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Motor competency is integral to the long-term athletic development of youths. Strength and conditioning (SC) coaches are recommended to deliver motor competency interventions, yet no studies have investigated their perceptions and practices for developing motor competency in youths. Sixty-seven male, and 4 female SC coaches completed an initial and follow up questionnaire using a 5-point Likert scale, rating 1] the importance of developing competence, and 2] how frequently they developed competence across 90 motor competencies. Over 55% of SC coaches reported a broad range of "important" (69/90) and "frequently developed" (48/90) motor competencies. The most important motor competency was "deceleration" (4.9 ± 0.3), whilst "hip hinge (bilateral)" was the most practised (4.4 ± 0.5). SC coaches targeted upper body pushing and pulling competencies more than their perceived importance, whilst agility (e.g., turning) competencies were targeted less than their importance. Further analysis showed SC coaches who delivered 3-4 sessions per week targeted 15-18% more competencies compared to ≤ 2 sessions per week. Overall, these findings have strong implications for youth motor competency development including the reflection of important vs. practised competencies, coach education programmes, and consideration for how SC coaches should seek to optimise motor competency development within youths.

Interpreting change in Body mass index (BMI) among youth by comparison to growth charts can be difficult because of maturation-related changes. The aim of this paper was to evaluate the uti...

As highlighted in this special issue, physical activity during childhood and adolescence is influenced by several factors including body size and composition, biological maturity, and motor skill d...

Fullagar, HHK, Harper, LD, Govus, A, McCunn, R, Eisenmann, J, and McCall, A. Practitioner perceptions of evidence-based practice in elite sport in the United States of America. J Strength Cond Res 33(11): 2897-2904, 2019-Practitioners' perceptions regarding the use and effectiveness of research evidence in sport is not well understood. The purpose of the present study was to examine practitioners' perceptions around the use, implementation, and barriers to evidence-based practice (EBP) in sport science in the United States of America (USA). A survey (28 items) was completed by 67 full-time staff who were a physical performance team member employed by universities or professional sporting organizations in the USA. Questions included the use of research, contribution of research areas, barriers to accessing and implementing EBP, and methods of feedback to the coach and players. All respondents (100%) stated they used research evidence in their performance/training program, ranking research as contributing most (largest contribution = 1 to smallest contribution = 4) to individualized preparation or recovery recommendations (1.98 ± 1.02). The top 3 preferred sources of information were "peer-reviewed research" (100% of respondents), "conferences/seminars" (76%), and "practitioners within your sport" (63%). Commonly reported perceived barriers between accessing and implementing research were "lack of staff" (accessing = 33%, implementing = 46%) "time" (accessing = 38%, implementing = 48%) and nonapplicable research (accessing = 33%, implementing = 37%), whereas "poor player compliance" was a clear barrier to implementing EBP (56%). Practitioners most preferred, and actual, method of feedback for coaching staff (87% for both) and players (94 and 95%, respectively) was "informal conversations/speaking." Improved access to educational and financial resources, increased integration of staff in coach settings and understanding of player/coach contexts may help to alleviate barriers to EBP.

Laurson, KR, Saint-Maurice, PF, Welk, GJ, and Eisenmann, JC. Reference curves for field tests of musculoskeletal fitness in U.S. children and adolescents: The 2012 NHANES National Youth Fitness Survey. J Strength Cond Res 31(8): 2075-2082, 2017-The purpose of the study was to describe current levels of musculoskeletal fitness (MSF) in U.S. youth by creating nationally representative age-specific and sex-specific growth curves for handgrip strength (including relative and allometrically scaled handgrip), modified pull-ups, and the plank test. Participants in the National Youth Fitness Survey (n = 1,453) were tested on MSF, aerobic capacity (via submaximal treadmill test), and body composition (body mass index [BMI], waist circumference, and skinfolds). Using LMS regression, age-specific and sex-specific smoothed percentile curves of MSF were created and existing percentiles were used to assign age-specific and sex-specific z-scores for aerobic capacity and body composition. Correlation matrices were created to assess the relationships between z-scores on MSF, aerobic capacity, and body composition. At younger ages (3-10 years), boys scored higher than girls for handgrip strength and modified pull-ups, but not for the plank. By ages 13-15, differences between the boys and girls curves were more pronounced, with boys scoring higher on all tests. Correlations between tests of MSF and aerobic capacity were positive and low-to-moderate in strength. Correlations between tests of MSF and body composition were negative, excluding absolute handgrip strength, which was inversely related to other MSF tests and aerobic capacity but positively associated with body composition. The growth curves herein can be used as normative reference values or a starting point for creating health-related criterion reference standards for these tests. Comparisons with prior national surveys of physical fitness indicate that some components of MSF have likely decreased in the United States over time.

