title: The effect of dance mat exergaming systems on physical activity and health – related outcomes in secondary schools: results from a natural experiment The Physical Activity 4 Everyone Cluster Randomized Trial: 2-Year Outcomes of a School Physical Activity Intervention Among Adolescents. Intervention effects on physical activity: the HEIA study - a cluster randomized controlled trial Secular and longitudinal physical activity changes in population‐based samples of children and adolescents Effectiveness of the ‘Girls Active’ school-based physical activity programme: A cluster randomised controlled trial Quality of reporting of observational longitudinal research. Objectively measured physical activity and sedentary time: cross-sectional and prospective associations with adiposity in the Millennium Cohort Study Effect and cost of an after-school dance programme on the physical activity of 11–12 year old girls: The Bristol Girls Dance Project, a school-based cluster randomised controlled trial Assessment of a two-year school-based physical activity intervention among 7-9-year-old children ENERGY BALANCE IN ADOLESCENT GIRLS: THE TRIAL OF ACTIVITY FOR ADOLESCENT GIRLS COHORT Fatness leads to inactivity, but inactivity does not lead to fatness: a longitudinal study in children (EarlyBird 45) Cross-sectional and prospective associations between moderate to vigorous physical activity and sedentary time with adiposity in children Time spent in sedentary behavior and changes in childhood BMI: a longitudinal study from ages 9 to 15 years Physical activity and skills intervention: SCORES cluster randomized controlled trial. One-year changes in physical activity and sedentary behavior among adolescents: the Croatian Physical Activity in Adolescence Longitudinal Study (CRO-PALS). Longitudinal associations of fundamental movement skills with objectively measured physical activity and sedentariness during school transition from primary to lower secondary school. Strength exercises during physical education classes in secondary schools improve body composition: a cluster randomized controlled trial Longitudinal changes in vigorous intensity physical activity from childhood to adolescence: Gateshead Millennium Study. Developmental Trajectories of Physical Activity, Sports, and Television Viewing During Childhood to Young Adulthood: Iowa Bone Development Study.
abstract: Background Exergaming has been proposed as an innovative method for physical activity promotion . However , large effectiveness studies are rare . In January 2011 , dance mat systems  were introduced in secondary schools in two districts in Engl and with the aim of promoting an innovative opportunity for physical activity . The aim of this natural experiment was to examine the effect of introducing the dance mat exergaming systems on physical activity and health-related outcomes in 11–13 year old students using a non-r and omised controlled design and mixed methods . Methods Participants were recruited from five schools in intervention districts ( n = 280 ) and two schools in neighbouring control districts ( n = 217 ) .  Data on physical activity ( accelerometer ) , anthropometrics ( weight , BMI and percentage of body fat ) , aerobic fitness ( 20-m multistage shuttle run test ) , health-related quality of life ( Kidscreen question naire ) , self-efficacy ( children ’s physical activity self-efficacy survey ) , school attendance , focus groups with children and interviews with teachers were collected at baseline and approximately 12 months follow-up . Results There was a negative intervention effect on total physical activity ( -65.4 cpm CI : -12.6 to -4.7 ) , and light and sedentary physical activity when represented as a percentage of wear time ( Light : -2.3 % CI : -4.5 to 0.2 ; Sedentary : 3.3 % CI : 0.7 to 5.9 ) . However , compliance with accelerometers at follow-up was poor . There was a significant positive intervention effect on weight ( -1.7 kg , 95 % CI : -2.9 to -0.4 ) , BMI ( -0.9 kg/m2 , 95 % CI : -1.3 to -0.4 ) and percentage of body fat ( -2.2 % , 95 % CI : -4.2 to -0.2 ) . There was also evidence of improvement in some health-related quality of life parameters : psychological well-being ( 2.5 , 95 % CI : 0.1 to 4.8 ) and autonomy and parent relation ( 4.2 , 95 % CI : 1.4 to 7.0 ) . Conclusions The implementation of a dance mat exergaming scheme was associated with improvement in anthropometric measurements and parameters of health-related quality of life . However , the mechanisms of these benefits are unclear as there was insufficient data from physical activity to draw robust conclusions . Qualitative findings suggest that there was declining support for the initiative over time , meaning that potential benefits may not have been achieved INTRODUCTION Few interventions have been successful in reducing the physical activity decline typically observed among adolescents . The aim of this paper is to report the 24-month effectiveness of a multicomponent school-based intervention ( Physical Activity 4 Everyone ) in reducing the decline in moderate to vigorous