Objectively measured physical activity and sedentary time: cross-sectional and prospective associations with adiposity in the Millennium Cohort Study Association between childcare educators’ practices and preschoolers’ physical activity and dietary intake: a cross-sectional analysis Adiposity and TV viewing are related to less bone accrual in young children. Cross-sectional and prospective associations between moderate to vigorous physical activity and sedentary time with adiposity in children Effects of modifying physical activity and sedentary behavior on psychosocial adjustment in overweight/obese children. Relationship between physical activity and the development of body mass index in children. Objectively measured physical activity level and sedentary behavior in Norwegian children during a week in preschool☆ Effects of Child Care Intervention on Physical Activity and Body Composition. Evaluation of policies to promote physical activity in afterschool programs: are we meeting current benchmarks? Design and baseline characteristics of the Short bouTs of Exercise for Preschoolers (STEP) study The effect of a movement-to-music video program on the objectively measured sedentary time and physical activity of preschool-aged children and their mothers: A randomized controlled trial Correlates of preschool children’s objectively measured physical activity and sedentary behavior: a cross-sectional analysis of the SPLASHY study The effect of the UP4FUN pilot intervention on objectively measured sedentary time and physical activity in 10–12 year old children in Belgium: the ENERGY-project Effects of locomotor skill program on minority preschoolers' physical activity levels. Feasibility and Effects of Short Activity Breaks for Increasing Preschool-Age Children's Physical Activity Levels. Behavioral Effects of a Locomotor-Based Physical Activity Intervention in Preschoolers. Preschool children physical activity measurement: importance of epoch length choice. Child Care Center Characteristics Associated With Preschoolers' Physical Activity. Physical activity, sedentary behavior, and adiposity in English children. Increased physical activity and reduced adiposity in overweight Hispanic adolescents. Fatness leads to inactivity, but inactivity does not lead to fatness: a longitudinal study in children (EarlyBird 45) Protocol for systematic reviews of determinants/correlates of obesity-related dietary and physical activity behaviors in young children (preschool 0 to 6 years): evidence mapping and syntheses Feasibility and Effectiveness of a Wearable Technology-Based Physical Activity Intervention in Preschoolers: A Pilot Study
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 Introduction Childcare educators may be role models for healthy eating and physical activity ( PA ) behaviours among young children . This study aim ed to identify which childcare educators ’ practice s are associated with preschoolers ’ dietary intake and PA levels . Methods This cross-sectional analysis included 723 preschoolers from 50 r and omly selected childcare centres in two Canadian provinces . All data were collected in the fall of 2013 and 2014 and analysed in the fall of 2015 .  PA was assessed using Actical accelerometers during childcare hours for 5 consecutive days .  Children ’s dietary intake  was measured at lunch on 2 consecutive days using weighed plate waste and digital photography . Childcare educators ’ nutrition practice s ( modelling , nutrition education , satiety recognition , verbal encouragement and not using food as rewards ) and PA practice s ( informal and formal PA promotion ) were assessed by direct observation over the course of 2 days , using the Nutrition and Physical Activity Self- Assessment for Child Care tool . Associations between educators ’ practice s and preschoolers ’ PA and dietary intake were examined using multilevel linear regressions . Results Overall , modelling of healthy eating was positively associated with children ’s intake of sugar ( β=0.141 , 95 % CI 0.03 to 0.27 ) , while calorie ( β=−0.456 , 95 % CI −1.46 to –0.02 ) and fibre intake ( β=−0.066 , 95 % CI −0.12 to –0.01 ) were negatively associated with providing nutrition education . Not using food as rewards was also negatively associated with fat intake ( β=−0.144 , 95 % CI −0.52 to –0.002 ) . None of the educators ’ PA practice s were associated with children ’s participation in PA  . Conclusions Modelling healthy eating , providing nutrition education and not using food as rewards are associated with children ’s dietary intake at lunch in childcare centres , highlighting the role that educators play in shaping preschoolers ’ eating behaviours . Although PA practice s were not associated with  children ’s PA levels , there is a need to reduce sedentary time in childcare centres OBJECTIVE To examine the relation between baseline fat mass and gain in bone area and bone mass in preschoolers studied prospect ively for 4 years , with a focus on the role of physical activity and TV viewing . STUDY DESIGN Children were part of a longitudinal study in which measures of fat , lean and bone mass , height , weight , activity , and diet were taken every 4 months from ages 3 to 7 years . Activity was measured by accelerometer and TV viewing by parent checklist . We included 214 children with total body dual energy x-ray absorptiometry ( Hologic 4500A ) scans at ages 3.5 and 7 years . RESULTS Higher baseline fat mass was associated with smaller increases in bone area and bone mass over the next 3.5 years ( P < .001 ) . More TV viewing was related to smaller gains in bone area and bone mass accounting for race , sex , and height . Activity by accelerometer was not associated with bone gains . CONCLUSIONS Adiposity and TV viewing are related to less bone accrual in preschoolers 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 OBJECTIVES To evaluate the relationship between changes in  physical activity ( PA ) , sedentary behavior , and physical self-perceptions and global self-worth in 30 , 8 - 12 years old , overweight/obese children ( 13 boys , 17 girls ) . METHODS Secondary analyses from a r and omized controlled trial design ed to increase PA and reduce sedentary behavior . PA was measured by accelerometers worn by participants every day for 8 weeks .  