The Family Nutrition and Physical Activity Screening Tool (FNPA) evaluates family behavioural and environmental factors associated with pediatric obesity, but it is unknown if FNPA scores differ among youth across obesity severities. Our aim was to determine the association between the FNPA and obesity severity in youth referred to weight management.Upon initiating treatment, height, weight, and the FNPA were collected according to standard procedures. Cut-points for overweight/obesity, severe obesity (SO) class 2, and SO class 3 were calculated. FNPA scores were compared across weight status groups using analysis of covariance, and odds of SO across FNPA quartiles were evaluated with multiple logistic regression.Participants included 564 5-18year old who initiated treatment and completed the FNPA. After adjustment, FNPA scores differed by weight status with higher/healthier scores in youth with overweight/obesity (56.6±8.5) when compared to those with SO class 2 (55.0±7.1; p=0.015) or SO class 3 (53.6±9.0; p0.001). Compared to those in the highest FNPA quartile, youth in the 2nd quartile had 1.8 (95% CI: 1.1, 2.9) times higher odds of SO, and those in the lowest FNPA quartile had 2.1 (95% CI: 1.3, 3.4) times higher odds of SO. Youth with SO had unhealthier subscale scores among 6 of 10 constructs, including nutritional, physical activity, sedentary, and sleep behaviours.Results suggest a consistent inverse relationship between the FNPA and adiposity among youth presenting for weight management. The FNPA is a useful metric for programs and clinicians targeting family behaviours and the home environment to combat obesity.

This article was published in Strength & Conditioning Journal on 01 April 2017 available at http://dx.doi.org/10.1519/SSC.0000000000000281

Objective This study examined trajectories of trunk fat mass (FM) accrual during emerging adulthood of individuals categorized, at 36 years of age, as having higher compared with lower scores of (1) metabolic risk and (2) blood pressure risk. Methods Fifty-five individuals from the Saskatchewan Pediatric Bone Mineral Accrual Study (1991-2017) were assessed from adolescence (mean [SD], 11.5 [1.8] years) through emerging adulthood (26.2 [2.2] years) and into early adulthood (35.6 [2.2] years) (median 11 visits per individual). Sex-specific median splits of continuous standardized risk scores at 36 years of age were created. Dual-energy x-ray absorptiometry-assessed trunk FM trajectories were analyzed using multilevel random effects models. Results Higher risk scores of blood pressure risk and metabolic risk had significantly steeper trajectories of fat development (0.45 [0.11] and 0.44 [0.11] log g, respectively) than the lower risk scores. Dietary fat was not related (P > 0.05). Physical activity was negatively related (-0.04 [0.02] physical activity score) to trunk FM development during emerging adulthood. Conclusions Young adults with higher metabolic risk at 36 years of age had greater trunk FM development during both adolescence and emerging adulthood, supporting the need for intervention at both these critical periods of fat accrual.

Studies concerning child and adolescent growth, development, performance and health aimed at the multiple interactions amongst this complex set of variables are not common in the Portuguese speaking countries.The aim of this paper is to address the key ideas, methodology and design of the Oporto Growth, Health and Performance Study (OGHPS).The OGHPS is a multidisciplinary mixed-longitudinal study whose main purpose is to examine the multiple interactions among biological, environmental and lifestyle indicators that affect growth, development, health and performance of Portuguese adolescents aged 10-18 years old.This study briefly presents baseline results for growth, physical fitness and lifestyle behaviours for those participating in the cross-sectional sample (n ≈ 8000). Approximately 30% were over-fat or obese. On average, boys were more physically fit and active than girls. Few adolescents meet the guidelines for sleep duration (≈10%) and eating habits (16.2-24.8%), while 76-85% meet the recommended levels of moderate-to-vigorous physical activity.The OGHPS has an innovative approach due to its mixed-longitudinal design and the broad array of variables. Furthermore, subsequent analyses of the longitudinal data will enable a detailed exploration of important factors affecting the growth trajectories of health and performance variables and will also help to identify some of the most opportune times for interventions in terms of health behaviours.

In this paper, three different statistical approaches were used to investigate short-term tracking of cardiorespiratory and performance-related physical fitness among adolescents. Data were obtained from the Oporto Growth, Health and Performance Study and comprised 1203 adolescents (549 girls) divided into two age cohorts (10–12 and 12–14 years) followed for three consecutive years, with annual assessment. Cardiorespiratory fitness was assessed with 1-mile run/walk test; 50-yard dash, standing long jump, handgrip, and shuttle run test were used to rate performance-related physical fitness. Tracking was expressed in three different ways: auto-correlations, multilevel modelling with crude and adjusted model (for biological maturation, body mass index, and physical activity), and Cohen’s Kappa (κ) computed in IBM SPSS 20.0, HLM 7.01 and Longitudinal Data Analysis software, respectively. Tracking of physical fitness components was (1) moderate-to-high when described by auto-correlations; (2) low-to-mo...

In this article, we describe a protocol used to test the functional capacity of the obese pediatric patient and describe the peak oxygen consumption (VO2peak) of patients seeking treatment at a pediatric weight management center.One hundred eleven (mean age, 12.5 ± 3.0 years) patients performed a multistage exercise test on a treadmill, of which 90 (81%) met end-test criteria and provided valid VO2peak data. Peak VO2 was expressed: (1) in absolute terms (L·min(-1)); (2) as the ratio of the volume of oxygen consumed per minute relative to total body mass (mL·kg(-1)·min(-1)); and (3) as the ratio of the volume of oxygen consumed per minute relative to fat-free mass (mL·FFM·kg(-1)·min(-1)).Mean BMI z-score was 2.4 ± 0.3 and the mean percent body fat was 36.5 ± 9.7%. Absolute VO2peak (L·min(-1)) was significantly different between sexes; however, relative values were similar between sexes. Mean VO2peak was 25.7 ± 4.8 mL·kg(-1)·min(-1) with a range of 13.5-36.7 mL·kg(-1)·min(-1).Obese youth seeking treatment at a stage 3 pediatric weight management center exhibit low VO2peak. The protocol outlined here should serve as a model for similar programs interested in the submaximal and peak responses to exercise in obese pediatric patients.

