Obesity and Aerobic Fitness among Urban Public School Students in Elementary, Middle, and High School

Assessment of physical activity among adolescents: a guide to the literature

Purpose

The aim of this article is to systematically review articles and annual reports concerning young peoples' physical activity (PA) and linking this to considerations of the state and national defense.

Method

A systematic search of the literature included an analysis of publications accessible in global databases and other available books, student papers, and projects. The articles and reports were categorized based on year of publication, methods used, age of respondents, sample size, country, and digital object identifier (DOI).

Results

The result of this search is an overview of the extent and manner in which the worldwide scientific community is addressing the current situation and the long-term development of the physical fitness of adolescents. This publication also maps to what extent professional publications and articles are addressing PA from the perspective of the needs of armies and armed forces of various countries around the world.

Conclusions

The article provides a systematic overview of methods used to measure PA, and an overview of articles dealing with assessing PA. The examined articles indicate that from the perspective of not only national defense, but also health and overall quality of life, in particular, we need initiatives to encourage and motivate young people to increase their everyday PA. The research therefore also includes an overview of factors that may considerably influence PA. The results ascertained in this publication will be used, i.a. for investigating a longitudinal defense research project of the Ministry of Defense of the Czech Republic in which the authors are participating.

Severe obesity and fitness in New York City public school youth, 2010-2018

BACKGROUND

Obesity is associated with poorer youth fitness. However, little research has examined the magnitude of this relationship in youth with severe obesity. Therefore, we sought to determine the relationship between increasing weight status and fitness within a sample of children and adolescents from New York City public schools.

METHODS

This study utilized longitudinal data from the NYC Fitnessgram dataset years 2010-2018. Height and weight along with fitness were measured annually during physical education classes. Severity of obesity was defined using body mass index relative to the 95th percentile and then categorized into classes. A composite measure of fitness was calculated based on scores for three fitness tests: aerobic capacity, muscular strength, and muscular endurance. To examine the weight status-fitness relationship, repeated measures mixed models with random-intercepts were constructed. Stratified models examined differences by demographic factors.

RESULTS

The sample included 917,554 youth (51.8% male, 39.3% Hispanic, 29.9% non-Hispanic Black, 14.0%, 4.6%, and 1.6% class I, II and III obesity, respectively). Compared to youth with healthy weight, increasing severity of obesity was associated with decreased fitness: overweight (β = - 0.28, 95% CI:-0.29;-0.28), class I obesity (β = - 0.60, 95% CI:-0.60; - 0.60), class II obesity (β = - 0.94, 95% CI:-0.94; - 0.93), and class III obesity (β = - 1.28; 95% CI:-1.28; - 1.27). Stratified models showed the association was stronger among male and non-Hispanic White youth.

CONCLUSION

Findings revealed that more severe obesity was associated with lower fitness. Future research is needed to develop targeted interventions to improve fitness in youth with obesity.

The Impact of Obesity on the Fitness Performance of School-Aged Children Living in Rural Areas-The West Attica Project

This study aimed to investigate the relationship of body mass index (BMI) with muscle and cardiorespiratory fitness in children living within rural areas (regional unit of West Attica) in Greece. Participants included 399 students (187 boys, 212 girls), ages 8-12 years old, and were evaluated in physical performance tests. The point prevalence of overweight and obesity was 21.39% and 26.20% in boys, and 19.90% and 23.79% in girls. Significant differences were observed in all physical performance tests (handgrip, long jump, shuttle run, trunk flexors, and extensors endurance) between normal weight and obese participants. BMI was positively correlated with handgrip (r = 0.442-0.462, p < 0.001). There was a negative association with long jump (r = -0.206, p < 0.001), 20 m shuttle run (r = -0.394, p < 0.001), trunk flexors (r = -0.403, p < 0.001) and trunk extensors endurance (r = -0.280, p < 0.001). The regression analysis showed that 20-30% of the overall variation for physical performance assessments could be accounted for by BMI, age, and sex. With the exception of the long jump and the endurance of the trunk extensors, BMI alone may explain more than 10% of the outcome of most tests. This study highlights the determinant of BMI on muscle and cardiorespiratory fitness. The management of obesity should begin early in childhood to prevent adult chronic cardiovascular and metabolic diseases.

