A Novel Approach to Characterize Physical Activity Patterns in Preschool-Aged Children Feasibility trial evaluation of a physical activity and screen-viewing course for parents of 6 to 8 year-old children: Teamplay Assessment of a two-year school-based physical activity intervention among 7-9-year-old children Objectively measured physical activity level and sedentary behavior in Norwegian children during a week in preschool☆ Evaluation of policies to promote physical activity in afterschool programs: are we meeting current benchmarks? Secular and longitudinal physical activity changes in population‐based samples of children and adolescents A comprehensive physical activity promotion programme at elementary school: the effects on physical activity, physical fitness and psychosocial correlates of physical activity. Objectively measured physical activity in four-year-old British children: a cross-sectional analysis of activity patterns segmented across the day Feasibility and Effects of Short Activity Breaks for Increasing Preschool-Age Children's Physical Activity Levels. Can we skill and activate children through primary school physical education lessons? "Move it Groove it"--a collaborative health promotion intervention. Greater Adherence to Recommended Morning Physical Activity is Associated With Greater Total Intervention-Related Physical Activity Changes in Bariatric Surgery Patients. Objectively measured physical activity and sedentary time: cross-sectional and prospective associations with adiposity in the Millennium Cohort Study Physical activity, diet and BMI in children aged 6–8 years: a cross-sectional analysis Effects of Child Care Intervention on Physical Activity and Body Composition. Design and baseline characteristics of the Short bouTs of Exercise for Preschoolers (STEP) study How active are our children? Findings from the Millennium Cohort Study The Physical Activity 4 Everyone Cluster Randomized Trial: 2-Year Outcomes of a School Physical Activity Intervention Among Adolescents.
Objective Routine moderate-to-vigorous physical activity ( MVPA ) is associated with better health outcomes ; the purpose of this work was to evaluate healthy preschooler physical activity patterns with objective measurement . Methods and Procedures An objective prospect i ve study of fifty normally-developing children 3–5 years old who were ≥50th and < 95th BMI percentile and enrolled in a family-based healthy lifestyle study in 2011–2012 . Participants wore a tri-axial accelerometer for 7 continuous days . Outcome measures consisted of wear time examining four common MVPA patterns : isolated spurt ( IS ) , isolated sustained activity ( ISA ) , clustered spurt ( CS ) , and clustered sustained activity ( CSA ) . Results Participants were 4.3 years , 56 % female , 52 % African-American , and 26 % overweight . Forty-five children met wear time criteria . On average , children spent 14.5 % of wake-wear time in MVPA , requiring 11.3 hours to complete 90 % of their daily MVPA . Children spent the majority of MVPA in CS ( 62.1 % , followed by CSA ( 20.1 % ) . Remaining MVPA was spent in IS ( 15.5 % ) and ISA ( 2.3 % ) . Conclusion It takes most of the waking day for preschoolers to attain their PA . They engage in short spurts of small duration , in four common MVPA patterns . Utilizing this method could better characterize preschooler physical activity needs in practice and policy guidelines Background Many children spend too much time screen-viewing ( watching TV , surfing the internet and playing video games ) and do not meet physical activity ( PA ) guidelines . Parents are important influences on children ’s PA and screen-viewing ( SV ) . There is a shortage of parent-focused interventions to change children ’s PA and SV . Methods Teamplay was a two arm individualized r and omized controlled feasibility trial . Participants were parents of 6–8 year old children . Intervention participants were invited to attend an eight week parenting program with each session lasting 2 hours . Children and parents wore an accelerometer for seven days and minutes of moderate-to-vigorous intensity PA ( MVPA )  were derived . Parents were also asked to report the average number of hours per day that both they and the target child spent watching TV . Measures were assessed at baseline ( time 0 ) at the end of the intervention ( week 8) and 2 months after the intervention had ended ( week 16 ) . Results There were 75 participants who provided consent and were r and omized but 27 participants withdrew post-r