Purpose: The objective of this study was to examine the independent and combined association of physical activity and body mass index (BMI) with blood pressure in youth. Methods: Youth aged 8–18 years from the 2003–2006 National Health and Nutrition Examination Survey (NHANES) with BMI, blood pressure, and physical activity (accelerometer) were included in the analyses. A total of 2585 subjects (1303 males; 47% of all 8- to 18-year-olds) met these criteria. Results: Obese youth had a systolic blood pressure that was 8 mm Hg higher than normal weight youth. A significant interaction between BMI and physical activity on blood pressure was found (P Conclusions: This study showed a significant independent and combined association of BMI and physical activity with blood pressure in youth. Interventions need to focus on the reduction of fatness/BMI as a way to reduce the cardiovascular risk in youth.

OBJECTIVES This study aimed to: (1) model changes in the hypertensive and waist phenotype (HWP) in youth, and (2) investigate the effects of sex, biological maturation, total physical activity (TPA), and physical fitness (PF) in HWP trajectories. METHODS Data were obtained annually for 3 years from the Oporto Growth, Health, and Performance Study, and comprised 5,549 adolescents (2,732 girls) divided into four age cohorts (10, 12, 14, and 16 years). The HWP was computed as the sum of the standardized score of waist circumference and mean arterial pressure. Biological maturation was indirectly assessed by the maturity offset procedure; TPA was estimated with the Baecke questionnaire; PF measures included 1-mile run/walk, 50-yard dash (50YD), standing long jump (SLJ), handgrip strength (HGr), and agility shuttle run. Longitudinal changes in HWP were analyzed using multilevel modelling. RESULTS HWP increased across time with a nonlinear trend in girls and boys. However, when adjusted for a set of predictors, the trend was reversed: girls and boys had a significant annual decrease on HWP of -0.202 ± 0.032 and -0.147 ± 0.032, respectively. Maturity offset was positively associated with HWP changes (β = 0.913 ± 0.023); TPA had a negative association (β = -0.027 ± 0.011); and improved PF tests were associated with a significant reduction in HWP across time (β1mile = -0.081 ± 0.009; βSLJ = -0.003 ± 0.00; β50YD =0.106 ± 0.020; and βHGr = -3.335 ± 0.196). CONCLUSIONS Boys showed higher HWP values compared to girls from 10 to 18 years of age. Adolescents who were more biologically mature had a more adverse HWP. Longitudinal increases in TPA and PF predicted annual decreases in HWP across the adolescence years.Am. J. Hum. Biol. 28:387-393, 2016. © 2015 Wiley Periodicals, Inc.

Background:Physical activity (PA), television time (TV), and sleep duration (SLP) are considered individual risk factors for adolescent obesity. Our aim was to investigate the concurrent influence of meeting PA, SLP, and TV recommendations on adolescent obesity utilizing 2011 Youth Risk Behavior Surveillance Survey (YRBSS) data.Methods:Subjects included 9589 (4874 females) high school students. PA, SLP, and TV were categorized utilizing established national recommendations and youth were cross-tabulated into 1 of 8 groups based on meeting or not meeting each recommendation. Logistic models were used to examine the odds of obesity for each group. Results: Youth meeting the PA recommendation were not at increased odds of obesity, regardless of SLP or TV status. However, not meeting any single recommendation, in general, led to increased odds of not meeting the other two. In boys, 11.8% met all recommendations while 14.1% met 0 recommendations. In girls, only 5.0% met all recommendations while 17.8% met none.Conclusions:Boys and girls not meeting any of the recommendations were 4.0 and 3.8 times more likely to be obese compared with their respective referent groups. Further research considering the simultaneous influence these risk factors may have on obesity and on one another is warranted.

Background:The purpose of this study was to provide a practical demonstration of the impact of monitoring frame and metric when assessing pedometer-determined physical activity (PA) in youth.Methods:Children (N = 1111) were asked to wear pedometers over a 7-day period during which time worn and steps were recorded each day. Varying data-exclusion criteria were used to demonstrate changes in estimates of PA. Steps were expressed using several metrics and criteria, and construct validity was demonstrated via correlations with adiposity.Results:Meaningful fluctuations in average steps per day and percentage meeting PA recommendations were apparent when different criteria were used. Children who wore the pedometer longer appeared more active, with each minute the pedometer was worn each day accounting for an approximate increase of 11 and 8 steps for boys and girls, respectively (P < .05). Using more restrictive exclusion criteria led to stronger correlations between indices of steps per day, steps per minute, steps per leg length, steps per minute per leg length, and obesity.Conclusion:Wear time has a meaningful impact on estimates of PA. This should be considered when determining exclusion criteria and making comparisons between studies. Results also suggest that incorporating wear time per day and leg length into the metric may increase validity of PA estimates.