Longitudinal Association between Weight Status, Aerobic Capacity, Muscular Strength, and Endurance among New York City Youth, 2010-2017

Background: Child weight status is inversely associated with fitness, but less is known about this relationship across fitness domains. This study examined the longitudinal association between weight status and fitness domains in a large, diverse sample of children. Methods: Data were drawn from the New York City Fitnessgram (2010-2011 to 2017-2018). Height and weight were collected annually and converted to weight status using Centers for Disease Control and Prevention growth charts. Aerobic capacity, muscular strength, and endurance were measured as age and sex standardized z-scores based on the fitness performance tests. Repeated-measures multilevel models were run testing the association between weight status and 1-year lagged fitness domains. Results: The sample included 917,554 children (51.8% male, 39.3% Hispanic, 29.9% non-Hispanic Black, 13.9%, 4.7%, and 1.7% class I, II, and III obesity, respectively). For each fitness domain, fitness scores decreased with increasing weight status across all demographic categories, with the lowest fitness scores observed in children with the most severe obesity, and highest magnitude of effects for aerobic capacity, and particularly among boys, non-Hispanic Whites, and older youth. For example, compared with youth with healthy weight, youth with overweight had 0.28 standard deviation lower aerobic capacity performance [confidence interval (95% CI): -0.29 to -0.28], followed by class 1 obesity (β = -0.57, 95% CI: -0.58 to -0.57), class 2 obesity (β = -0.88, 95% CI: -0.88 to -0.88), and class 3 obesity (β = -1.19, 95% CI: -1.20 to -1.18). Conclusions: Compared with youth with healthy weight, youth at every other weight status had lower subsequent fitness, with the magnitude of the relationship increasing as weight status increased. Future research should examine interventions targeting aerobic capacity to reduce fitness disparities.

Daily Physical Education Linked to Higher Youth Aerobic Fitness Levels: A 4-Year Longitudinal Study

PURPOSE

Physical education (PE) provides opportunities for youth physical activity during the school day, yet daily PE policies remain low. This study investigated whether daily PE was linked to youth aerobic capacity across a 4-year period in Greenville (South Carolina).

METHODS

Youth in grade levels second to eighth at 2 schools providing daily PE and 2 schools that did not provide daily PE participated in the study (N = 466). The 2 schools used as comparisons provided standard PE outlined by South Carolina, which included one 50-minute session per week (elementary) and daily PE for one semester (middle school). Aerobic fitness was measured using the FITNESSGRAM® Progressive Aerobic Cardiovascular Endurance Run test (May 2011-2015). Number of Progressive Aerobic Cardiovascular Endurance Run laps completed, age, gender, ethnicity, body composition, and school attended were included in multilevel linear regression analyses.

RESULTS

Across the sample, aerobic fitness increased with age. Throughout the study, males demonstrated growth in aerobic fitness compared with a slight decline for females (P < .001). Youth participation in daily PE was linked to increases in aerobic fitness compared with youth who did not receive daily PE (P < .001).

CONCLUSIONS

Findings suggest that exposure to daily PE may contribute to increased aerobic fitness in youth.

Low birth weight and its relation to physical fitness parameters in children: Its negative effect on muscle strength and cardiorespiratory endurance

BACKGROUND

There is increasing evidence that low birth weight has a negative effect on physical fitness, muscle strength, and cardiorespiratory endurance, although the findings are inconsistent.

OBJECTIVES

This study aimed to evaluate whether birth weight acts as a prenatal determinant of physical fitness parameters and to determine the role of environmental or biological variables on this effect.

METHODS

One hundred and sixty-seven children aged 6-14 years were included in this study. The anthropometric data, physical activity index, standing long jump, flexibility, handgrip strength, and cardiorespiratory fitness were evaluated.

RESULTS

A positive correlation was found between birth weight and cardiorespiratory fitness (r = .349; p < .001), right handgrip strength (r = .337; p < .001), and left handgrip strength (r = .320; p < .001), suggesting that children with low birth weight had the worst performance in both cardiorespiratory endurance and grip strength tests. These findings remained significant after adjustment for prematurity, sex, age, physical activity index, and body mass index (BMI). Stepwise multiple regression analyses revealed a significant interaction of high birth weight, older age, and low BMI in predicting better cardiorespiratory endurance (R² = .308). When handgrip strength was tested as the dependent variable, we found that high birth weight, male sex, and older age emerged as important determinants for both sides.

CONCLUSION

Children aged 6-14 years born with a birth weight < 2.5 kg have low handgrip strength and cardiorespiratory fitness, which seems to be mediated partially by influences of both prenatal environment (e.g., birth weight) and biological variables (e.g., age, sex, BMI).

