global fitness surveillance in adolescents is poor. The objective of this study was to describe and investigate geographical variation in levels of health-related physical fitness, including CRF, MSF, body mass index (BMI), and waist circumference (WC) in Chilean 8th graders.

METHODS

This cross-sectional study was based on a population-based, representative sample of 19,929 8th graders (median age = 14 years) in the 2011 National Physical Education Survey from Chile. CRF was assessed with the 20-meter shuttle run test, MSF with standing broad jump, and body composition with BMI and WC. Data were classified according to health-related standards. Prevalence of levels of health-related physical fitness was mapped for each of the four variables, and geographical variation was explored at the country level by region and in the Santiago Metropolitan Area by municipality.

RESULTS

Girls had significantly higher prevalence of unhealthy CRF, MSF, and BMI than boys (p<0.05). Overall, 26% of boys and 55% of girls had unhealthy CRF, 29% of boys and 35% of girls had unhealthy MSF, 29% of boys and 44% of girls had unhealthy BMI, and 31% of adolescents had unhealthy WC. High prevalence of unhealthy fitness levels concentrates in the northern and middle regions of the country and in the North and Southwest sectors for the Santiago Metropolitan Area.

CONCLUSION

Prevalence of unhealthy CRF, MSF, and BMI is relatively high among Chilean 8th graders, especially in girls, when compared with global estimates. Identification of geographical regions and municipalities with high prevalence of unhealthy physical fitness presents opportunity for targeted intervention.

Associations between objectively assessed child and parental physical activity: a cross-sectional study of families with 5-6 year old children

Background

A number of studies have suggested that there is a need to increase the physical activity levels of children. Parents are important influences on children’s behaviour. There is a lack of information about whether there are associations between the physical activity levels of young children and their parents. The current study examined the associations between the physical activity (PA) of parents and their children at age five to six years old, and determined whether any associations differed by child or parent gender or between week and weekend days.

Methods

Cross-sectional study, with 1267 Year 1 pupils (five to six years of age) and at least one parent from 57 primary schools. Children and parents wore an accelerometer for five days and mean minutes of moderate-to-vigorous intensity physical activity (MVPA) per day were derived. We used multivariable linear regression to investigate whether parental and child time spent in MVPA was associated with each other. Each model was adjusted for age, child gender, parent BMI and neighbourhood deprivation with subgroup analysis by child gender.

Results

80% of parents met PA guidelines, however 29% of boys and 47% of girls aged five to six years failed to meet them. Fully-adjusted analyses suggested weak positive associations of parent’s and children’s time spent in MVPA. Every 10 additional minutes of parental MVPA were associated with one additional minute of child MVPA. There was no evidence of a difference in associations for boys and girls or between mothers and fathers.

Conclusions

29% of boys and 47% of girls aged five to six years did not meet PA guidelines indicating that these children would benefit from new approaches that focus on increasing physical activity. There were weak associations between the MVPA of 5–6 year old children and their parents, demonstrating that the time that children are active with their parents is not a major source of physical activity. Clinicians and public health professionals should encourage parents to create opportunities for their children to be active.

Effect of living area and sports club participation on physical fitness in children: a 4 year longitudinal study

Background

Cross-sectional studies detected associations between physical fitness, living area, and sports participation in children. Yet, their scientific value is limited because the identification of cause-and-effect relationships is not possible. In a longitudinal approach, we examined the effects of living area and sports club participation on physical fitness development in primary school children from classes 3 to 6.

Methods

One-hundred and seventy-two children (age: 9–12 years; sex: 69 girls, 103 boys) were tested for their physical fitness (i.e., endurance [9-min run], speed [50-m sprint], lower- [triple hop] and upper-extremity muscle strength [1-kg ball push], flexibility [stand-and-reach], and coordination [star coordination run]). Living area (i.e., urban or rural) and sports club participation were assessed using parent questionnaire.

Results

Over the 4 year study period, urban compared to rural children showed significantly better performance development for upper- (p = 0.009, ES = 0.16) and lower-extremity strength (p < 0.001, ES = 0.22). Further, significantly better performance development were found for endurance (p = 0.08, ES = 0.19) and lower-extremity strength (p = 0.024, ES = 0.23) for children continuously participating in sports clubs compared to their non-participating peers.

Conclusions

Our findings suggest that sport club programs with appealing arrangements appear to represent a good means to promote physical fitness in children living in rural areas.