Objective The prevalence of metabolic syndrome in youth varies on the basis of the classification system used, prompting implementation of continuous scores; however, the use of these scores is limited to the sample from which they were derived. We sought to describe the derivation of the continuous metabolic syndrome score using nationally representative reference values in a sample of obese adolescents and a national sample obtained from National Health and Nutrition Examination Survey (NHANES) 2011–2012. Methods Clinical data were collected from 50 adolescents seeking obesity treatment at a stage 3 weight management center. A second analysis relied on data from adolescents included in NHANES 2011–2012, performed for illustrative purposes. The continuous metabolic syndrome score was calculated by regressing individual values onto nationally representative age- and sex-specific standards (NHANES III). Resultant z scores were summed to create a total score. Results The final sample included 42 obese adolescents (15 male and 35 female subjects; mean age, 14.8 ± 1.9 years) and an additional 445 participants from NHANES 2011–2012. Among the clinical sample, the mean continuous metabolic syndrome score was 4.16 ± 4.30, while the NHANES sample mean was quite a bit lower, at −0.24 ± 2.8. Conclusions We provide a method to calculate the continuous metabolic syndrome by comparing individual risk factor values to age- and sex-specific percentiles from a nationally representative sample.

Individual differences in the growth and maturation have been shown to impact player performance and development in the context of youth soccer. This study investigated Premier League academy players’ experiences of participating in a tournament bio-banded for biological maturation. Academy players (N=66) from four professional soccer clubs between 11 and 14 years of age and between 85-90% of adult stature participated in a tournament. Players competed in three 11 vs 11 games on a full size pitch with 25-minute halves. Sixteen players participated in four 15-minute focus groups and were asked to describe their experiences of participating in the bio-banded tournament in comparison to age group competition. Age groups in the UK are based upon where a player’s birth date falls in relation to the cut of dates for the school year (September 1st to August 31st). All players described their experience as positive and recommended the Premier League integrate bio-banding into the existing games programme. In comparison to age-group competitions, early maturing players described the bio-banded games more physically challenging, and found that they had to adapt their style of play placing a greater emphasis on technique and tactics. Late maturing players considered the games to be less physically challenging, yet appreciated the having more opportunity to use, develop and demonstrate their technical, physical, and psychological competencies. Bio-banding strategies appear to contribute positively towards the holistic development of young soccer players.

Purpose. The aim of this study was to investigate whether adolescent growth trajectories of aerobic fitness and adiposity were associated with mid-adulthood cardiometabolic risk (CMR).Methods. Participants were drawn from the Saskatchewan Growth and Development Study (1963–1973). Adolescent growth trajectories for maximal aerobic capacity (absolute VO2(AbsVO2)), skinfolds (SF), representing total body (Sum6SF) and central adiposity (TrunkSF), and body mass index (BMI) were determined from 7 to 17 years of age. In mid-adulthood (40 to 50 years of age), 61 individuals (23 females) returned for follow-ups. A CMR score was calculated to group participants as displaying either high or a low CMR. Multilevel hierarchical models were constructed, comparing the adolescent growth trajectories of AbsVO2,Sum6SF, TrunkSF, and BMI between CMR groupings.Results. There were no significant differences in the adolescent development of AbsVO2,Sum6SF, TrunkSF, and BMI between adult CMR groupings (p>0.05). Individuals with high CMR accrued 62% greater adjusted total body fat percentage from adolescence to adulthood (p=0.03).Conclusions. Growth trajectories of adolescent aerobic fitness and adiposity do not appear to be associated with mid-adulthood CMR. Individuals should be encouraged to participate in behaviours that promote healthy aerobic fitness and adiposity levels throughout life to reduce lifelong CMR.

In children, levels of play, physical activity, and fitness are key indicators of health and disease and closely tied to optimal growth and development. Cardiopulmonary exercise testing (CPET) provides clinicians with biomarkers of disease and effectiveness of therapy, and researchers with novel insights into fundamental biological mechanisms reflecting an integrated physiological response that is hidden when the child is at rest. Yet the growth of clinical trials utilizing CPET in pediatrics remains stunted despite the current emphasis on preventative medicine and the growing recognition that therapies used in children should be clinically tested in children. There exists a translational gap between basic discovery and clinical application in this essential component of child health. To address this gap, the NIH provided funding through the Clinical and Translational Science Award (CTSA) program to convene a panel of experts. This report summarizes our major findings and outlines next steps necessary to enhance child health exercise medicine translational research. We present specific plans to bolster data interoperability, improve child health CPET reference values, stimulate formal training in exercise medicine for child health care professionals, and outline innovative approaches through which exercise medicine can become more accessible and advance therapeutics across the broad spectrum of child health.