physical activity ( MVPA ) among secondary school students in disadvantaged areas of New South Wales , Australia . STUDY DESIGN A cluster RCT was conducted in five intervention and five control schools with follow-up measures taken at 24 months post-r and omization . SETTING / PARTICIPANTS The trial was undertaken within secondary schools located in disadvantaged communities in New South Wales , Australia . INTERVENTION A multicomponent school-based intervention based on the Health Promoting Schools Framework was implemented . The intervention consisted of seven physical activity promotion strategies that targeted the curriculum ( teaching strategies to increase physical activity in physical education lessons , student physical activity plans , and modification of school sport program ) ; school environment ( recess/lunchtime activities , school physical activity policy ) ; parents ( parent newsletters ) ; and community ( community physical activity provider promotion ) . Six additional strategies supported school implementation of the physical activity intervention strategies . MAIN OUTCOME MEASURE Minutes per day spent in MVPA , objective ly measured by accelerometer . RESULTS Participants ( N=1,150 , 49 % male ) were a cohort of students aged 12 years ( Grade 7 ) at baseline ( March-June 2012 ) and 14 years ( Grade 9 ) at follow-up ( March-July 2014 ) . At 24-month follow-up , there were significant effects in favor of the intervention group for daily minutes of MVPA . The adjusted mean difference in change in daily MVPA between groups was 7.0 minutes ( 95 % CI=2.7 , 11.4 , p<0.002 ) ( analysis conducted December 2014-February 2015 ) . Sensitivity analyses based on multiple imputation were consistent with the main analysis ( 6.0 minutes , 95 % CI=0.6 , 11.3 , p<0.031 ) . CONCLUSIONS The intervention was effective in increasing adolescents ' minutes of MVPA , suggesting that implementation of the intervention by disadvantaged schools has the potential to slow the decline in physical activity . TRIAL REGISTRATION Australian New Zeal and Clinical Trials Registry ACTRN12612000382875 Background Although school-based interventions to promote physical activity in adolescents have been suggested in several recent review s , questions have been raised regarding the effects of the strategies and the methodology applied and for whom the interventions are effective . The aim of the present study was to investigate effects of a school-based intervention program : the HEalth in Adolescents ( HEIA ) study , on change in physical activity , and furthermore , to explore whether potential effects varied by gender , weight status , initial physical activity level and parental education level . Methods This was a cluster r and omized controlled 20 month intervention study which included 700 11-year-olds . Main outcome -variable was mean count per minute ( cpm ) derived from ActiGraph accelerometers ( Model 7164/GT1 M ) . Weight and height were measured objective ly . Adolescents reported their pubertal status in a question naire and parents reported their education level on the consent form . Linear mixed models were used to test intervention effects and to account for the clustering effect of sampling by school . Results The present study showed an intervention effect on overall physical activity at the level of p = 0.05 with a net effect of 50 cpm increase from baseline to post intervention in favour of the intervention group ( 95 % CI −0.4 , 100 ) . Subgroup analyses showed that the effect appeared to be more profound among girls ( Est 65 cpm , CI 5 , 124 , p = 0.03 ) and among participants in the low-activity group ( Est 92 cpm , CI 41 , 142 , p < 0.001 ) , as compared to boys and participants in the high-activity group , respectively . Furthermore , the intervention affected physical activity among the normal weight group more positively than among the overweight , and participants with parents having 13–16 years of education more positively than participants with parents having either a lower or higher number of years of education . The intervention seemed to succeed in reducing time spent sedentary among girls but not among boys . Conclusions A comprehensive but feasible , multi-component school-based intervention can affect physical activity patterns  in adolescents by increasing overall physical activity . This intervention effect seemed to be more profound in girls than boys , low-active adolescents compared to high-active adolescents , participants with normal weight compared to the overweight , and for participants with parents of middle education level as opposed to those with high and low education levels , respectively . An implementation of the HEIA intervention components in the school system may have a beneficial effect on public health by increasing overall physical activity among adolescents and possibly among girls and low-active adolescents in particular The aims of this study were to investigate whether  physical activity ( PA ) and sedentary time ( ST )  in 9- and 15-year-olds differed between 2005 - 2006 and 2011 - 2012 ( secular change ) , and to investigate changes in PA and ST from age 9 to 15 ( longitudinal change ) . In 2005 - 2006 , we invited nationally representative sample s of Norwegian 9- ( n=1470 ) and 15-year-olds ( n=1348 ) to participate . In 2011 - 2012 , we invited a new nationally representative sample of 9-year-olds ( n=1945 ) , whereas 15-year-olds ( n=1759 ) were invited to participate either based on previous participation in 2005 - 2006 or from a r and om sample of schools . We assessed PA and ST objective ly using accelerometers . In 2011 - 2012 , both 9- and 15-year-olds spent more time sedentary ( ≥35.7 min/d , P<.001 ) and less time in light PA ( ≥35.2 min/d , P<.001 ) compared to their peers in 2005 - 2006 . Nine-year-old girls also spent less time in moderate-to-vigorous PA ( MVPA ) ( 4.2 min/d , P=.041 ) . In both age groups , the proportion accumulating an average of 60 min/d of MVPA did not differ between the two cohorts . From age 9 to 15 , girls and boys decreased their time spent in LPA ( ≥106.7 min/d , P<.001 ) and in MVPA ( ≥20.8 min/d , P<.001 ) . During the same period , ST increased by a mean of > 2 h/d ( P<.011 ) . We observed an adverse secular change in PA from 2005 - 2006 to 2011 - 2012 among 9- and 15-year-olds , and a large decline in PA in the participants followed longitudinally from age 9 to 15 years Background Globally , adolescent girls ’  physical activity ( PA ) levels are low . The ‘ Girls Active ’ secondary school-based programme , developed by the Youth Sport Trust , aims to increase PA in adolescent girls . This paper explores the effectiveness of the ‘ Girls Active ’ school-based PA programme . Methods A r and om sample of girls aged 11–14 from 20 secondary schools ( Midl and s , UK ) participated in a two-arm cluster r and omised controlled trial . Ten schools received Girls Active and 10 continued with usual practice . Measurements were taken at baseline , seven- and 14-month follow-up . Primary outcome : wrist-worn accelerometer measured moderate- to vigorous-intensity PA ( MVPA ) .  Secondary outcomes : overall PA , light PA , sedentary time , body composition , and psychosocial outcomes . Generalised estimating equations , adjusted for school cluster and potential confounders , were used and A priori subgroup analysis was undertaken . Micro-costing and cost-consequence analyses were conducted using bespoke collection methods on programme delivery information . Outcomes for the cost-consequence analysis were health related quality of life measured by the Child Health Utility-9D and service use . Results Overall , 1752 pupils participated , 1211 ( 69.1 % ) provided valid 14-month accelerometer data . No difference in MVPA ( mins/day ; 95 % confidence intervals ) was found at 14 months ( 1.7 ; -0.8 to 4.3 ) , there was at seven months ( 2.4 ; 0.1 to 4.7 ) . Subgroup analyses showed significant intervention effects on 14-month in larger schools ( 3.9 ; 1.39 to 6.09 ) and in White Europeans ( 3.1 ; 0.60 to 6.02 ) and in early maturers ( 5.1 ; 1.69 to 8.48 ) at seven months . The control group did better in smaller schools at 14-months ( -4.38 ; -7.34 to -1.41 ) . Significant group differences were found in 14-month identified motivation ( -0.09 ; -0.18 to -0.01 ) and at seven months in : overall PA ( 1.39 mg/day ; 0.1 to 2.2 ) , after-school sedentary time ( -4.7 ; -8.9 to -0.6 ) , whole day ( 5.7 ; 1.0 to 10.5 ) and school day ( 4.5 ; 0.25 to 8.75 ) light PA , self-esteem . Small , statistically significant , differences in some psychosocial variables favoured control schools . Micro-costing demonstrated that delivering the programme result ed in a range of time and financial costs at each school . Cost-consequence analysis demonstrated no effect of the programme for health related quality of life or service use . Conclusions Compared with usual practice , ‘ Girls Active ’ did not affect 14-month MVPA.Trial registration IS RCT Observational longitudinal research is particularly useful for assessing etiology and prognosis and for providing evidence for clinical decision making . However , there are no structured reporting requirements for studies of this design to assist authors , editors , and readers . The authors developed and tested a checklist of criteria related to threats to the internal and external validity of observational longitudinal studies . The checklist criteria concerned recruitment , data collection , biases , and data analysis and descriptive issues relevant to study rationale , study population , and generalizability . Two raters independently assessed 49 r and omly selected articles describing stroke research published from 1999 to 2003 in six journals : American Journal of Epidemiology , Journal of Epidemiology and Community Health , Stroke , Annals of Neurology , Archives of Physical Medicine and Rehabilitation , and American Journal of Physical Medicine and Rehabilitation . On average , 17 of the 33 checklist criteria were reported . Criteria describing the study design were better reported than those related to internal validity . No relation was found between study