and omization . Children in the intervention group engaged in 2.6 fewer minutes of weekday MVPA  at Time 1 but engaged in 11 more minutes of weekend MVPA . At Time 1 the intervention parents engaged in 9 more minutes of  weekday MVPA  and 13 more minutes of weekend MVPA  . The proportion of children in the intervention group watching ≥ 2 hours per day of TV on weekend days decreased after the intervention ( time 0 = 76 % , time 1 = 39 % , time 2 = 50 % ) , while the control group proportion increased slightly ( 79 % , 86 % and 87 % ) . Parental weekday TV watching decreased in both groups . In post- study interviews many mothers reported problems associated with wearing the accelerometers . In terms of a future full-scale trial , a sample of between 80 and 340 families would be needed to detect a mean difference of 10-minutes of weekend MVPA . Conclusions Teamplay is a promising parenting program in an under- research ed area . The intervention was acceptable to parents , and all elements of the study protocol were successfully completed . Simple changes to the trial protocol could result in more complete data collection and study engagement 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 Although many studies have reported on  physical activity ( PA ) levels using accelerometers , a thorough description of the PA pattern in preschool children during their stay in the preschool , is lacking in the current literature . Furthermore , there remains a lack of underst and ing of the PA level and pattern in children in the lower end of the PA continuum . The first aim of this study was therefore to describe the PA pattern during a week-long stay in a preschool in all children born in 2011 ( either three or four-year-olds ) attending public preschools in a municipality in Norway . The second aim was to describe the PA level and pattern of the children who are the least physically active . This cross-sectional study included baseline data from 95 % of children ( N = 111 ) participating in a r and omized controlled physical activity intervention ( Active Kindergarten – Active Children study ) . The participants wore an Actigraph accelerometer , in week 39 in 2015 , from when they arrived at the preschool on Monday morning and throughout their stay of five consecutive days . The amount of moderate- to vigorous-intensity PA ( MVPA ) per day ranged from 16 min to 116 min , and sedentary time ranged from 2.7 h to 6.5 h per day in the least and most sedentary child , respectively . The least physically active 25 % of children were less active throughout the entire day , and only a few of them managed to achieve the recommended level of MVPA on any weekday . The physical activity levels and patterns among the least active children described in this study may help to inform interventions targeting this group BACKGROUND Policies now recommend afterschool programs ( ASP , 3 - 6 pm ) provide children a minimum amount of physical activity daily . We examined the extent to which children attending ASPs meet existing national and state-level policies that specify expected levels of physical activity ( PA ) . METHODS Accelerometer-derived physical activity ( light and moderate-to-vigorous , MVPA ) of 253 children ( 5 - 13 years ) was compared to policies that recommend varying amounts of PA children should achieve during an ASP . RESULTS The proportion of children achieving a policy ranged from 0.0 % ( California 60 min MVPA and North Carolina 20 % of daily program time devoted to MVPA ) , 1.2 % ( California 30 min MVPA ) , to 48.2 % ( National Afterschool Association 30 min light plus MVPA ) . R and om effects logistic models indicated boys ( odds ratio [ OR ] range 2.0 to 6.27 ) and children from a minority background ( Black/Hispanic , OR range 1.87 to 3.98 ) were more likely to achieve a recommended level of physical activity , in comparison to girls and White children . Neither age nor BMI were related to achieving a policy . CONCLUSIONS The PA of children attending ASP falls below policy recommended levels ; however , these policies were developed in absence of data on expected PA levels during ASPs . Thus , concerted effort towards building a stronger ASP evidence -base for policy refinement is required 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 OBJECTIVE To evaluate the effects of a comprehensive physical activity ( PA ) promotion programme in elementary schools on children 's total PA levels , leisure-time PA , physical fitness and psychosocial correlates of PA . DESIGN A