Background:The role of psychosocial stress in the development of obesity and metabolic syndrome is receiving increased attention and has led to examination of whether physical activity may moderate the stress-metabolic syndrome relationship. The current study examined relationships among physical activity, stress, and metabolic syndrome in adolescents.Methods:Participants (N = 126; 57 girls, 69 boys) were assessed for anthropometry, psychosocial stress, physical activity, and metabolic syndrome variables; t tests were used to examine sex differences, and regression analysis was used to assess relationships among variables controlling for sex and maturity status.Results:Mean body mass index approached the 75th percentile for both sexes. Typical sex differences were observed for systolic blood pressure, time spent in moderate and vigorous physical activity, and perceived stress. Although stress was not associated with MetS (β = –.001, P = .82), a modest, positive relationship was observed with BMI (β = .20, P = .04).Conclusions:Strong relationships between physical activity and stress with MetS or BMI were not found in this sample. Results may be partially explained by overall good physical health status of the participants. Additional research in groups exhibiting varying degrees of health is needed.

OBJECTIVE: To examine the independent and combined association of self-efficacy and fatness with physical activity in 5(th) grade children. METHODS: Participants were 281 students (10.4 ± 0.7 years). Physical activity was assessed using a self-report question. Self-efficacy to be physically active was assessed using a 5-point scale. Body fatness was assessed by bioelectrical impedance. Descriptive statistics, ANOVA, and t-tests were used. RESULTS: There were no differences in reported days of physical activity between boys and girls, and normal-fat and over-fat children. However, children with high self-efficacy participated in significantly more physical activity compared to their low self-efficacy counterparts (3.4 ± 2.0 days vs. 5.4 ± 1.8 days, respectively, p < .001). CONCLUSIONS: Only physical activity self-efficacy was related to physical activity, fatness was not.

Several studies have examined energy expenditure in various sports but there is a lack of research on the contribution of exercise and habitual activity during different training periods. This study examined changes in total daily energy expenditure (TDEE) and its components during high- and low-volume training periods. Further, changes in time spent in sedentary, light, moderate and vigorous activity in response to different training volumes were explored. Energy expenditure was measured in 15 male endurance athletes during 2 non-consecutive weeks - 1 week of high volume (>13 hours) training and another week of low volume (

Background:The purpose of this study was to determine the independent and joint association of weight status and physical activity on resting blood pressure and C-reactive protein in children.Methods:Participants were 174 (71 males, 103 females) children (mean age = 10.5 ± 0.4 yrs). Physical activity was self-reported, body mass index was calculated from measured height and body mass, and blood pressure was measured according to standard procedures. A subset of 91 children had C-reactive protein measured by fingerstick blood sample. Four weight/physical activity groups were created by cross tabulation of weight status classification and physical activity level.Results:The prevalence of low physical activity (< 5 days/wk moderate-vigorous activity) did not differ between overweight and normal weight children (50%). Physical activity was not correlated with C-reactive protein (r = 0.01; P = 0.91) and C-reactive protein was not significantly different between physical activity groups (P = 0.87). Physical activity did not modify the difference in blood pressure or C-reactive protein within weight categories.Conclusions:Fatness (specifically overweight and obesity), but not physical activity, was shown to be associated with blood pressure and C-reactive protein levels in children. Physical activity did not attenuate blood pressure or C-reactive protein in overweight and obese children.

The increasing prevalence of childhood overweight and obesity has been associated with an increased risk for cardiovascular disease (CVD). While several studies examined the effect of single behaviors such as physical activity (PA), sedentary behavior or diet on CVD risk, there is a lack of research on combined associations, specifically in children. Therefore, the purpose of this study was to examine the joint association of PA or screen time (ST) and diet on CVD risk factors in children. PA, STand diet were assessed via questionnaire in 210 fifth grade students (age: 10.6 ± 0.4 years). The healthy eating index (HEI) was subsequently calculated as indicator for diet quality. Height, weight, % body fat, and resting blood pressure were measured according to standard procedures and blood samples obtained via fingerprick were assayed for blood lipids. Total cholesterol HDL ratio (TC:HDL), mean arterial pressure (MAP), and % body fat were used as indicators of CVD risk. 55% of children did not meet current PA recommendations on at least 5 days/week and 70% exceeded current recommendations for ST. Further, only 2.5% possessed a "good" diet (HEI80). There was no significant association of PA or STand diet on CVD risk score. Neither TC:HDL, MAP, and % body fat nor the total CVD risk score was significantly correlated with diet, PA, or ST. Children in the high PA group, however, had significantly better diet scores. Despite the fact that self-reported PA, ST, or dietary intake were not directly related to CVD risk in this sample, higher activity levels were associated with a healthier diet and lower ST indicating an overall healthier lifestyle of this subgroup.

We examined the associations among daily cortisol, physical activity (MVPA) and continuous metabolic syndrome score (cMetS) in obese youth.: Fifty adolescents (mean age 14.8±1.9 years) were recruited from medical clinics. Daily MVPA (min/day) was assessed by accelerometry. Saliva was sampled at prescribed times: immediately upon waking; 30 min after waking; and 3, 6 and 9 h after waking. Fasting lipids, glucose, waist circumference and blood pressure were used to calculate a continuous metabolic syndrome score (cMetS). Multiple linear regression analysis was used to examine associations among variables.: The mean cMetS score was 4.16±4.30 and did not differ by clinic or sex. No significant relationship was found between cortisol area under the curve (cAUC) and cMetS, nor did the interaction of MVPA with cAUC significantly predict cMetS.: Physical activity, cortisol, and metabolic risk were not associated in this sample of obese adolescents. Future research should examine the role of insulin sensitivity in these relationships.