Disparities in physical fitness of 6-11-year-old children: the 2012 NHANES National Youth Fitness Survey

Background

Children’s physical fitness is an important predictor of metabolic health, physical function, and academic achievement. Although fitness is determined partially by heritable factors, it can be maintained and improved through regular physical activity. Because physical activity is known to vary by socioeconomic status, physical fitness may be expected to vary similarly. With this in mind, the purpose of this study was to examine disparities in physical fitness performance among a nationally-representative sample of 6–11 year-old children living in the United States.

Methods

We conducted secondary analysis of physical fitness data of children ages 6–11 years (n = 686) from the nationally representative National Health and Nutrition Survey (NHANES) Youth Fitness Survey (NNYFS) 2012. We estimated sex-stratified weighted means of four fitness performance tests: cardiorespiratory endurance, upper-, lower-, and core-muscular strength. The weighted mean for each fitness assessment was compared by income groups (federal income to poverty ratio – FIPR) accounting for complex sampling design and adjusting for age.

Results

Income disparities in physical fitness performance were evident among girls but not among boys. Girls from lower income groups (< 130% FIPR and 130–349% FIPR groups) showed significantly lower cardiorespiratory endurance and core muscle strength compared to those from the highest income group (≥ 350% FIPR).

Conclusion

These findings highlight the need to support health-promoting physical activity among girls from disadvantaged backgrounds prior to the adolescent period.

Athletes for life: Rationale and methodology of a community- and family-based randomized controlled trial to promote cardiovascular fitness among primarily Latino families

BACKGROUND

Community-based programs have had modest success in combating obesity in Latino populations. Latino families' norms and beliefs about weight often hold larger body sizes to be normal, leading to lower engagement in weight-focused programs. Because improvements in cardiorespiratory fitness confer health benefits, regardless of weight, they offer an alternative to obesity-focused approaches. We describe the rationale and design of Athletes for Life (AFL), a community- and family-based intervention for Latino families.

METHODS/DESIGN

This two-group randomized controlled trial will test the efficacy of AFL for improving cardiorespiratory fitness and diet in 6- to 11-year-old children (N = 160) and their parents, relative to a wait-list control group. Children will participate in 12 weeks of semiweekly sports skill programing and nutrition sessions. Concurrently, parents will participate in sports-focused activity and behavior change sessions that focus on nutrition, chronic disease prevention, and healthy eating. Cardiovascular fitness will be measured by the 1-mile run and 3-min step-test for both parents and children. Secondary outcomes include changes in objectively measured physical activity, dietary measures, body composition, and cardiometabolic risk (waist circumference, blood pressure, blood lipids, glucose, insulin, and C-reactive protein).

DISCUSSION

AFL, implemented with a strong community partnership, will provide a test of the efficacy of culturally tailored intervention programming to promote positive health behaviors and improve health outcomes in Latino families. Intervention content, structure, and messaging will provide guidance for future methods to engage Latino families in health promotion programs that highlight their cultural norms, and beliefs.

TRIAL REGISTRATION

Clinicaltrials.gov Identifier NCT03761589 (12/3/2018).

Association between 9-minute walk/run test and obesity among children and adolescents: evidence for criterion-referenced cut-points

Background

Criterion-referenced cut-points for field-based aerobic fitness for children and adolescents are lacking. This study aimed to determine the associations between aerobic fitness and obesity to propose criterion-referenced cut-points for boys and girls (6–17 years).

Methods

A total of 61,465 children and adolescents aged 11.2 ± 2.0 years were recruited from 27 sites (all 26 states and Federal District) across Brazil. Aerobic fitness was assessed using 9-min walk/run test reported as distance attained during the test. Body mass index was calculated from measured height and weight and was used to identify obesity.

Results

The distance covered in the 9-min walk/run test (area under curve > 0.65) had satisfactory predictive ability for obesity. Sensitivity and specificity were moderate (>60%) to strong (>70%) for all age- and sex-specific cut-points. For boys, the optimal physical performance cut-points were, approximately, 1,200 m from 6 to 8 years, 1,300 m from 9 to 11 years, 1,380 m from 12 to 14 years, 1,520 m from 15 to 17 years. For girls, the best cut-points were, approximately, 1,070 m from 6 to 8 years, 1,160 m from 9 to 11 years and 1,200 m from 12 to 17 years.

Conclusions

The 9-min walk/run test had satisfactory predictive ability for obesity in children and adolescents. The physical fitness cut-points proposed in the present study varied according to age and sex and could be useful and practical tools to identify low levels of physical fitness in children and adolescents in Brazil.

Weight status perception and weight loss intention among urban youth

AIM

We explored associations of weight perception with measured weight status and weight loss intention among urban youth.