pre-test-post-test design over two school years . SETTING AND SUBJECTS Sixteen elementary schools ( 764 children , mean age : 11.2 + /- 0.7 years ) were r and omly assigned to the intervention condition ( n = 8) and the control condition ( n = 8) . The intervention included a health-related physical education programme , an extracurricular PA promotion programme and classroom-based PA education lessons . In the total sample , leisure-time PA , psychosocial correlates of PA and physical fitness were measured using a PA question naire and the Eurofit test battery . In a sub- sample , total PA levels were measured using an accelerometer . RESULTS According to accelerometer data , children 's moderate PA and moderate-to-vigorous PA ( MVPA ) levels decreased less in the intervention schools than in the control schools ( P < 0.01 ) . The average time spent on MVPA decreased by 9 min per day in the intervention schools compared with 33 min per day in the control schools . Children in the intervention schools reported significantly more moderate PA in leisure time than the controls ( P < 0.05 ) . No overall improvement of physical fitness and no effects on the psychosocial correlates of PA were found . CONCLUSIONS The comprehensive PA promotion programme was successful in preventing a decline in children 's  total activity levels . Furthermore , the intervention increased children 's PA engagement in leisure time . Therefore , implementation needs to be encouraged Background Little is known about preschool-aged children ’s levels of  physical activity ( PA ) over the course of the day . Using time-stamped data , we describe the levels and patterns of PA in a population -based sample of four-year-old British children . Methods Within the Southampton Women ’s Survey the PA levels of 593 4-year-old children ( 51 % female ) were measured using ( Actiheart ) accelerometry for up to 7 days . Three outcome measures : minutes spent sedentary ( < 20 cpm ) ; in light ( LPA : ≥20 – 399 cpm ) and in moderate-to-vigorous activity ( MVPA : ≥400 cpm ) were derived . Average daily activity levels were calculated and then segmented across the day ( morning , afternoon and evening ) . MVPA was log-transformed . Two-level r and om intercept models were used to analyse associations between activity level and temporal and demographic factors . Results Children were active for 67 % ( mean 568.5 SD 79.5 minutes ) of their daily registered time on average , with 88 % of active time spent in LPA . All children met current UK guidelines of 180 minutes of daily activity . There were no differences in children ’s average daily levels of sedentary activity and LPA by temporal and demographic factors : differences did emerge when activity was segmented across the day . Sex differences were largest in the morning , with girls being more sedentary , spending fewer minutes in LPA and 18 % less time in MVPA than boys . Children were more sedentary and less active ( LPA and MVPA ) in the morning if they attended childcare full-time compared to part-time , and on weekend mornings compared to weekdays . The reverse was true for weekend afternoons and evenings . Children with more educated mothers were less active in the evenings . Children were less sedentary and did more MVPA on summer evenings compared to winter evenings . Conclusions Preschool-aged children meet current physical activity guidelines , but with the majority of their active time spent in LPA , investigation of the importance of activity intensity in younger children is needed . Activity levels over the day differed by demographic and temporal factors , highlighting the need to consider temporality in future interventions . Increasing girls ’ morning activity and providing opportunities for daytime activity in winter months may be worthwhile BACKGROUND We examined the effects of short bouts of structured physical activity ( SBS-PA ) implemented within the classroom setting as part of design ated gross-motor playtime on preschoolers PA . METHODS Preschools were r and omized to SBS-PA ( centers , N = 5 ; participants , N = 141 ) or unstructured free playtime ( UPA ) ( centers , N = 5 ; participants , N = 150 ) .  