type ( etiologic or prognostic ) or word count and quality of reporting . A flow diagram for summarizing participant flow through a study was developed . Editors and authors should consider using a checklist and flow diagram when reporting on observational longitudinal research Objective To examine whether physical activity ( PA ) and sedentary time ( ST ) in primary school-aged children are associated with adiposity at the start of secondary school , and whether these associations differ by sex or ethnic group . Design Nationally representative prospect i ve cohort study . Setting Children born across the UK , between 2000 and 2002 . Participants 6497 singleton children . Outcome measures Measures of adiposity ( body mass index ( BMI ) , fat mass index ( FMI ) and fat free mass index (FFMI))—obtained at 7 and 11 years . Explanatory measures  Total daily PA ( mean counts per minute ( cpm ) ) ; minutes of moderate-to-vigorous PA ( MVPA ) ; and ST .  All assessed at 7 years using accelerometers . Results In cross-sectional analyses , total PA was inversely associated with FMI ( 3.7 % ( 95 % CI 2.7 % to 4.7 % ) reduction per 150 cpm increase ) , as was MVPA ( 4.2 % ( CI 3.2 % to 5.2 % ) reduction per 20 min/day increase ) . Associations were stronger in black and South Asian ethnic groups . Total PA and MVPA were not associated with FFMI . ST was positively associated with FMI ( 1.3 % ( CI 0.2 % to 2.3 % ) increase per 50 min/day increase ) and inversely associated with FFMI ( 0.5 % ( CI 0.2 % to 0.7 % ) reduction per 50 min/day increase ) . Longitudinally , MVPA at age 7 years remained inversely associated with FMI at age 11 years ( 1.5 % ( CI 0.4 % to 2.6 % ) reduction per 20 min/day increase ) . No association was found between total PA and ST and any of the later adiposity measures . Conclusions 7-year-old children who are more physically active are less likely to be obese at that age and at age 11 years . These associations were particularly evident in children from black or South Asian ethnicity at age 7 years and in boys at age 11 years . Measurements of fat mass provide valuable insights into ethnic differences in associations between adiposity and activity Background The aim of this study was to examine the effectiveness and cost of an after-school dance intervention at increasing the physical activity levels of Year 7 girls ( age 11–12 ) . Methods A cluster r and omised controlled trial was conducted in 18 secondary schools . Participants were Year 7 girls attending a study school . The Bristol Girls Dance Project ( BGDP ) intervention consisted of up to forty , 75-minute dance sessions delivered in the period immediately after school by experienced dance instructors over 20-weeks . The pre-specified primary outcome was  accelerometer assessed mean minutes of weekday moderate to vigorous physical activity ( MVPA ) at time 2 ( 52 weeks are T0 baseline assessment s ) . Secondary outcomes included accelerometer assessed mean minutes of weekday MVPA at time 1 ( while the intervention was still running ) and psychosocial outcomes . Intervention costs were assessed . Results 571 girls participated . Valid accelerometer data were collected from 549 girls at baseline with 508 girls providing valid accelerometer data at baseline and time 2 . There were no differences between the intervention and control group for accelerometer assessed physical activity at either time 1 or time 2 . Only one third of the girls in the intervention arm met the pre-set adherence criteria of attending two thirds of the dance sessions that were available to them . Instrumental variable regression analyses using complier average causal effects provided no evidence of a difference between girls who attended the sessions and the control group . The average cost of the intervention was £ 73 per girl , which was reduced to £ 63 when dance instructor travel expenses were excluded . Conclusion This trial showed no evidence that an after-school dance programme can increase the physical activity of Year 7 girls . The trial highlighted the difficulty encountered in maintaining attendance in physical activity programmes delivered in secondary schools . There is a need to find new ways to help adolescent girls to be physically active via identifying ways to support and encourage sustained engagement in physical activity over the life course . Trial registration IS RCT Background  Physical activity ( PA )  in children has declined in recent decades , highlighting the need for effective intervention programs for school-aged children . The main objective of this study was to assess to what extent PA during and after school hours changed among children who received a progressive two-year long intervention vs. that of children who only received general curriculum-based PA .  