National Youth Fitness Survey Research Articles

Association of Recess Provision With Accelerometer-Measured Physical Activity and Sedentary Time in a Representative Sample of 6- to 11-Year-Old Children in the United States.

To assess the association between the amount of recess provision and children's accelerometer-measured physical activity (PA) levels. Parents/guardians of 6- to 11-year-olds (n = 451) in the 2012 National Youth Fitness Survey reported recess provision, categorized as low (10-15min; 31.9%), medium (16-30min; 48.0%), or high (>30min; 20.1%). Children wore a wrist-worn accelerometer for 7days to estimate time spent sedentary, in light PA, and in moderate to vigorous PA using 2 different cut points for either activity counts or raw acceleration. Outcomes were compared between levels of recess provision while adjusting for covariates and the survey's multistage, probability sampling design. Children with high recess provision spent less time sedentary, irrespective of type of day (week vs weekend) and engaged in more light or moderate to vigorous PA on weekdays than those with low recess provision. The magnitude and statistical significance of effects differed based on the cut points used to classify PA (eg,4.7 vs 11.9 additional min·d-1 of moderate to vigorous PA). Providing children with >30minutes of daily recess, which exceeds current recommendations of ≥20minutes, is associated with more favorable PA levels and not just on school days. Identifying the optimal method for analyzing wrist-worn accelerometer data could clarify the magnitude of this effect.

Associations Between Intersecting Sociodemographic Characteristics and Device-Measured Physical Activity Among Children and Adolescents Living in the United States.

Despite robust evidence demonstrating sociodemographic characteristics may underly some of the disparities in physical activity observed among children and adolescents, the often-overlooked nexus of potential interactions between these characteristics warrants further exploration. This study explored the intersectionality of gender, race/ethnicity, parental education, and household income in relation to device-measured physical activity volume and intensity in a nationally representative sample of US children and adolescents. Cross-sectional data from 3 cycles of the US National Health and Nutrition Survey (2011-2012; 2012 National Youth Fitness Survey; and 2013-2014) were used. A total of 6116 participants (49% female) between 3 and 17years of age wore an accelerometer on their nondominant wrist for 7days. Monitor-independent movement summary units were used to represent physical activity volume and intensity. A Social Jeopardy Index was created to represent increasing levels of intersecting social disadvantages based on combinations of gender, race/ethnicity, parental education, and household income-to-poverty ratio tertiles. Generalized linear regression models were computed. The results showed social disadvantages become increasingly evident among children and adolescents during the most intense 60minutes of daily physical activity (B = -48.69 [9.94] SE, P < .001), but disparities in total volume were not observed (B = 34.01 [44.96] SE, P = .45). Findings suggest that patterns of physical activity behavior may differ based on intersecting sociodemographic characteristics-more socially disadvantaged children and adolescents appear to accumulate activity at lighter intensities. Collecting contextual information about device-measured physical activity represents an important next step for gaining insight into these sociodemographic differences.

Have the Fundamental Movement Skills of U.S. Children Changed?

ABSTRACT Purpose: By using four national data sets, this study aimed to examine the changes in U.S. children’s fundamental movement skills (FMS) from 1985 to 2019. Method: Three Tests Gross of Motor Development (TGMD) normative studies, i.e. TGMD-1 (N = 909, male% = 50), TGMD-2 (N = 1143, male% = 50) and TGMD-3 (N = 864, male% = 51), and the TGMD-2 data of the 2012 NHANES National Youth Fitness Survey (NNYFS-2012; raw N = 352, national represented population = 12,509,706, male% = 51) were used for analyses. Each item in TGMD-2/NNYFS and TGMD-3 was carefully examined, and these that did not match to TGMD-1 were deleted. Cohen’s D effect size (ES) was utilized for the difference among year-to-year comparisons. Result: From 1985 to 2000, FMS in US children of 3–7 years old (90% increase & 10% no change) increased temporarily, but remained stable (17% increase & 83% no change) among 8–10 years old. Between 2000 and 2019, however, U.S. children began to demonstrate a slight/stable drop in FMS among 3–5 years old (22% decrease & 78% no change), and a distinct decline among 6–10 years old (80% decrease & 20% no change). While children with normal BMI showed the highest FMS score, the direct cause of reduction in FMS is still unknown. Conclusion: An overall up-and-down change was observed in U.S. children’s FMS between 1985 and 2019, and more longitudinal studies with FMS-related variables are needed.