SBS-PA consisted of structured PA implemented in the classroom during the first 10 minutes of gross-motor playtime followed by 20 minutes of free playtime . UPA consisted of 30 minutes of unstructured free playtime . Teachers implemented both conditions for 5 days/week for 6 months . PA was assessed with accelerometers ( preschool-day ) and direct observation ( 30-minute sessions ) . Generalized linear mixed models were used to examine the impact of the intervention . RESULTS Regarding the 30-minute sessions , significant group main effects were observed for intervals spent at light ( p < .001 ) and moderate-to-vigorous PA ( MVPA , p < .001 ) . Regarding the preschool-day PA , significant group by visit interaction was observed for percent time spent in total preschool-day MVPA ( F ( 2 , 254 ) = 3.54 , p = .03 ) . Percent of time spent in MVPA significantly decreased in both groups at 3 months and at 6 months . CONCLUSION SBS-PA can be implemented in classroom setting s ; however , further research is needed to examine its impact on preschoolers PA levels BACKGROUND Physical education ( PE ) lessons are an ideal setting to improve child fundamental movement skills ( FMSs ) and increase physical activity ( PA ) for optimal health . Despite this , few studies have assessed the potential to do both simultaneously . The " Move It Groove It " primary school intervention in New South Wales , Australia , had this opportunity . METHODS A whole school approach to implementation included establishment of school project teams , a teacher " buddy " system , project Web site , teacher training workshops , and small grants for equipment . The quasi-experimental evaluation involved 1,045 year 3 and 4 children ( aged 7 to 10 years ) in nine intervention and nine control rural primary schools ( 53 % boys/47 % girls ) . It utilised pre- and postobservational surveys of ( 1 ) mastery or near mastery levels for each of eight FMSs , ( 2 ) proportion of PE lesson time spent in moderate to vigorous PA ( MVPA ) and vigorous PA ( VPA ) , and ( 3 ) teacher- and lesson-related context ual covariates . Data were analysed by hierarchical logistic multiple regression . RESULTS For FMSs , overall mastery or near mastery level at baseline was 47 % ranging from 22.7 % for the overarm throw among girls to 75.4 % for the static balance among boys . The intervention delivered substantial improvements in every FMS for both genders ranging from 7.2 % to 25.7 % ( 13 of 16 comparisons were significant ) . For PA level , mean MVPA at baseline was 34.7 % . Baseline MVPA for boys was 38.7 % and for girls was 33.2 % . The intervention was associated with a nonsignificant 4.5 % increase in MVPA and a significant 3.0 % increase in VPA . This translates to a gain of < 1 minute of MVPA per average 21-minute lesson . CONCLUSIONS This is the first study to show that by modifying existing PE lessons , significant improvements in FMS mastery can be gained without adversely affecting children 's MVPA and VPA . To increase PA levels , we recommend increasing the number of PE lessons per week BACKGROUND This study examines whether performance of bout-related physical activity ( PA ) during morning hours is related to greater overall bout-related PA increases within a preoperative PA intervention for bariatric surgery ( BS ) patients . METHODS Participants with severe obesity ( n = 33 ; mean age = 45.6 ± 9.6 years ; BMI = 45.7 ± 7.0 kg/m2 ) seeking BS were r and omized to and completed 6 weeks of preoperative PA counseling ( retention = 82.5 % ) . Participants were encouraged to walk daily at a moderate intensity in bouts ≥ 10 minutes during morning hours to overcome time-related obstacles and establish a PA habit . Timing and amount of bout-related moderate-to-vigorous PA ( MVPA )  was assessed via objective monitor at pre- and postintervention . RESULTS Greater proportion of bout-related MVPA performed during morning hours ( 4:00 AM-12:00 PM ) at postintervention was associated with larger total increases in bout-related MVPA minutes/day ( β = .40 , P = .03 ) . At postintervention , a greater proportion of participants whose longest MVPA bouts occurred during morning hours ( n = 11 ) achieved the public health guideline ( ie , ≥150 bout-related MVPA minutes/week ) versus those whose longest MVPA bouts occurred during nonmorning hours ( n = 19 ; 63.6 % vs. 26.3 % , P = .04 ) . CONCLUSIONS Intervention-related increases in PA  tended to be greatest when PA was performed in the morning . Morning exercise may be a viable strategy for promoting habitual PA in inactive BS patients 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 Objective To assess relationships between current physical activity ( PA ) , dietary intake and body mass index (  BMI ) in English children . Design and setting Longitudinal birth cohort study in northeast Engl and , cross-sectional analysis . Participants 425 