METHODS

This community surveillance project included 317 youth (10-19 years, 64% black) who answered YRBSS questions and underwent measurements of height and weight.

RESULTS

Weight misperception was observed among 47% of participants; 41% underestimated and 6% overestimated their weight status. Among youth with overweight and obesity, however, 72% misperceived their weight status; those with accurate perception were more likely to report trying to lose weight.

CONCLUSION

Addressing weight status misperceptions may be essential when advocating lifestyle behavior change to promote healthful body weight among youth.

Investigating the relationship between district-level socioeconomic status and individual obesity in Taiwanese adolescents: A large-scale cross-sectional analysis

The current study aimed to assess the prevalence of obesity and to explore the relationship between socioeconomic status and obesity among adolescents in Taiwan, a transitioning country. Data from the Taiwan School Physical Fitness Database on 1,875,627 Taiwanese adolescents aged 10-18 years were analyzed. The average family income per household in each district was collected from the national statistical institutional database. Descriptive statistics, Chi-square tests, Pearson correlation analysis, and mixed model analyses were used. The overall prevalence of combined overweight and obesity was 28.1%. The prevalence of overweight/obesity significantly differed according to gender and age. Furthermore, the average family income per household was negatively associated with the district-level prevalence of obesity. Additionally, when controlling for physical fitness, the average family income per household remained negatively associated with adolescent obesity. In addition, multilevel analysis was also applied to explore the relationship between district-level socioeconomic status and individual-level obesity to prevent the nested data structure from affecting the results. The results revealed that the average family income per household negatively correlated with individual obesity. These findings provide insight for public health officials into preventing and managing adolescent obesity.

Failure to meet aerobic fitness standards among urban elementary students

The aim of this study was to explore the relationship of aerobic fitness with the elementary school environment and student characteristics among 4th and 5th grade children attending urban public schools in St. Louis, MO, USA. This cross-sectional study was conducted during 2012–2015 and included 2381 children (mean age 10.5 y) who completed the FITNESSGRAM® 20-m Progressive Aerobic Cardiovascular Endurance Run. Healthy Fitness Zone (HFZ) was defined according to FITNESSGRAM® aerobic capacity criteria. Other student-level variables included age, race, National School Lunch Program eligibility, BMI z-score, weight status, and daily pedometer steps. School environment variables included playground features and playground safety, physical education and recess practices, and school census tract data on vacant houses and median household income. Bivariate analyses with sex stratification were used to identify student-level and school-level predictors of failure to achieve the aerobic HFZ; predictors were then included in a multivariable logistic regression model. Failure to meet the aerobic HFZ was observed among 33% of boys and 57% of girls. School environment was not predictive, but higher age and fewer daily steps were: each additional year of age was associated with 41% higher odds of failing to meet the aerobic HFZ among boys and 100% higher odds among girls. Conversely, each additional 1000 daily steps was associated with 15% (boys) and 13% (girls) lower odds of failure. Obesity posed a 60% higher risk of failure to meet HFZ among girls. These results highlight the importance of childhood physical activity opportunities, especially for girls residing in low-resource areas.

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Aerobic fitness was assessed with the FTINESSGRAM 20-m run in urban students.

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Many urban elementary students failed to meet Healthy Fitness Zone (HFZ) criteria.

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Girls with obesity (vs. healthy weight) were 60% more likely to fail to meet HFZ.

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School environment was not associated with failure to meet aerobic criteria.

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Schools should provide frequent high-quality physical education and activities.

Cardiorespiratory fitness in children: Evidence for criterion-referenced cut-points

INTRODUCTION

Criterion-referenced cut-points for field-based cardiorespiratory fitness for children (CRF) are lacking. This study determined: (a) the association between CRF and obesity, (b) the optimal cut-points for low CRF associated with obesity in children, and (c) the association between obesity and peak oxygen uptake ([Formula: see text]) estimated from the 20-m shuttle run test using two different prediction equations.

METHODS

A total of 8,740 children aged 10.1±1.2 were recruited from 11 sites across Canada. CRF was assessed using 20mSRT reported as running speed at the last completed stage, number of completed laps and predicted [Formula: see text], which was estimated at the age by sex level using the Léger et al. and FitnessGram equations. Body mass index and waist circumference z-scores were used to identify obesity. Receiver operating characteristic (ROC) curves and logistic regression determined the discriminatory ability of CRF for predicting obesity.