Role of socio-cultural factors on changes in fitness and adiposity in youth: a 6-year follow-up study

BACKGROUND AND AIMS

Optimal cardio-respiratory fitness and adiposity levels are tightly related to health in youth. We analysed changes in fitness and adiposity in young individuals from two countries, and examined the role of maternal education in these changes.

METHODS AND RESULTS

A 6-year follow-up study was conducted on 483 Estonian children (9 years) and 466 Swedish children (9-10 years) and adolescents (15 years). Fitness was assessed by a maximal bike test, and total and central adiposity were indirectly estimated by skinfolds (Slaughter's equation for fat mass) and waist circumference. At follow-up, fitness and adiposity had increased in the children cohort (P ≤ 0.001), while small or no change occurred in the adolescent cohort. In the children cohort, Estonian participants had a lower increase in fitness and a higher increase in adiposity (total and central) than Swedish participants. Higher maternal education increased the odds of remaining fit (top quartile) by half and reduced the risk of remaining fat (top quartile) by half; odds ratios = 1.56 (1.00-2.43), 0.50 (0.32-0.77) and 0.61 (0.39-0.94) for fitness, total and central adiposity, respectively.

CONCLUSIONS

Our data suggest that the socioeconomic situation of a country might influence key cardiovascular risk factors (fitness and adiposity), being at higher risk for a low-middle income country (Estonia) than a higher income country (Sweden). The findings stress the role of socioeconomic status, particularly maternal education, in the maintenance of healthy fitness and adiposity levels from childhood into later life. Preventive efforts have to be taken from early age.

BMI may underestimate the socioeconomic gradient in true obesity

BACKGROUND

Body mass index (BMI) does not make a distinction between fat mass and lean mass. In children, high fat mass appears to be associated with low maternal education, as well as low lean mass because maternal education is associated with physical activity. Therefore, BMI might underestimate true obesity in children of low-educated mothers.

OBJECTIVE

To investigate the associations of maternal education with fat mass index (FMI), lean mass index (LMI) and BMI.

METHODS

In total, 1965 Dutch children from a prospective cohort, aged 5.7 years (standard deviation 0.5), had available data on body composition based on bioelectrical impedance analysis.

RESULTS

Maternal education was not associated with BMI after adjustment for confounders. In contrast, children of low-educated mothers had a higher FMI (β 0.28 95% confidence interval [CI] 0.07; 0.49) and a lower LMI (β -0.18 95% CI -0.33; -0.03) compared with children of high-educated mothers.

CONCLUSIONS

This suggests that BMI underestimates the educational gradient of childhood obesity.

Socioeconomic and other social stressors and biomarkers of cardiometabolic risk in youth: a systematic review of less studied risk factors

Background

Socioeconomic disadvantage and other social stressors in childhood have been linked with cardiometabolic diseases in adulthood; however the mechanisms underlying these observed associations and the timing of their emergence are unclear. The aim of this review was to evaluate research that examined relationships between socioeconomic disadvantage and other social stressors in relation to less-studied cardiometabolic risk factors among youth, including carbohydrate metabolism-related factors, lipids, and central adiposity.

Methods

We searched PubMed and ISI Web of Science to identify relevant publications between 2001 and 2013.Studies were selected based on 4 criteria: (1) the study examined an association between at least one social or economic stressor and one relevant outcome prior to age 21; (2) the sample originated from a high-income country; (3) the sample was not selected based on a health condition; and (4) a central aim was to evaluate the effect of the social or economic stressor on at least one relevant outcome. Abstracts were screened and relevant publications were obtained and evaluated for inclusion criteria. We abstracted data from selected articles, summarized them by exposures and outcomes, and assigned an evidence grade.

Results

Our search identified 37 publications from 31 studies. Socioeconomic disadvantage was consistently associated with greater central adiposity. Research to date does not provide clear evidence of an association between childhood stressors and lipids or carbohydrate metabolism-related factors.

Conclusions

This review demonstrates a paucity of research on the relationship of socioeconomic disadvantage and other social stressors to lipid and carbohydrate metabolism-related factors in youth. Accordingly, it is not possible to form strong conclusions, particularly with regard to stressors other than socioeconomic disadvantage. Findings are used to inform priorities for future research. An improved understanding of these pathways is critical for identifying novel prevention targets and intervention opportunities to protect the long-term health of children and adolescents.