children ( 41 % of the original cohort ) aged 6–8 years ( 49 % boys ) . Main outcome measures  PA  over 7 days was measured objective ly by an accelerometer ; three categories of PA were created : ‘ active ’ ≥60 min/day moderate-to-vigorous-intensity PA ( MVPA ) ; ‘ moderately active ’ 30–59 min/day MVPA ; ‘ inactive ’ < 30 min/day MVPA . Dietary intake  over 4 days was measured using a prospect i ve dietary assessment tool which incorporated elements of the food diary and food frequency methods . Three diet categories were created : ‘ healthy ’ , ‘ unhealthy ’ and ‘ mixed ’ , according to the number of portions of different foods consumed . Adherence to the ‘ 5-a-day ’ recommendations for portions of fruit and vegetables was also assessed . Children were classified as ‘ healthy weight ’ or ‘ overweight or obese ’ ( OW/OB ) according to International Obesity Taskforce cutpoints for BMI . Associations between weight status and PA/diet categories were analysed using logistic regression . Results Few children met the UK-recommended guidelines for either MVPA or fruit and vegetable intake , with just 7 % meeting the recommended amount of MVPA of 60 min/day , and 3 % meeting the 5-a-day fruit and vegetable recommendation .  Higher PA  was associated with a lower OR for OW/OB in boys only ( 0.20 , 95 % CI 0.04 to 0.88 ) . There was no association detected between dietary intake and OW/OB in either sex . Conclusions Increasing MVPA may help to reduce OW/OB in boys ; however , more research is required to examine this relationship in girls . Children are not meeting the UK guidelines for diet and PA , and more needs to be done to improve this situation INTRODUCTION This study evaluated whether intervening with child care providers would increase physical activity ( PA )  and reduce adiposity in preschoolers . METHODS This was a two-arm , parallel group , cluster RCT whereby six child care centers were r and omly assigned in equal numbers to intervention ( n=40 children ) or control ( n=43 children ) . Participants were aged 3 - 5 years and attended licensed child care centers . Child care providers received two 3-hour train-the-trainer workshops and a training manual at program initiation aim ed at increasing structured and unstructured PA through active play . Control child care centers implemented their st and ard curriculum .  PA and sedentary behavior were measured by accelerometry , and body composition was measured using bioelectrical impedance at baseline and 6 months . Data were collected in 2011 - 2012 and analyzed in April 2015 . RESULTS Linear mixed-effects modeling showed that at 6 months , children in the intervention group demonstrated greater increases in minutes per preschool day spent in overall PA ( 22.5 minutes , 95 % CI=8.9 , 36.1 , p=0.002 ) , and light-intensity PA ( 16.1 minutes , 95 % CI=5.2 , 26.7 , p=0.004 ) , but changes between groups in moderate to vigorous PA did not differ . The intervention group showed greater reductions in body fat percentage ( -1.9 % , 95 % CI=-3.5 , -0.3 , p=0.023 ) and fat mass ( -0.3 kg , 95 % CI=-0.7 , -0.1 , p=0.018 ) , but groups did not differ on fat-free mass , BMI , or z- BMI . CONCLUSIONS Provider-led intervention in child care centers increased preschoolers '  PA and reduced adiposity , therefore may represent a viable approach to promoting PA and related health benefits in preschool-aged children . TRIAL REGISTRATION This study is registered at www . clinical trials.gov NCT02293278 Background Most preschool centers provide two 30-min sessions of gross-motor/outdoor playtime per preschool day . Within this time frame , children accumulate most of their activity within the first 10 min . This paper describes the design and baseline participant characteristics of the Short bouTs of Exercise for Preschoolers ( STEP ) study . The STEP study is a cluster r and omized controlled study design ed to examine the effects of short bouts of structured physical activity ( SBS-PA ) implemented within the classroom setting as part of design ated gross-motor playtime on during-school physical activity ( PA ) in preschoolers . Methods / Design Ten preschool centers serving low-income families were r and omized into  SBS-PA versus unstructured PA ( UPA ) . SBS-PA schools were asked to implement age-appropriate 10 min structured PA routines within the classroom setting , twice daily , followed by 20 min of usual unstructured playtime . UPA intervention consisted of 30 min of supervised unstructured free playtime twice daily . Interventions were