RESULTS

20mSRT had satisfactory predictive ability to detect obesity estimated by BMI, WC, and BMI and WC combined (area under the curve [AUC]>0.65). The FitnessGram equation (AUC>0.71) presented somewhat higher discriminatory power for obesity than the equation of Léger et al. (AUC>0.67) at most ages. Sensitivity was strong (>70%) for all age- and sex-specific cut-points, with optimal cut-points in 8- to 12-year-olds for obesity identified as 39 mL•kg-1•min-1 (laps: 15; speed: 9.0 km/h) and 41 mL•kg-1•min-1 (laps: 15-17; speed: 9.0 km/h) for girls and boys, respectively.

CONCLUSIONS

20mSRT performance is negatively associated with obesity and CRF cut-points from ROC analyses have good discriminatory power for obesity.

BMI-for-age graphs with severe obesity percentile curves: tools for plotting cross-sectional and longitudinal youth BMI data

Background

Severe obesity is an important and distinct weight status classification that is associated with disease risk and is increasing in prevalence among youth. The ability to graphically present population weight status data, ranging from underweight through severe obesity class 3, is novel and applicable to epidemiologic research, intervention studies, case reports, and clinical care.

Methods

The aim was to create body mass index (BMI) graphing tools to generate sex-specific BMI-for-age graphs that include severe obesity percentile curves. We used the Centers for Disease Control and Prevention youth reference data sets and weight status criteria to generate the percentile curves. The statistical software environments SAS and R were used to create two different graphing options.

Results

This article provides graphing tools for creating sex-specific BMI-for-age graphs for males and females ages 2 to <20 years. The novel aspects of these graphing tools are an expanded BMI range to accommodate BMI values ˃35 kg/m², inclusion of percentile curves for severe obesity classes 2 and 3, the ability to plot individual data for thousands of children and adolescents on a single graph, and the ability to generate cross-sectional and longitudinal graphs.

Conclusions

These new BMI graphing tools will enable investigators, public health professionals, and clinicians to view and present youth weight status data in novel and meaningful ways.

Electronic supplementary material

The online version of this article (doi:10.1186/s12887-017-0885-x) contains supplementary material, which is available to authorized users.

Obesity Epidemiology Worldwide

Obesity continues to be a public health concern across the globe. Obesity has a demonstrated association with health behaviors and health outcomes, such as diabetes, hypertension, and cancer. Over the past 2 decades, obesity has increased worldwide and remains highest in the United States. It is critical to understand the definition of obesity, using body mass index appropriately, recent estimates, and risk factors as a framework within which clinicians should work to help reduce the burden of obesity. This framework, including the Healthy People 2020 place-based approach to social determinants of health, is described in this article.

Meals of differing caloric content do not alter physical activity behavior during a subsequent simulated recess period in children

OBJECTIVE

Research on adults and animals has demonstrated that chronic and acute overfeeding can alter physical activity behavior. However, there are no assessments of the acute effects of high-calorie (HC) meals on physical activity behavior in children. This is of importance as a typical school lunch is HC. If this type of meal negatively impacts subsequent physical activity behavior, the ability of post-lunch recess periods as a means to increase energy expenditure may be lessened.

PURPOSE

To assess the effect of two meals of differing caloric content, HC and low calorie (LC), on children's subsequent physical activity behavior.

METHODS

Nineteen healthy children (aged 6-10) completed two laboratory sessions where they were fed lunch with HC or LC content, but equivalent macronutrient distribution. Children had 15 min to consume as much of the meal as possible per session. Children consumed 659.5 ± 101.3 kcal in the HC condition and 291.8 ± 12.1 kcal in the LC condition. After the meal, children went to a gymnasium for 40 min. In the gymnasium children had free-choice access to obstacle courses, various sports equipment, and a table with sedentary activities. Children could play with any of the activities in any amount they wished for the entire activity session. Children's physical activity was monitored with accelerometers and that data was converted into caloric expenditure. Each child ate all meals and participated in the free-choice activity sessions with no other children present.

RESULTS

Caloric expenditure during the free-choice activity sessions was not significantly different (p = 0.4) between the HC (89.2 ± 27.3 kcals) and LC (83.4 ± 34.9 kcals) conditions. However, caloric balance (kcals eaten-kcals expended) was 2.74-fold greater (p < 0.001) in the HC condition (Δ 570.3 ± 92.2 kcals) than the LC condition (Δ 208.4 ± 32.0 kcals).

CONCLUSION

Children did not alter their physical activity behavior during a free-choice activity session after consuming a HC meal versus a LC meal. Because activity was not different across the two conditions, children had a much greater caloric surplus during the HC condition than the LC condition.