Associations of Monitor-Independent Movement Summary and Health-Related Fitness With Gross Motor Skills in Young Children

The purpose of this study was to determine the associations of device-based assessments of physical activity (PA) and health-related fitness (HRF) with gross motor skills (GMS) in preschool-aged children. Participants were 3- to 5-year-old children (N = 316; 49.6% female) who participated in the 2012 National Youth Fitness Survey. GMS was assessed using the gross motor quotient calculated from the Test for Gross Motor Development—Second Edition. PA was assessed using wrist-worn ActiGraph GT3X accelerometers with raw triaxial acceleration data summarized using monitor-independent movement summary units (MIMS). Analyzed metrics included average MIMS per day and peak 30-min MIMS. HRF assessment consisted of a plank score and a sum of skinfold assessment. Weighted hierarchical regressions tested the associations between PA, HRF, and GMS variables with a secondary weighted mediation analysis that examined whether HRF mediated the association between PA and GMS. Peak 30-min MIMS significantly correlated with GMS (b = 0.17, p = .005). Plank scores had the strongest correlation with GMS (b = 0.23, p = .004), and weighted mediation analyses revealed that plank scores partially mediated the association between peak 30-min MIMS and GMS (indirect effect = 0.03, p = .01, 23.1% mediation). Peak 30-min MIMS significantly associated with GMS in preschool children, an association partially mediated by core muscular endurance.

Dose-response associations of Monitor-Independent Movement Summary with health-related fitness in youth.

The purpose of this study was to determine the dose-response associations between Monitor-Independent Movement Summary (MIMS) units and health-related fitness in youth. The sample comprised US children and adolescents who participated in the 2012 National Youth Fitness Survey (NNYFS; N = 1158, 48.9% female). Health-related fitness domains were assessed using tests of cardiorespiratory endurance (timed maximal and graded treadmill tests), muscular strength (modified pull-up and grip tests), and muscular endurance (plank test). Movement data were collected using wrist-worn ActiGraph accelerometers with raw data processed using MIMS and the calculated metrics of average MIMS/day, Peak 60-min MIMS, and Peak 30-min MIMS. Weighted regression models examined linear associations between MIMS metrics and fitness test scores. Nonlinear associations were examined using weighted spline models with knots placed at the 10th, 50th, and 90th percentiles. Models were adjusted for covariates and fit was examined using the coefficient of determination (R2 ). The strongest adjusted linear relationships included a positive association between MIMS/day (per every 1000 units) and maximal endurance times (b = 5.5 s, p < 0.001) and between Peak 60-min MIMS (per every 10 units) and estimated aerobic capacity (b = 1.7 mL/kg/min, p < 0.001), modified pull-ups (b = 0.7 reps, p < 0.001), and plank test scores (b = 5.0 s, p < 0.001). Linear spline models had slightly higher R2 values (R2 range = 16.9%-74.8%) compared to linear models (R2 range = 15.0%-74.5%). The relationship between MIMS metrics and fitness test scores was best modeled as piecewise linear functions. Although all MIMS metrics associated with cardiorespiratory endurance, Peak 60-min MIMS showed stronger associations with tests of muscular strength and endurance.

Adherence to Recess Guidelines in the United States Using Nationally Representative Data: Implications for Future Surveillance Efforts.

National adherence to the recess recommendations of the Centers for Disease Control and Prevention (CDC) has not been comprehensively studied in the United States. Data from 6 nationally representative data sets over the last decade (Classification of Laws Associated with School Students, Early Childhood Longitudinal Study, National Health and Nutrition Examination Survey, National Youth Fitness Survey, School Health Policies and Practices Survey, and the School Nutrition and Meal Cost Study) provided estimates for adherence to CDC recess guidelines. While approximately 65-80% of elementary school-children receive the recommended 20+ minutes of daily recess according to parent-, principal-, and school-report, adherence declines by sixth grade, and little information is available for middle/high school students. Adherence to playground safety was high (90%), but adherence to recommendations about recess before lunch (<50%), withholding recess as punishment (∼50%), and training recess staff (<50%) were lower. School policy and practice should align with CDC recommendations, with the aim of providing sufficient quality recess to all youth, K-12th grade. Comprehensive, on-going national surveillance of multiple recess domains is needed to inform policy and ensure equitable provision of recess.