implemented during the morning and afternoon design ated gross-motor playtime for 30 min/session , five days/week for six months . Outcome measures were between group difference in during-preschool PA ( accelerometers and direct observation ) over six-months . Ten preschool centers , representing 34 classrooms and 315 children , enrolled in the study . The average age and BMI percentile for the participants was 4.1 ± 0.8 years and 69th percentile , respectively . Participants spent 74 % and 6 % of their preschool day engaged in sedentary and MVPA , respectively . Discussion Results from the STEP intervention could provide evidence that a PA policy that exposes preschoolers to shorter bouts of structured PA throughout the preschool day could potentially increase preschoolers ’ PA levels . Trial registration Clinical trials.gov , Objective To describe levels of physical activity , sedentary time and adherence to Chief Medical Officers ( CMO ) physical activity guidelines among primary school-aged children across the UK using objective accelerometer-based measurements . Design Nationally representative prospect i ve cohort study . Setting Children born across the UK , between 2000 and 2002 . Participants 6497 7-year-old to 8-year-old singleton children for whom reliable accelerometer data were available for at least 10 h a day for at least 2 days . Main outcome measures Physical activity in counts per minute ( cpm ) ; time spent in sedentary and moderate-to-vigorous intensity physical activity ( MVPA ) ; proportion of children meeting CMO guidelines ( ≥60 min/day MVPA ) ; average daily steps . Explanatory measures Gender , ethnicity , maternal current/most recent occupation , lone parenthood status , number of children in the household and country/region of residence . Results The median daily physical activity level was 595 cpm ( IQR 507 , 697 ) . Children spent a median of 60 min ( IQR 47–76 ) in MVPA/day and were sedentary for a median of 6.4 h/day ( IQR 6–7 ) . Only 51 % met CMO guidelines , with girls ( 38 % ) less active than boys ( 63 % ) . Children took an average of 10 229 ( 95 % CI ( 8777 to 11 775 ) ) steps each day . Children of Indian ethnicity were significantly less active overall than all other ethnic groups . Children of Bangladeshi origin and those living in Northern Irel and were least likely to meet CMO guidelines . Conclusions Only half of 7-year-old children in the UK achieve recommended levels of physical activity , with significant gender , ethnic and geographic variations . Longitudinal studies are needed to better underst and the relevance of these (in)activity patterns for long-term health and well-being . In the meantime population -wide efforts to boost physical activity among young people are needed which are likely to require a broad range of policy interventions 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
METHODS The results of recent systematic review s are discussed and supplemented with relevant literature not included in these review s. PubMed was search ed for the years 2006 - 2011 for additional topics not sufficiently covered by the review s. RESULTS PA was associated with lower blood pressure and a healthier lipid blood profile in children .
The association was stronger when a composite risk factor score was analysed , and the associations between physical fitness and cardiovascular disease ( CVD ) risk factors were even stronger .
Muscle strength and endurance exercise each had an effect on blood lipids and insulin sensitivity even if the effect was smaller for muscle strength than for aerobic exercise .
New evidence suggests possible effects of PA  on C-reactive protein .
CONCLUSION There is accumulating evidence that PA can have beneficial effects on the risk factors of CVD in children .
BACKGROUND A number of recent systematic review s have result ed in changes in international recommendations for children 's participation in physical activity ( PA ) for health .
The World Health Authority ( WHO ) has recently released new recommendations .
The WHO still recommends 60 min of moderate to vigorous physical activity ( MVPA ) , but also emphasises that these minutes should be on top of everyday physical activities .
Everyday physical activities total around 30 min of MVPA in the quintile of the least active children , which means that the new recommendations constitute more activity in total compared with earlier recommendations .
OBJECTIVE To summarise evidence justifying new PA recommendation for cardiovascular health in children .