ObjectiveCardiorespiratory fitness is known to be cardioprotective and its association with the components of the metabolic syndrome in children is becoming clearer. The aim of the present study was to examine the extent to which cardiorespiratory fitness may offset the weight-related association with mean arterial pressure (MAP) in schoolchildren.DesignCross-sectional study.SettingsSchoolchildren from the East of England, UK.SubjectsA total of 5983 (48 % females) schoolchildren, 10 to 16 years of age, had height, weight and blood pressure measured by standard procedures and cardiorespiratory fitness assessed by the 20 m shuttle-run test. Participants were classified as fit or unfit using internationally accepted fitness cut-off points; and as normal weight, overweight or obese based on BMI, again using international cut-off points. Age-adjusted ANCOVA was used to determine the main effects and interaction of fitness and BMI on MAP Z-score. Logistic regression models were used to estimate odds ratios of elevated MAP.ResultsPrevalence of elevated MAP in schoolchildren was 14·8 % overall and 35·7 % in those who were obese-unfit. Approximately 21 % of participants were overweight and 5 % obese, while 23 % were classified as unfit. MAP generally increased across BMI categories and was higher in the aerobically unfit participants. Obese-fit males had lower MAP compared with obese-unfit males (P < 0·001); this trend was similar in females (P = 0·05).ConclusionsIncreasing fitness level may have a positive impact on the weight-related elevations of MAP seen in obese and overweight schoolchildren.

Except for North America and Europe, few studies have reported the association among physical activity (PA), cardiorespiratory fitness (CRF) and metabolic syndrome (MetS) in youths, especially for rural African youth.The aims of this study were to determine the prevalence of PA levels, CRF, MetS and its indicators, and examine the association between these variables in a school-aged sample of youth from rural Mozambique.The sample included 209 children and adolescents aged 7-15 years old from Calanga, a rural community in Mozambique. PA was estimated with a culturally-specific questionnaire. CRF was determined by 1-mile run test. Indicators of the MetS included fasting glucose, triglycerides, total cholesterol, blood pressure and body mass index. A continuous metabolic risk score was computed.Results showed high levels of PA and CRF and a low prevalence of MetS (2%) among children and adolescents from Calanga. However, there was a moderately high prevalence of elevated blood pressure (81.8%) and triglycerides (18.7%), respectively. There were no significant associations between PA, CRF and MetS.Youths from Calanga are physically active and possess high CRF and their lifestyle may be a protective effect against MetS.

Background: Both reduced moderate-to-vigorous physical activity (MVPA) and increased screen time have been implicated in the aetiology of childhood overweight/obesity. This study aimed to determine which behaviour had the stronger association with overweight/obesity. Method: 2200 randomly selected 9- to 16-year-old Australians provided four 24-h use-of-time recalls. Participants were classified into weight status categories and as high or low physical active, and high or low screen time according to Australian guidelines (≥60 min MVPA; ≤120 min recreational screen time daily). Multivariate logistic regression was used to calculate the odds ratios (OR) for overweight/obesity for each screen time and MVPA category. Results: Increased likelihood of overweight or obese was often associated with high screen time (ORs, 2.13–2.55 for boys and 1.47–1.72 for girls), but only sometimes and less strongly associated with low MVPA (ORs, 0.49–2.55 for boys and 1.06–1.47 for girls). Analyses conducted for combined screen time and MVPA categories showed screen time to be a stronger indicator of weight status than physical activity, especially in boys. Conclusion: Overweight and obesity were more strongly associated with screen time than physical activity. Screen time may be an important target for interventions aimed at reducing childhood overweight and obesity.

The primary purpose of this study was to examine dietary intake in endurance-trained athletes during a week of high-volume and a week of low-volume training while measuring exercise energy expenditure (EEE), resting metabolic rate (RMR), and nonexercise activity thermogenesis (NEAT). In addition, compliance with current American College of Sports Medicine/American Dietetic Association nutrition and performance recommendations for macronutrients was evaluated. Energy expenditure and dietary intake were measured in 15 male endurance athletes during 2 nonconsecutive weeks resembling a high-volume and a low-volume training period. Anthropometric measurements were taken and percentage body fat was determined at the beginning and end of each week of training. Total daily energy expenditure (TDEE) was calculated by summing RMR, NEAT, and EEE. Dietary intake was assessed with an online food-frequency questionnaire completed at the end of each week of data collection. Despite significant differences between TDEE and energy intake, no difference in body composition between the beginning and end of either week of training was observed, suggesting underreporting of caloric intake. Further, no changes in total caloric intake or macronutrient intake occurred even though TDEE increased significantly during the high-volume training. Reported carbohydrate intake (4.5 g·kg(-1)) and fiber intake (25 g·day(-1)) were below recommendations, whereas fat intake (1.3 g·kg(-1)) was slightly above recommendations. In summary, no short-term dietary adjustments occurred in response to differences in training regimen. Because these athletes were generally consuming a Western diet, they may have required some support to achieve desirable intakes for health and performance.