Association of Recess Provision With Elementary School-Aged Children's Physical Activity, Adiposity, and Cardiorespiratory and Muscular Fitness.

To identify associations between amount of school recess provision and children's physical activity (PA), weight status, adiposity, cardiorespiratory endurance, muscular strength, and muscular endurance. Data from 6- to 11-year-old participants (n = 499) in the 2012 National Youth Fitness Survey were analyzed. Parents/guardians reported children's PA levels and recess provision, categorized as no/minimal (9.0%), low (26.1%), medium (46.0%), or high (18.9%). Children wore a wrist-worn accelerometer for 7days and completed anthropometric measurements. Fitness was assessed using grip strength and treadmill, pull-up, and plank tests. Cross-sectional linear and logistic regression compared outcomes across levels of recess provision adjusting for the survey's complex sampling design. Children with high provision of recess were 2.31 times more likely to meet PA guidelines according to parent report than those with no/minimal recess. Accelerometer-measured PA followed a more U-shaped pattern, wherein PA was higher in children with high, compared to low, recess provision but comparable to those with no/minimal recess provision. There were no associations with weight status, adiposity, or fitness. Current recess recommendations (20min·d-1) may be insufficient as 30minutes per day of recess was associated with a 2-fold greater likelihood of achieving recommended PA levels. Additional research on recess quantity and quality is needed.

Physical Activity among U.S. Preschool-Aged Children: Application of Machine Learning Physical Activity Classification to the 2012 National Health and Nutrition Examination Survey National Youth Fitness Survey.

Early childhood is an important development period for establishing healthy physical activity (PA) habits. The objective of this study was to evaluate PA levels in a representative sample of U.S. preschool-aged children. The study sample included 301 participants (149 girls, 3–5 years of age) in the 2012 U.S. National Health and Examination Survey National Youth Fitness Survey. Participants were asked to wear an ActiGraph accelerometer on their wrist for 7 days. A machine learning random forest classification algorithm was applied to accelerometer data to estimate daily time spent in moderate- and vigorous-intensity PA (MVPA; the sum of minutes spent in running, walking, and other moderate- and vigorous-intensity PA) and total PA (the sum of MVPA and light-intensity PA). We estimated that U.S. preschool-aged children engaged in 28 min/day of MVPA and 361 min/day of total PA, on average. MVPA and total PA levels were not significantly different between males and females. This study revealed that U.S. preschool-aged children engage in lower levels of MVPA and higher levels of total PA than the minimum recommended by the World Health Organization.

Site And Unit: Two Flaws Of Physical Activity Assessment In NHANES National Youth Fitness Survey

PURPOSE: To explore possible flaws in physical activity (PA) assessment in the 2012 NHANES National Youth Fitness Survey (NNYFS 2012) that led to a very high PA passing rate. METHOD: The weighted physical activity data (N = 11,223,647, 51% boys, for 3-5 yr. old) collected using ActiGraph in NNYFS 2012 were analyzed to determine the prevalence of meeting the recommendation of the PA guidelines. Specifically, after the released data in Monitor-Independent Movement Summary (MIMS) unit were converted to the MIMS-EQ-Count, an equivalent of ActiGraph count, based on the results of a test equating study by Qin et al. (2021), the prevalence was computed using the cutoff scores by Johansson et al. (2016) for 3-5 yr. old. RESULTS: Unexpected, very high pass rates (%) were observed based on the daily 120 min (SHAPE America, 2020) moderate and vigorous PA (MVPA) and 180 min PA, including 60 min MVPA (WHO, 2019) cutoffs (Boys, Girls, Total):The higher passing rates observed were likely caused by the wrist site, where ActiGraph was worn, employed in NNYFS 2012 and the noise movements by hands (e.g., playing the computer games) that were mistakenly classified as MVPA. Using MIMS, rather than ActiGraph counts, as the unit of the data was another problem since MIMS’ PA intensity cutoff scores have not been established and validated. Together, due to failing to create trustful MVPA data, these two flaws made PA data from NNYFS 2012 less meaningful and useful. CONCLUSION: The very high prevalence of US children meeting PA recommendations was likely caused by two major flaws when collecting PA by wearing ActiGraph on wrist and releasing the data in MIMS unit.