Cardiorespiratory fitness, activity level, health-related anthropometric variables, sedentary behaviour and socioeconomic status in a sample of Iranian 7-11 year old boys

The purpose of this study was to evaluate cardiorespiratory fitness (CRF), activity level, some health-related anthropometric variables, sedentary behaviour and socioeconomic status (SES) of 7-11 year old boys in the city of Ardabil, Iran. Of 21 253 school boys aged 7-11 years, 766 participated in this study using the cluster sampling method. Subjects underwent standard anthropometry. One-mile test was used to evaluate V.O₂ max. BMI cut-off points were used to identify weight status. Child's TV watching and video playing daily time (TVVPT) was taken for sedentary behaviour evaluation. SES and activity level were measured by standard questionnaires. Of all participants, 8.9% (N=68) of students had CRF lower than normal and 58.6% (N=449) of them had inadequate physical activity. There was a significant adverse relationship between V.O₂ max and body mass index (BMI), waist to height ratio (WHtR), waist circumference (WC), and fat mass (FM) (p<0.05). A significant direct association between SES and both FM and TVVPT was observed (p<0.05). Significantly lower physical activity and V.O₂ max, and higher TVVPT were observed in the obese boys than their counterparts (p<0.05). The results of this study indicated a significant relationship between CRF and physical activity, and health-related anthropometric variables in a selected sample of 7-11 year boys. Moreover, the obese subjects had not only lower physical activity but also longer sedentary behaviour time than their counterparts.

Associations of parental education and parental physical activity (PA) with children's PA: the ENERGY cross-sectional study

OBJECTIVE

The present study sought to examine the independent associations of parental education and physical activity (PA) with children's PA across Europe.

METHODS

A total of 7214 children (10-12 years) were recruited from a school-based cross-sectional survey during 2010 in seven European countries. Weight and height were measured. Parental educational level (PEL) and parents' and children's PA were collected using self-reported questionnaires. Multiple linear regression models were used, comparing children's PA with PEL and PA levels.

RESULTS

PEL was directly associated with children's PA in Greek and Spanish girls (all P<0.01) and boys' PA in Norway (all P<0.05). Paternal education was directly associated with PA in Hungarian boys (P<0.05). In overall, parental PA was directly associated with children's PA in more than half of the countries involved (all P<0.05).

CONCLUSIONS

Our observations suggest that PEL and parental modeling of PA are two independent factors from the home environment influencing the children's PA, but the relationships were gender- and country-specific. Further studies should be focused on intervention strategies for increasing children's PA but considering the important role of these two aspects and especially on the modification of parental modeling of PA.

Changes in cardiorespiratory fitness in 9- to 10.9-year-old children: SportsLinx 1998-2010

PURPOSE

The study's purposes were to 1) assess changes in cardiorespiratory fitness (CRF) from 1998 to 2010, controlling for decimal age and body mass index (BMI), and 2) repeat the analysis in cohorts from 2005 to 2010, controlling for maturation, deprivation, and BMI.

METHODS

A total of 27,942 (n = 14,247 boys) 9- to 10.9-yr-old participants from one UK city were included in this serial cross-sectional study from 1998-1999 to 2009-2010. An indices of multiple deprivation (IMD) score was assigned to each participant on the basis of home postcode. Stature, sitting stature, and body mass were estimated. BMI and somatic maturity were calculated. Performance on the 20-m multistage shuttle run test (20mSRT) was used to estimate CRF (total shuttles). One-way ANCOVAs were completed to assess temporal trends in CRF, separately by sex. Model 1 assessed changes from 1998 to 2010 and included decimal age and BMI as covariates. Model 2 assessed changes from 2005 to 2010 and included maturity, IMD, and BMI as covariates.

RESULTS

Results indicate that 20mSRT performance has declined in UK schoolchildren. An annual decline of 1.34% and 2.29% was observed in boys and girls, respectively. In model 1, for boys, the baseline cohort performed better than all other groups with the exception of the 1999-2000 group. For girls, declines in 20mSRT performance were observed from 2003 onward. In model 2, for boys, the 2007-2008 and 2008-2009 cohorts completed fewer 20mSRT shuttles than all other groups. For girls, the 2007-2008 and 2008-2009 cohorts also performed worse than all other years.

CONCLUSIONS

The decline in CRF suggests children in the more recent SportsLinx cohorts may be at an increased risk of cardiometabolic illness in comparison with earlier cohorts. The promotion of vigorous physical activity is urged to promote CRF in children.

Socioeconomic status and bone mass in Spanish adolescents. The HELENA Study

PURPOSE

Socioeconomic status (SES) has been frequently associated with body composition, particularly fat mass and obesity. However, the SES-bone mass association is not clear. We aimed to evaluate the associations between different SES indicators (Family Affluence Scale, parental education, and occupation) and bone mineral content in Spanish adolescents.