There is growing concern regarding the influence of media exposure on American children's health and development. The current prospective study tested the direct relations between media exposure, sleep, and various health outcomes (e.g. attention problems, aggression, and body composition) and the indirect effect of media exposure through sleep disturbances. Child participants (N = 1,317) completed measures of media consumption and sleep. Teachers reported on children's attention problems and use of physical aggression. Results showed that media exposure at Time 1 was indirectly related to attention, physical aggression, and Body Mass Index at Time 3 (13 months later), mediated by sleep at Time 2. Overall, these results support the hypothesis that screen time is negatively related to health outcomes, and that displaced sleep is one of the mediating mechanisms underlying these relations.

Background There is no consensus as to whether low dietary intakes of saturated fat or cholesterol, or high intakes of dietary fiber are related to a lower prevalence of metabolic syndrome (MetS) in adolescent children. Objective To determine whether a fiber-rich diet as measured by a fiber index (grams fiber/1,000 kcal) is associated with lower rates of MetS among adolescents vs a diet low in saturated fat or cholesterol as measured by a saturated fat index (grams saturated fat/1,000 kcal) and a cholesterol index (milligrams cholesterol/1,000 kcal), respectively. Design/participants/setting Cross-sectional analysis of 12- to 19-year-old boys and girls (N=2,128) who participated in the National Health and Nutrition Examination Survey 1999-2002. Outcomes and statistical analyses The prevalence of MetS (abnormal values of three or more of the following: waist circumference, blood pressure, fasting serum high-density lipoprotein cholesterol, triglycerides, and glucose) was compared across quintiles of the dietary indexes (fiber index, saturated fat index, and cholesterol index) derived from 24-hour recalls. χ 2 tests determined the prevalence across dietary quintiles, and multivariate logistic regression evaluated the association of the dietary indexes with MetS. Weighted analyses were used controlling for sex, age, ethnicity, and family income. Significance was set at P ≤0.05. Results The overall prevalence of MetS was 6.4% (n=138). There was a graded inverse association between the fiber index and MetS ( P P ≤0.043). Neither the saturated fat index ( P =0.87) nor the cholesterol index ( P =0.22) was significantly associated with MetS. Conclusions Higher intakes of dietary fiber, but not low intakes of saturated fat or cholesterol are related to the MetS in adolescents. These findings suggest that to reduce the risks for MetS in adolescents, it is more important to emphasize a paradigm that promotes the inclusion of fiber-rich, nutrient-dense, plant-based foods vs what foods to restrict or exclude as is commonly done when the focus is on total fat, cholesterol, or saturated fat intake.

Background: Multiple screening tools, such as BMI and skinfold-derived percent body fat (%BF), are available to identify youth at risk of excess adiposity. However, poor classification agreement among these tools can be problematic for those interpreting test results. Purpose: The purpose of this study was to investigate the validity of using BMI as an estimate of %BF in youth and to identify optimal BMI thresholds for identifying at-risk children and adolescents based on %BF. Methods: Percent body fat was derived from the skinfold thicknesses of children aged 5-18 years from three cross-sectional waves of the National Health and Nutrition Examination Survey (NHANES (1999 -2004); N8269). Stature and body mass from the same data set were used to calculate BMI. Receiver operating characteristic (ROC) analysis was employed to determine the optimal BMI thresholds for detecting previously created %BF standards. Results: The optimal BMI percentile associated with the low risk %BF threshold was the 83rd and 80th in boys and girls, respectively. The selected BMI percentiles associated with the higher risk threshold were the 92nd and 90th in boys and girls, respectively. Overall, classification accuracy when using BMI percentiles to identify the two %BF risk groups ranged from 86.9% to 89.1%. Conclusions: BMI and skinfold-derived %BF demonstrate reasonable agreement when used to classify adiposity status in children and adolescents. (Am J Prev Med 2011;41(4S2):S100 -S105) © 2011 American Journal of Preventive Medicine

Background: Few studies have identified health-related criterion standards of percent body fat (%BF) in U.S. youth. Further, existing standards are static thresholds (e.g., 25%, 30%) and do not account for normal growth and maturation. Purpose: The purpose of this study was to identify thresholds of %BF in youth linked to metabolic syndrome in a large sample of U.S. children and adolescents. Methods: Percent fat was derived from the skinfold thicknesses of those aged 12-18 years, from the National Health and Nutrition Examination Survey (NHANES (1999 -2004, N1966)). Metabolic syndrome was classified using previously published standards based on the National Cholesterol Education Program/Adult Treatment Panel III adult values at age 20 years. Using %BF z-scores as the test and metabolic syndrome as the criterion, receiver operating characteristic (ROC) curve analysis was used to identify %BF thresholds. Results: ROC analysis indicated that %BF can be used with moderate accuracy to identify metabolic syndrome in adolescents. %BF thresholds of 22.3% and 35.1% in boys and 31.4% and 38.6% in girls (at age 18 years) were found to be indicative of "low" and "high" metabolic syndrome risk. Conclusions: Age- and gender-specific %BF thresholds for creating separate risk groups were identified in relation to metabolic syndrome status. The selected thresholds identify adolescents with unfavorable metabolic profiles. These values could be extrapolated to younger children using previ- ously created %BF centiles, which potentially allows for earlier identification and intervention of at-risk youth if tracking of current %BF was maintained. (Am J Prev Med 2011;41(4S2):S93-S99) © 2011 American Journal of Preventive Medicine