Ultraprocessed Food Intake Is Associated With Poor Cardiovascular Fitness in US Children and Adolescents

ObjectivesUltraprocessed food intake is an established risk factor for cardiovascular disease in adults, however few studies have examined the association between intake of ultraproecssed foods during childhood and risk for cardiovascular disease. The objective of this study was to determine the association between eating patterns, specifically consumption of ultraprocessed foods, and markers of physical fitness in a nationally representative sample of children and youth. MethodsUsing data from NHANES National Youth Fitness Survey, the association between ultraprocessed food consumption and cardiovascular fitness level was evaluated. During the NNYFS, cardiovascular fitness was assessed in adolescents aged 12–15 y and locomotor development was assessed in children age 3–5. Dietary intake information was collected using 24-hour recall; recalled foods were classified using the NOVA classification system and NOVA Category 4 (ultraprocessed) were identified. Cardiovascular fitness level was categorized based on gender-age specific cut-points of estimated VO2max. All data were analyzed using SAS 9.4 survey procedures to account for the unequal sampling probability and complex survey design of the. ResultsIn older children, we observed a significant positive association between consumption of ultraprocessed foods and cardiovascular fitness level after controlling for age, sex, race, and household income. Children with cardiovascular fitness levels categorized as “high risk” consumed approximately 200kcal more/day of ultraprocessed foods than children in the “healthy fitness zone”, p = 0.002. In younger children, greater intake of ultraprocessed foods was associated with lower locomotor development score; children with the lowest locomotor development scores consumed 273kcal/more day of ultraprocessed foods than children with the highest locomotor development scores, p = 0.0006. ConclusionsThese findings expand on previous work from our group evaluating the association between childhood eating behaviors and fitness indicators. Interventions that aim to educate families about cost-effective methods of reducing ultraprocessed food intake may assist in decreasing risk for cardiovascular health problems in adulthood. Funding SourcesNone.

Cross-sectional association of light sensor-measured time outdoors with physical activity and gross motor competency among U.S. preschool-aged children: the 2012 NHANES National Youth Fitness Survey

BackgroundTime spent outdoors (outdoor time) has been suggested to be beneficial for physical activity (PA) and healthy development among preschool-aged children. The aim of this study was to quantify PA level and gross motor competency associated with light sensor-measured daily outdoor time in a representative sample of U.S. children aged 3 to 5 years.MethodsThe study sample included 301 participants (149 girls) aged 3 to 5 years from the 2012 U.S. National Health and Examination Survey National Youth Fitness Survey. ActiGraph GT3X+ accelerometers with a built-in ambient light sensor were used to measure PA (expressed in monitor-independent movement summary [MIMS]) and outdoor time. The Test of Gross Motor Development-Second Edition (TGMD-2) was used to assess gross motor skills. Multivariable linear regression models were fit to predict daily and gross motor scores by daily outdoor time.ResultsAverage daily outdoor time was 95 min (median of 84 min; interquartile range of 52 to 123 min). Means of daily outdoor time and daily MIMS were not significantly different between boys and girls. Among girls, every additional 10 min of daily outdoor time was associated with an additional 540 daily total MIMS (95% CI = 372, 708). Among boys, every additional 10 min of daily outdoor time was associated with an additional 296 daily total MIMS (95% CI = 131, 460). Every additional 10 min of daily outdoor time was associated with a 0.1-point (95% CI = 0.001, 0.130) higher object control standard score. Daily outdoor time was not associated with a locomotor standard score.ConclusionsIn a representative sample of U.S. preschool-aged children, daily outdoor time was positively associated with daily PA. The contribution of outdoor time to PA was greater among girls than boys, suggesting that providing outdoor opportunities is critical for promoting PA, particularly among girls.