Methods A cluster r and omized intervention study was conducted and six elementary schools r and omly assigned to serve as control- or intervention schools . All children attending second grade ( mean age = 7.4 years - born in 1999 ) were invited to participate in the fall of 2006 ( N = 320 , 82 % participated ) , again in 2007 ( midpoint ) and 2008 ( end of intervention ) . The intervention consisted of multi-component PA-intervention during school hours and was conducted by teachers at each intervention school . PA  was assessed by means of accelerometers and subjectively at the intervention schools via teachers ' PA log-books . Results There was no difference in PA intensity ( minutes of moderate-to-vigorous physical activity - min of MVPA ) between the two study groups at baseline , but children in the intervention schools were more physically active at moderate-to-vigorous intensity compared to those in control schools after one year of intervention ( mean difference of MVPAlog-minutes : 0.61 , 95%CI : 0.02 , 1.20 , p = 0.04 ) . Moreover , the model for minutes of MVPA during school hours , showed a significant three-way interaction between time at mid-point , group and gender ( mean difference of MVPAlog-minutes : 1.06 , 95%CI : 0.15 , 1.97 , p = .02 ) , indicating a significantly greater increase among the boys in the intervention schools compared to girls . No difference in PA was detected between the study groups at the end of the study period after two years of intervention . Conclusions The results suggest that the objective of increasing PA at school was met after one year of intervention , and it was more pronounced among boys . The lack of increase at the end of the study period suggested that any increase in  PA  during school may highly depend on both motivation and training of general teachers . Boys may respond better to PA interventions such as the one described in this study Objectives To study correlates of change in BMI percentile and body fat among adolescent girls Design and Methods A longitudinal prospect i ve study following 265 girls from the Trial of Activity for Adolescent Girls ( TAAG ) cohort measured in 8th grade and during 10 and 11th grade or 11th and 12th grade . Twice during 2009 - 2011 girls wore an accelerometer and completed a food frequency question naire and 7-day diary documenting trips and food eaten away from home and school . Physical activity , BMI , and percent body fat were objective ly measured at each time point . Results Moderate to vigorous physical activity ( MVPA ) declined , but was not independently associated with changes in BMI percentile . Increased vigorous physical activity was associated with reductions in body fat . Diet was associated with both changes in BMI percentile and body fat . Girls who increased the percentage of caloric intake from snacks and desserts reduced their BMI percentile and body fat . Conclusions Some relationships between energy balance behaviors and BMI and body composition were counter-intuitive . While it is plausible that vigorous activity would result in reductions of body fat , until more accurate methods are devised to measure diet , the precise contribution of dietary composition to health will be difficult to assess Objective To establish in children whether inactivity is the cause of fatness or fatness the cause of inactivity . Design A non-intervention prospect i ve cohort study examining children annually from 7 to 10 years . Baseline versus change to follow-up associations were used to examine the direction of causality . Setting Plymouth , Engl and . Participants 202 children ( 53 % boys , 25 % overweight/obese ) recruited from 40 Plymouth primary schools as part of the EarlyBird study . Main outcome measures  Physical activity ( PA ) was measured using Actigraph accelerometers . The children wore the accelerometers for 7 consecutive days at each annual time point . Two components of PA were analysed : the total volume of PA and the time spent at moderate and vigorous intensities . Body fat per cent ( BF% ) was measured annually by dual energy x ray absorptiometry . Results BF% was predictive of changes in PA  over the following 3 years , but PA levels were not predictive of subsequent changes in BF% over the same follow-up period . Accordingly , a 10 % higher BF% at age 7 years predicted a relative decrease in daily moderate and vigorous intensities of 4 min from age 7 to 10 years ( r=−0.17 , p=0.02 ) , yet more PA at 7 years did not predict a relative decrease in BF% between 7 and 10 years ( r=−0.01 , p=0.8 ) . Conclusions Physical inactivity appears to be the result of fatness rather than its cause . This reverse causality may explain why attempts to tackle childhood obesity by promoting PA have been largely unsuccessful Background : Physical activity ( PA ) and sedentary time ( SED ) have both been suggested as potential risk factors for adiposity in children . However , there is paucity of data examining the temporal associations between these variables . Objective : This study aim ed to analyze the cross-sectional and prospect i ve associations between PA , SED and body composition in children . Methods : A total of 510 children ( age at baseline 10.1±0.8 , age at follow-up 11.8±0.9 ) from six Portuguese schools from the Oeiras Municipality participated in this study .  