Background To date, several studies have been published outlining reference percentiles for BMI in children and adolescents. In contrast, there are limited reference data on percent body fat (%BF) in U.S. youth. Purpose The purpose of this study was to derive smoothed percentile curves for %BF in a nationally representative sample of U.S. children and adolescents. Methods Percent fat was derived from the skinfold thicknesses of those aged 5–18 years from three cross-sectional waves of the National Health and Nutrition Examination Survey (NHANES) IV (1999–2000, 2001–2002, and 2003–2004; N=8269). The LMS (L=skewness, M=median, and S=coefficient of variation) regression method was used to create age- and gender-specific smoothed percentile curves of %BF. Results Growth curves are similar between boys and girls until age 9 years. However, whereas %BF peaks for boys at about age 11 years, it continues to increase for girls throughout adolescence. Median %BF at age 18 years is 17.0% and 27.8% for boys and girls, respectively. Conclusions Growth charts and LMS values based on a nationally representative sample of U.S. children and adolescents are provided so that future research can identify appropriate cut-off values based on health-related outcomes. These percentiles are based on skinfolds, which are widely available and commonly used. Using %BF instead of BMI may offer additional information in epidemiologic research, fitness assessment, and clinical settings.

This article provides descriptive information on the assessments conducted in stage 3 or 4 pediatric obesity-management programs associated with National Association of Children's Hospital and Related Institutions hospitals enrolled in FOCUS on a Fitter Future. Eighteen institutions completed a survey that considered the following assessments: patient/family medical history; physical examination; blood pressure; body size and composition; blood chemistry; aerobic fitness; resting metabolic rate; muscle strength and flexibility; gross motor function; spirometry; sedentary behavior and physical activity; dietary behavior and nutrition; and psychological assessments. Frequency distributions were determined for each question. Overall, the results indicate that most programs that participated in this survey were following 2007 Expert Committee assessment recommendations; however, a variety of measurement tools were used. The variation in assessment tools, protocols, etc is partially caused by the program diversity dictated by personnel, both in terms of number and duties. It also shows the challenges in standardizing methodologies across clinics if we hope to establish a national registry for pediatric obesity clinics. In addition to providing a better understanding of the current assessment practices in pediatric obesity-management programs, the results provided herein should assist other clinics/hospitals that are developing pediatric obesity programs.

To examine the association of the Family Nutrition and Physical Activity (FNPA) screening tool with cardiovascular disease (CVD) risk factors in 10-year old children.A total of 119 children were assessed for body mass index (BMI), percent body fat, waist circumference, total cholesterol, high-density lipoprotein-cholesterol (HDL), and resting blood pressure. A continuous CVD risk score was created using total cholesterol to HDL-cholesterol ratio (TC:HDL), mean arterial pressure (MAP), and waist circumference. The FNPA survey was completed by parents.The FNPA score was significantly correlated with adiposity measures (r = ?0.35 to ?0.43) and the continuous CVD risk score (r = ?0.22) (p0.05) but not with TC:HDL or MAP. The prevalence of overweight and obese (43.1% vs. 14.9%) and the mean values for BMI (20.3 ? 4.3 vs. 18.0 ? 2.7 kg/m(2)) and percent body fat (24.8 ? 8.3% vs. 20.1 ? 5.7%) were significantly higher in children with a FNPA score ? 25 when compared to those with a FNPA score25 (median split) (p0.05). The continuous CVD risk score was not significantly different between these two groups. Overweight and obese children had a significantly lower mean FNPA score when compared to normal weight children.Children from a high-risk, obesogenic family environment (determined using the FNPA) have a higher level of adiposity and CVD risk factor profile than children from a low-risk family environment. The FNPA screening tool can help identify children that may be at risk for overweight and adverse CVD risk factor development.

Previous ice hockey research has focused on physiological profiles and determinants of skating speed, but few studies have examined the association of preseason player evaluations with a measure of season-long performance. Understanding which tests are most predictive of player performance could help coaches organize practice and training more effectively. The purpose of this study was to describe physical characteristics and skill levels of 24 members of an NCAA Division I men's ice hockey team and relate them to game performance over the course of a season as measured by plus/minus (+/-) score. Subjects performed a battery of preseason tests including treadmill maximal aerobic capacity, body fat, leg press, push-ups, bench press, chin-ups, and sprinting ability both on and off ice. Pearson and Spearman correlations were used to examine correlations between preseason measures and +/- score. One coach also subjectively grouped the top and bottom 6 players, and analysis of variance was used to examine any differences in preseason measures and +/- score between these 2 groups. Leg press, chin-ups, bench press, and repeat sprint performance were significantly correlated with +/- score (r = 0.554, 0.462, 0.499, and -0.568, respectively). Teams with limited time and resources may choose to perform these tests to evaluate player potential efficiently. Only +/- score differed between top and bottom players suggesting that +/- accurately reflected the coach's perception of player success in this sample.