Shifting Patterns of BMI and Skinfold Fatness among US Children: 1985/87 vs. 2012

&#x0D; Background: Childhood obesity has been recognized as a major public health concern. The purpose of this study was to determine specific shifting patterns of BMI and skinfold fatness across different age and sex groups between 1985/87 and 2012.&#x0D; Methods: The data of 9,366 children aged 8-15 years from two nationally representative surveys, i.e., 1985/87 National Children and Youth Fitness Study I &amp; II and 2012 National Health and Nutrition Examination Survey National Youth Fitness Survey, were analyzed. Specifically, changes of BMI-based obesity prevalence and shifting patterns of BMI, height, weight, skinfold body fat percentage (skinfold-fat%), subscapular skinfold, and triceps skinfold from 1985/87 to 2012 were estimated by age and sex using the 1985/87 quartiles as the baseline.&#x0D; Results: Significantly increased obesity prevalence were reconfirmed for both boys (12.12%, P &lt;.001) and girls (3.53%, P &lt;.001) from 1985/87 to 2012. Except for height, all other measures in 2012 experienced an unbalanced shifting pattern, mainly from other quartiles into the 4th quartile of 1985/87.&#x0D; Conclusion: The shifting of both boys’ and girls’ BMI and skinfold-fat% were all concentrated in the 4th quartile of 1985/87, indicating not only that there was a significant increase in BMI and skinfold-fat% in the U.S. children from 1985/87 to 2012, but also into the overweight and obese subgroups, which serves as a serious warning for childhood obesity epidemic and public health.&#x0D;

Fundamental Motor Skill Delays in Preschool Children With Disabilities: 2012 National Youth Fitness Survey

Delays in fundamental motor skill (FMS) competency have been observed in a variety of children with disabilities. However, evidence of FMS delays is largely limited to small, geographically specific, limitedly diverse, and non-representative samples. The purpose of this study was to examine the association between FMS competency and reported disability status among pre-school children, ages 3–5 years, using the 2012 National Youth Fitness Survey (NYFS). In total, 329 preschool children (49% female; 4.00 ± 0.04 years of age) from the 2012 NYFS completed the Test of Gross Motor Development−2, including 43 preschoolers identified with a disability based on parental report (44% female; 4.20 ± 0.16 years). Associations were examined with logistic regression using sampling weights. Poor FMS competency, defined as gross motor quotient scores ≤ 79, was observed in significantly more children with disabilities (29%) than children without disabilities (10%, OR = 3.5, p = 0.04). While not statistically significant, there was a growing disparity in FMS competency at age 5 (41 vs. 11%) compared to age 3 (15 vs. 9%, OR = 1.80, p = 0.30). The results provide additional evidence for poor FMS competency among pre-school children with disabilities. FMS should be an early part of comprehensive assessments for all children suspected of disability or development delay as it is critical to identify and intervene upon FMS delays before discrepancies can widen.

Associations of Percent Body Fat and Motor Skill Development in Preschool-Aged Children: National Youth Fitness Survey.

Background: Body composition and motor skill development are important for the engagement in physical activity and healthy development of children. This study examined the associations between body composition and motor skill development in 3- to 5-year-old children. Methods: Data from preschool-aged children (N = 342, 51% males) who participated in the 2012 National Youth Fitness Survey were analyzed. Skinfold measurements (subscapular, calf, and triceps) were taken and percent body fat (%BF) was calculated using sex-specific equations. Lean muscle mass and fat mass were also calculated. Motor skill development was determined by the Test of Gross Motor Development-2nd Edition. Regression analyses were performed to determine the associations among %BF and locomotor skills, object control skills, and overall gross motor quotient (GMQ), controlling for sex, race, and poverty index ratio. Results: Most children were classified as with underweight/healthy weight (69%) and 31% were either with overweight or obesity. Average %BF was 17.02% ± 0.27%. The standard scores for locomotor skills, object control skills, and GMQ were 9.99 ± 0.16, 8.52 ± 0.14, and 95.57 ± 0.68, respectively. These scores were considered average. Regression analyses indicated that neither the %BF nor sum of skinfolds was associated with locomotor skills (β = -0.07 ± 0.05, p = 0.63; β = -0.03 ± 0.03, p = 0.22), object control skills (β = 0.03 ± 0.04, p = 0.55; β = 0.00 ± 0.02, p = 0.87), or GMQ (β = -0.13 ± 0.28, p = 0.63; β = -0.09 ± 0.14, p = 0.52). Furthermore, neither lean muscle mass nor fat mass was related with any motor skill measure (p > 0.05). Conclusions: Using different measures of body composition may provide additional insight into associations between obesity and motor skill development in preschool-aged children. Given the inconsistent findings in the literature, additional research is needed to elucidate these associations.