METHODS

Participants were 322 adolescents (164 boys and 158 girls, 12.5-17.5 years) from the Healthy Lifestyle in Europe by Nutrition in Adolescence study. The social background of the adolescents was self-reported using an SES questionnaire, and the bone variables were measured using dual-energy x-ray absorptiometry. Physical activity was measured using accelerometers. Calcium intake was estimated from two nonconsecutive 24 hours recalls. One-way analysis of covariance was performed to examine the relationships between SES indicators and bone mass using different sets of confounders: basic model (sex + sexual maturation), model 1 (basic model + height), model 2 (basic model + lean mass), and model 3 (basic model + calcium intake + average physical activity).

RESULTS

Adjusted results showed no association between SES indicators and whole-body or total hip bone mineral content. Additional analyses were performed in lumbar spine, pelvis, and hip subregions (femoral neck, trochanter, and intertrochanter), and no significant associations were observed at these sites either.

CONCLUSIONS

Our data do not support a link between different SES indicators (Family Affluence Scale, parental education, and occupation) and bone mass in adolescents.

Exclusive breastfeeding duration and cardiorespiratory fitness in children and adolescents

BACKGROUND

Breastfeeding has been associated with a protective effect against cardiovascular disease. Higher cardiorespiratory fitness during childhood is associated with healthier cardiovascular profile later in life.

OBJECTIVES

The objective was to examine the association of exclusive breastfeeding duration with fitness in children and adolescents and to test the role of body composition and sociodemographic factors in this relation.

DESIGN

At the time of the study, exclusive breastfeeding duration was reported by mothers and grouped into 4 categories: exclusively formula fed or breastfed for <3, 3-6, or >6 mo. Fitness was determined by a maximal cycle-ergometer test in 1025 children (aged 9.5 ± 0.4 y) and in 971 adolescents (aged 15.5 ± 0.5 y) from Estonia and Sweden.

RESULTS

Longer duration of breastfeeding was associated with higher fitness regardless of confounders [+5.1% L/min; country, sex, age, pubertal status, and BMI (adjusted P < 0.001) or fat mass and fat-free mass (FFM) (+3.3%; adjusted P < 0.001)]. Further adjustment for birth weight, physical activity, and maternal educational level did not change the results (P = 0.001). The results were consistent in children and adolescents with low (P < 0.001) or high (P = 0.013) FFM, in nonoverweight (P < 0.001) or overweight (P = 0.002) children and adolescents, in offspring of nonoverweight (P < 0.001) or overweight (P = 0.003) mothers, in mothers with a low (P = 0.004) or high (P < 0.001) educational level, and in participants born within upper (P = 0.001), middle (P = 0.017), or lower (P = 0.007) tertiles of birth weight.

CONCLUSIONS

Longer exclusive breastfeeding has a beneficial effect on cardiorespiratory fitness in children and adolescents. Because early infant-feeding patterns are potentially modifiable, a better understanding of the possible programming effect of exclusive breastfeeding on cardiorespiratory fitness is of public health interest.

Correlates of aerobic fitness in urban and rural Portuguese adolescents

BACKGROUND

Improving physical fitness is often an objective of programmes aimed at preventing obesity among youth.

AIM

To evaluate the association between cardiorespiratory fitness (CRF) and area of residence controlling for several correlates in adolescents.

SUBJECTS AND METHODS

CRF was assessed with the progressive aerobic cardiovascular endurance run (PACER) test in a cross-sectional sample of 362 Portuguese adolescents (165 males, 197 females) of 13-16 years of age. Youth were classified by area of residence as urban or rural. Gender, age, weight status, parental education, screen time (inactivity) and moderate-to-vigorous physical activity (MVPA) were statistically controlled. Logistic regression analysis was used.

RESULTS

Adolescents of both sexes from rural settings were 76% more likely to be classified as aerobically fit compared to those from urban areas. The odds ratio for CRF in the final model was similar in boys (OR = 0.24, 95% CI 0.06-0.99, p < 0.05) and girls (OR = 0.24, 95% CI 0.07-0.76, p < 0.05). MVPA and weight status were important predictors of CRF in Portuguese adolescents of 13-16 years of age. Maternal education was an additional predictor in girls.

CONCLUSION

CRF and rural/urban settings were significantly related in this sample of Portuguese adolescents of both sexes.