PA and SED were measured by accelerometry and trunk fat mass ( TFM ) and body fat mass ( BFM )  were measured by dual energy X-ray absorptiometry .  Fat mass index ( FMI ) was calculated as BFM divided by height squared . Several regression models adjusted for age , sex , maturity status , follow-up duration , baseline levels of the outcome variable and SED or moderate to vigorous PA ( MVPA ) were performed . Results : MVPA ( min per day ) was cross-sectionally inversely associated with adiposity indexes ( FMI , TFM and BFM ) . Adiposity indexes were inversely associated with time in MVPA . In prospect i ve analyses , MVPA was associated with a lower levels of FMI ( β=−0.37 , 95 % confidence interval ( CI ) : −0.49 to −0.26 , P<0.001 ) , TFM ( β=−0.20 , 95 % CI : −0.29 to −0.10 , P<0.001 ) and BFM ( β=−0.37 , 95 % CI : −0.49 to −0.26 , P<0.001 ) . When the model was adjusted for age , sex , maturity status and for baseline levels of the outcome variables MVPA remained a significant predictor of lower adiposity indexes ( FMI : β=−0.09 , 95 % CI : −0.16 to −0.01 , P<0.05 ; TFM : β=−0.08 , 95 % CI : −0.15 to −0.01 , P<0.05 ; BFM : β=−0.07 , 95 % CI : −0.15 to 0.00 , P<0.05 ) . Adiposity was not associated  with MVPA when modeled as the exposure in prospect i ve analyses . SED was not related with adiposity indexes , except for the relationship with FMI . Conclusions : In cross-sectional and prospect i ve analyses , MVPA is associated with lower adiposity independent of covariates and SED . Results suggest that promoting MVPA is important for preventing gain in adiposity in healthy children Objective : To determine if time spent in objective ly measured sedentary behavior is associated with a change in body mass index ( BMI ) between ages 9 and 15 years , adjusting for moderate-to-vigorous physical activity ( MVPA ) . Design : Prospect i ve observational study of children at ages 9 ( 2000 ) , 11 ( 2002 ) , 12 ( 2003 ) and 15 years ( 2006 ) .  Longitudinal quantile regression was used to model the influence of predictors on changes at the 10th , 25th , 50th , 75th and 90th BMI percentiles over time . Subjects : Participants were enrolled in the National Institute of Child Health and Human Development ( NICHD ) Study of Early Child Care and Youth Development and include both boys and girls ( n=789 ) . Measurements : Objective ly measured BMI ( kg m–2 ) was the outcome variable and objective ly measured sedentary behavior was the main predictor . Adjustment was also made for MVPA , gender , race , maternal education , hours of sleep and healthy eating index . Results : Increases in BMI were observed at all percentiles , with the greatest increase observed at the 90th BMI percentile . Spending more time in sedentary behavior  ( h per day ) was associated with additional increases in BMI at the 90th , 75th and 50th BMI percentiles , independent of MVPA and the other covariates ( 90th percentile=0.59 , 95 % confidence interval ( 95 % CI ) : 0.19–0.98 kg m–2 ; 75th percentile=0.48 , 95 % CI : 0.25–0.72 kg m–2 ; and 50th percentile=0.19 , 95 % CI : 0.05–0.33 kg m–2 ) . No associations were observed between sedentary behavior and changes at the 25th and 10th BMI percentiles . Conclusion : Sedentary behavior was associated with greater increases in BMI at the 90th , 75th and 50th BMI percentiles between ages 9 and 15 years , independent of MVPA . Preventing an increase in sedentary behavior from childhood to adolescence may contribute to reducing the number of children classified as obese PURPOSE  Physical activity ( PA  ) declines dramatically during adolescence , and activity levels are consistently lower among children living in low-income communities . Competency in a range of fundamental movement skills ( FMS ) may serve as a protective factor against the decline in PA typically observed during adolescence . The purpose of this study was to evaluate the effect of a 12-month multicomponent PA and FMS intervention on children attending primary schools in low-income communities . METHODS The Supporting Children 's Outcomes using Rewards , Exercise , and Skills intervention was evaluated using a cluster r and omized controlled trial . The sample included 25 classes from eight primary schools located in low-income communities . Participants were 460 children ( 54.1 % girls ) age 8.5 ± 0.6 yr . Primary outcomes were objective ly measured PA ( ActiGraph GT3X and GT3X+ accelerometers ) , FMS competency ( Test of Gross Motor Development 2 , six locomotor and six object control skills ) , and cardiorespiratory fitness ( 20-m multistage fitness test ) assessed at baseline , midprogram ( 6-months ) , and at posttest ( 12 months ) . Linear mixed models , adjusted for sex , age , body mass index z-score , socioeconomic status , ethnicity , and school class as a r and om factor , were used to assess the effect of the intervention . RESULTS At midprogram , there were no significant intervention effects for any of the outcomes . At posttest ( study 's primary time point ) , there were intervention effects for daily moderate-to-vigorous PA ( MVPA ) ( adjusted mean difference , 12.7 min·d of MVPA ; 95 % confidence interval ( CI ) , 5.0 - 20.5 ) , overall FMS competency ( 4.9 units ; 95 % CI , -0.04 to 9.8 ) , and cardiorespiratory fitness ( 5.4 laps ; 95 % CI , 2.3 - 8.6 ) . CONCLUSIONS A school-based multicomponent PA and FMS intervention maintained daily MVPA , improved overall FMS competency , and increased cardiorespiratory fitness among children attending primary schools in low-income communities Background Little is known about the concurrent change in  physical activity ( PA )  ,  sedentary behavior ( SB ) and  sport participation  ( SP ) during adolescence . The main purpose of this prospect i ve and partly objective study was to simultaneously investigate PA , SBs and SP changes between the 1st and 2nd grade s of high school in urban adolescents . Methods In this 1-year follow-up study , the participants were 81 secondary -school students ( 28 boys and 53 girls ) aged 15.5 years at the baseline .  PA was assessed with the SenseWear Armb and multi-sensor activity monitor , while SBs were assessed by using School Health Action , Planning and Evaluation System ( SHAPES ) PA question naire . The SHAPES question naire was supplemented with two questions inquiring about SP in organized sports in school and outside of school . Results PA decreased markedly in both genders between the 1st and 2nd grade s of high school . Total energy expenditure ( TEE ) was reduced by 13 kcal/kg/day on average in boys and by 10 kcal/kg/day in girls ( p for both < 0.001 ) , while mean daily active energy expenditure ( AEE ) decreased by 7 kcal/kg/day ( p < 0.001 ) and 3 kcal/kg/day ( p = 0.04 ) in boys and girls , respectively . Similarly , the amount of moderate PA declined by 49 min/day in boys and 21 min/day in girls ( p for both < 0.001 ) . At the same time vigorous PA was cut by 14 min/day ( p < 0.001 ) and 3 min/day ( p = 0.003 ) in boys and girls , respectively . Conversely , time spent in SBs did not show any change . Conclusion In conclusion , a decline in PA between the 1st and 2nd grade s of high school was marked but was not accompanied with an increase in SBs . Policies aim ed at increasing PA should be targeting the period of entering secondary school to offset the observed drop in PA OBJECTIVES This study aim ed to investigate cross-lagged associations of leaping skill and throwing-catching skills with objective ly measured moderate-to-vigorous physical activity ( MVPA ) and sedentary time ( ST ) during school transition from upper primary ( Grade 6 ) to lower secondary school ( Grade 7 ) . DESIGN This study is a one-year prospect i ve follow-up study within Finnish school setting s. Students '  MVPA , ST , leaping skill and throwing-catching skills were measured at Grade 6 and subsequently at Grade 7 . METHODS A sample of 336 students ( 163 girls , 173 boys ; M age=12.0 years , SD=0.4 at Grade 6 participated in the study . Students '  MVPA and ST  were measured objective ly by hip-worn accelerometers .  Leaping skill  was measured by 5-leaps test .  Throwing and catching skills were measured by throwing-catching combination test . Cross-lagged structural equation modeling was conducted to evaluate the associations between MVPA , ST , leaping skill , and throwing-catching skills at Grade 6 and Grade 7 . RESULTS Results demonstrated three significant cross-lagged associations among girls : ( 1 ) leaping skill measured at Grade 6 was negatively associated with ST at Grade 7 ; ( 2 ) objective ly measured MVPA at Grade 6 associated positively with leaping skill at Grade 7 ; and ( 3 ) throwing-catching skills measured at Grade 6 associated positively with leaping skill measured at Grade 7 . There were no statistically significant cross-lagged associations between the study variables for the sample of boys . CONCLUSIONS The results of this study indicated that supporting opportunities for girls ' engagement in both MVPA and leaping skill development activities during their primary school education is strongly recommended Background Metabolic health in people with obesity is determined by body composition . In this study , we examined the influence of a combined strength exercise and motivational programme –embedded in the school curriculum– on  adolescents body composition and daily physical activity . Methods A total of 695 adolescents ( 11 - 15y ) from nine Dutch secondary schools participated in a one year cluster r and omised controlled trial ( RCT ) . In the intervention schools , physical education teachers were instructed to spend 15–30 min of all physical education lessons ( 2 × per week ) on strength exercises . Monthly motivational lessons were given to stimulate students to be more physically active . Control schools followed their usual curriculum . The primary outcome measure was body composition assessed by the deuterium dilution technique . Daily physical activity and sedentary behaviour measured by accelerometry served as a secondary outcome . Results After 1 year , a 1.6 % fat mass difference was found in favour of the intervention group ( p = .007 ) . This reflected a 0.9 kg difference in fat free mass ( intervention > control ; p = .041 ) and 0.7 kg difference in fat mass ( intervention < control ; p = .054 ) . Daily physical activity decreased from baseline to posttest in both groups , but less so in the intervention group ( p = .049 ) . After 1 year , a difference of 0.4 % was found for moderate to vigorous physical activities in favour of the intervention group ( p = .046 ) . No differences in sedentary behaviour , or light physical activity were found between groups . Conclusion In 11–15 year olds , the combination of strength exercises plus motivational lessons contributed to an improvement in body composition and a smaller decrease in physical activity level . Trial registration ID(NTR5676 – retrospectively registered 8 February 2016 ; enrolment of first participant : 2 March 2015 ) OBJECTIVE The aims of our study were to quantify levels and investigate sex-specific changes and trajectories in VPA longitudinally from age 7 to 15 years . DESIGN Longitudinal observational study . METHODS Participants were part of the Gateshead Millennium Study . Measures were taken at age 7 ( n=507 ) , 9 ( n=510 ) , 12 ( n=425 ) and 15 years ( n=310 ) .  Vigorous physical activity was quantified objective ly using ActiGraph GT1 M accelerometers over 5 - 7days at the four time-points . Multilevel linear spline r and om-effects model and trajectory analysis to identify sub-groups were performed . RESULTS In boys , average VPA declined across childhood followed by an increase at adolescence , while in girls , average VPA declined across the 8-year study period . In boys , daily VPA decreased from 9 - 12 years ( 1.70minutes/year ) and increased from 12 - 15 years ( 1.99minutes/year ) ( all p < 0.05 ) . In girls daily VPA decreased from 7 - 9 years ( 1.70minutes/year ) ( p < 0.05 ) . Three VPA trajectories were identified which differed between the sexes . In boys , one group decreased from an initial relatively high level , one group , initially relatively low , increased , whereas the third one was stable over the 8-year period . In girls , all three groups declined from baseline . CONCLUSIONS Marked sex and age-specific trajectories in VPA change were observed . These novel findings should help sports and exercise medicine specialists , as well as policy makers , in their effort to maintain or increase VPA in childhood and adolescence IMPORTANCE The diverse developmental patterns of obesogenic behaviors during childhood and adolescence can be better understood by using new analytic approaches to assess the heterogeneity in variation during growth and development and to map the clustering of behavior patterns . OBJECTIVES To identify distinct trajectories of daily time spent in  moderate- to vigorous-intensity physical activity ( MVPA )  from ages 5 to 19 years and to examine the associations of MVPA trajectories with sports participation and television viewing trajectories . DESIGN , SETTING , AND PARTICIPANTS Cohort members in the prospect i ve population -based Iowa Bone Development Study participated in  MVPA assessment s via accelerometry from September 16 , 1998 , to December 9 , 2013 , at ages 5 , 8 , 11 , 13 , 15 , 17 , and 19 years and completed a question naire every 6 months on sports participation and daily time spent in television viewing . MAIN OUTCOMES AND MEASURES Trajectories of MVPA ( minutes per day ) , participation in organized sports ( yes or no ) , and television viewing time ( hours per day ) . RESULTS Based on the data from 537 participants ( 50.1 % females ; 94.6 % white ) , we identified 4 MVPA trajectories : consistently inactive ( 14.9 % ) , consistently active ( 18.1 % ) , decreasing moderate physical activity ( 52.9 % ) , and substantially decreasing high physical activity ( 14.1 % ) . All participants in the consistently inactive trajectory also followed a trajectory of no participation in sports . The consistently active trajectory was associated with decreasing an already low television viewing trajectory ( P < .001 ) . CONCLUSIONS AND RELEVANCE This study provided a nuanced look at the known decrease in MVPA during childhood and adolescence . Sports participation could be a critical way to avoid the consistently inactive pattern . Most important , we identified a subset of participants who maintained a seemingly healthy level of MVPA from childhood to young adulthood . The developmental pathways of physical activity and television viewing behaviors could be related . Additional studies should examine the determinants and health consequences of these specific MVPA trajectories
target: The relative decline in MVPA affects both sexes from an early age ; however , it is greater among girls .
background: Moderate-to-vigorous-intensity  physical activity ( MVPA )  is important for childhood obesity prevention and treatment , yet declines with age .
  Timing and magnitude of the decline in MVPA in children and adolescents are unclear but important for informing effective obesity intervention development .
  This systematic review aim ed to determine and compare the year-to-year changes in MVPA among children and adolescents .