Lower Musculoskeletal Fitness Among Children With Disabilities, Ages 6 To 15 Years: 2012 NYFS

Children with disabilities (CWD) are at increased risk for obesity, due in part to low rates of physical activity and poor physical fitness. CWD often exhibit deficits in musculoskeletal fitness, which may affect the ability to perform activities of daily living. However, much of the literature on fitness in CWD is limited by small, non-representative samples. PURPOSE: To examine differences in musculoskeletal fitness between children with and without disabilities from the 2012 National Youth Fitness Survey (NYFS). A secondary aim of the study was to examine factors related to poor musculoskeletal fitness. METHODS: A secondary analysis of cross-sectional data from the 2012 NYFS of children, 6 to 15 years of age. Fitness measures included plank (s), modified pull-ups (#), and grip strength (kg). Grip strength was standardized relative to body weight (kg/kg). Low fitness performance was defined as ≤20th percentile of age/sex specific reference curves (Laurson et al., 2016). Disability was identified by parent report of movement limitation, long-term impairment, use of specialized equipment, or special education services. Logistic regression with sampling weights was employed to examine group differences and associated factors. RESULTS: A total of 1,177 children (49% female, Mage = 10.5 ± 0.07) were analyzed, including 173 CWD (15%). A significantly greater proportion of CWD demonstrated low musculoskeletal fitness compared to children without disabilities (Table 1). Factors associated with low fitness included sex, engagement in physical activity, and body mass index category (p < .05). Age was not a significant factor for any fitness measure (p > .10). CONCLUSION: This secondary analysis provides additional evidence for lower musculoskeletal fitness among CWD, in particular for females and children with obesity. Physical fitness continues to be an area in need of intervention to improve overall health among CWD.a Proportion (95% CI) at ≤20th percentile.* p < .05

US Population-referenced Percentiles for Wrist-Worn Accelerometer-derived Activity.

This study aimed to present age- and sex-specific percentiles for daily wrist-worn movement metrics in US youth and adults. This metric represents a summary of all recorded movement, regardless of the purpose, context, or intensity. Wrist-worn accelerometer data from the combined 2011-2014 National Health and Nutrition Examination Survey cycles and the 2012 National Health and Nutrition Examination Survey National Youth Fitness Survey were used for this analysis. Monitor-Independent Movement Summary units (MIMS-units) from raw triaxial accelerometer data were used. We removed the partial first and last assessment days and days with ≥5% nonwear time. Participants with ≥1 valid day were included. Mean MIMS-units were calculated across all valid days. Percentile tables and smoothed curves of daily MIMS-units were calculated for each age and sex using the Generalized Additive Models for Location Shape and Scale. The analytical sample included 14,705 participants age ≥3 yr. The MIMS-unit activity among youth was similar for both sexes, whereas adult females generally had higher MIMS-unit activity than did males. Median daily MIMS-units peaked at age 6 yr for both sexes (males, 20,613; females, 20,706). Lowest activity was observed for males and females 80+ yr of age: 8799 and 9503, respectively. Population referenced MIMS-unit percentiles for US youth and adults are a novel means of characterizing total activity volume. By using MIMS-units, we provide a standardized reference that can be applied across various wrist-worn accelerometer devices. Further work is needed to link these metrics to activity intensity categories and health outcomes.

Cardiovascular Fitness and Muscle Strength in Asthmatic Children

The aim of this retrospective study is to evaluate the cardiovascular fitness and muscle strength performance of children with asthma versus without. Participants include patients who were involved in the 2012 NHANES National Youth Fitness Survey (NNYFS) as published by the Centers for Disease Control and Prevention. The average cardiovascular fitness and muscle strength scores will be appreciated by analyzing the averages of time spent on treadmill, maximal heart rate, heart rate at end of exam, recovery time, maximal endurance time, cardiovascular fitness report, upper body strength and lower body strength using two-tailed T-tests between patients with asthma versus without. Children with asthma have a statistically lower total time spent on treadmill and maximal endurance time (p = 0.006, p = 0.006, respectively). Children with asthma do not have statistically different maximal heart rate, heart rate at end of exam, recovery time, cardiovascular fitness, upper body strength, or lower body strength compared to children without asthma. History of asthma should not be considered a direct, baseline cause of decreased cardiovascular fitness or muscle strength performance in children. The anxiety of breathlessness in an asthma attack or lack of proper medical management may encourage asthmatics to have a sedentary lifestyle without engaging in regular physical activity. Our findings support the growing research that encourages the individuals with asthma to pursue a healthy, active lifestyle alongside proper medical management in order to achieve optimal cardiovascular and musculoskeletal health.

U.S. Children and Youth's Physical Activities Inside and Outside of School PE: 1985 vs. 2012.

The purpose of this study was, by taking advantage of the rich data from two U.S. national fitness surveys, to examine the physical activity (PA) students engaged in, both inside and outside school physical education (PE), determine if there are differences by grade, sex, and weight status, and if there was a change between 1985 and 2012. The data from the 1985 National Children and Youth Fitness Study (NCYFS) and the 2012 NHANES National Youth Fitness Survey (NNYFS) were matched, merged (N = 6178, 3107 boys and 3071 girls), and analyzed. It was found that basketball remained the most popular PA inside school PE across both surveys. Swimming was the most popular PA outside of school PE in 1985, but was replaced by running in 2012. Although PA taught and promoted inside of school PE and that such PA practiced outside were moderately correlated across the surveys, some disconnections were noticed. The impact of grade, sex, and weight status on PA preference and participation was also confirmed. What is needed is to the design and integration of more lifelong and individual PAs in future school PE curricula and school and community children and youth sport and PA programs.

Movement behaviors and health-related fitness among peripubertal adolescents: 2012 NHANES national youth fitness survey data.

Less than half of adolescents in the United States meet the recommended levels of moderate-to-vigorous physical activity (MVPA) and health-related fitness (HRF). Using the 2012 NHANES National Youth Fitness Survey data, this study aimed to examine the associations of movement behaviors (i.e., MVPA and screen-based sedentary behaviors) with HRF (i.e., cardiovascular and muscular fitness) among 11-16- year-old peripubertal boys and girls, respectively. A total of 470 adolescents (227 boys, 243 girls; age: 13.59±1.12 years old) from the 2012 NHANES dataset were included. The study variables included movement behaviors (i.e., MVPA and screen-based sedentary behavior), anthropometric indices (i.e., waist circumference, Body Mass Index [BMI]), and HRF (i.e., cardiovascular fitness and muscular fitness). Correlational and hierarchical regression analyses were conducted for boys and girls, respectively. MVPA significantly predicted cardiovascular fitness for boys (β=0.16, P<0.05) and girls (β=0.15, P<0.05) regardless of weight status; screen-based sedentary behavior and waist circumference in girls significantly predicted muscular fitness (β=-0.13 and β=-0.42, P<0.05). To increase overall HRF in peripubertal girls and boys, it is important to help them maintain healthy weight status and to promote MVPA and limit screen-based sedentary behavior, especially in adolescent girls.

Health Insurance Moderates the Waist Circumference and Cardiorespiratory Fitness Relationship in U.S. Adolescents

Background: Abdominal obesity is a cardiometabolic risk factor and shown to be related to cardiorespiratory fitness (CRF). The purpose of this study was to examine the moderating effects of health insurance (HI) on the waist circumference (WC) and CRF relationship in U.S. adolescents. Methods: Data from youths 12 to 15 years of age participating in the 2012 NHANES National Youth Fitness Survey (NNYFS) were used. Both WC (cm) and CRF (ml/kg/min) were measured by trained medical personnel with HI status assessed via questionnaire by proxy. Binary variables were created at the median for WC and CRF. Multivariate logistic regression was used to examine the relationship between WC, HI and CRF while controlling for confounding variables. Results: The overall prevalence of no HI was 6.5% (95% CI: 2.78 - 10.20). Findings from the fully adjusted model predicting low CRF showed a significant (p = .020) WC-by-HI interaction. Slicing the model by HI status showed a significant decreased risk of low CRF for adolescents with HI and low WC (OR = 0.25, 95% CI: 0.19 - 0.33). Additionally, a significant decreased risk of low CRF was seen among those with no HI and low WC (OR = 0.50, 95% CI: 0.28 - 0.88). Slicing the model by WC status showed a significant increased risk of low CRF for adolescents with low WC and no HI (OR = 2.44, 95% CI: 1.22 - 5.32). However, no significant HI and CRF relationship was observed among adolescents with high WC. Conclusion: This study showed that HI moderates the WC and CRF relationship in U.S. adolescents. Specifically, having low WC appears to protect adolescents against low CRF. Whereas having HI looks as if to protect against low CRF only for those with low WC.