Sedentary behavior , defined as minutes per day spent in television viewing , was assessed by self-report . RESULTS Increases in PA were associated with increases in perceived physical conditioning ( r = .54 , p < .01 ) , body satisfaction ( r = .55 , p < .01 ) , and overall physical self-worth ( r = .44 , p < .05 ) independent of changes in body mass index ( BMI ) . Reductions in TV viewing were also related to increased physical and global self-worth . CONCLUSIONS Increases in PA are associated with improvements in physical self-perceptions but not global self-worth , while reductions in TV viewing are associated with increased physical and global self-worth , and these psychosocial benefits appear to be independent of changes in adiposity PURPOSE Studies estimating the contribution of physical activity ( PA ) to the development of body mass index ( BMI ) in critical periods of childhood are warranted . Therefore , we have prospect ively investigated this relationship in boys and girls of the KOALA Birth Cohort study , the Netherl and s , in the period around adiposity rebound ( i.e. , 4 - 9 yr old ) . METHODS PA was  assessed  in 470 children ( 231 boys , 239 girls ) using accelerometers at the ages of 5 and 7 yr , and height and weight were measured at 5 , 7 , and 9 yr .  BMI z-scores were calculated to st and ardize for age and sex . Leaner and heavier children were classified according to the 25th and 75th percentile of our study sample . To examine longitudinal relationships between PA and BMI z-scores , generalized estimating equation analyses were performed and stratified for sex and baseline weight status ( leaner , normal weight , and heavier children ) . RESULTS In heavier children , an increment of 6.5 min of moderate to vigorous PA ( MVPA ) was related to a subsequent decrease of 0.03 BMI z-scores both in boys ( 95 % confidence interval = -0.07 to -0.001 ) and girls ( 95 % confidence interval = -0.05 to -0.002 ) . Light PA was also associated with a decrease of BMI in heavier boys but not girls . In normal weight children , MVPA was associated with decrease of BMI in boys but not girls . CONCLUSION Increments of MVPA were associated with decreases in BMI z-score in heavier children , both boys and girls . Promoting MVPA should remain a major prevention vehicle for improving body composition in 4- to 9-yr-old children 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 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 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 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 , Regular physical activity ( PA ) and the avoidance of prolonged sitting are essential for children ’s healthy growth , and for the physical and mental wellbeing of both children and adults . In the context of exercise , music may promote behavioral change through increased exercise adherence and participation . The purpose of this study was to determine whether a movement-to-music video program could reduce sedentary behavior ( SB ) and increase PA in mother-child pairs in the home environment . A r and omized controlled trial was conducted in the Pirkanmaa region , Finl and , in 2014–2016 . The participants consisted of 228 mother-child pairs ( child age 5–7 years ) . The primary outcomes of interest were tri-axial accelerometer-derived SB and PA , which were measured in weeks one ( baseline ) , two , and eight in both the intervention and control groups . Further , the mothers and children in the intervention group used a movement-to-music video program from the beginning of week two to the end of week eight . Secondary outcomes included self-reported screen time . The statistical methods employed comprised an intention-to-treat and linear mixed effects model design . No statistically significant differences between groups were found in primary or secondary outcomes . Among the children in the control group  , light PA  decreased significantly over time and screen time increased from 89 ( st and ard deviation , SD 37 ) to 99 ( SD 41 ) min/d . Among mothers and children in the intervention group , no statistical differences were found . In supplementary analysis , the children who stayed at home instead of attending daycare/preschool had on average 25 ( 95 % confidence interval , CI 19–30 ) min/d more sedentary time and 11 ( 95 % CI 8–14 ) min/d less moderate-to-vigorous PA than those who were at daycare/preschool . The higher body mass index of mothers was related with 5 ( 95 % CI 2–7 ) min/d more sedentary time and 1 ( 95 % CI 0–2 ) min/d less moderate-to-vigorous PA . The movement-to-music video program did not change the objective ly measured SB or PA of the mother-child pairs . However , mothers and children seemed to be more sedentary at home , and therefore interventions for decreasing SB and increasing PA should be targeted in the home environment Background Identifying ways to promote physical activity and decrease sedentary time during childhood is a key public health issue . Research on the putative influences on preschool children ’s  physical activity ( PA ) and  sedentary behavior  ( SB ) is limited and has yielded inconsistent results . Our aim was to identify correlates of PA and SB in preschool children . Methods Cross-sectional data were drawn from the Swiss Preschoolers ’ Health Study ( SPLASHY ) , a Swiss population -based cohort study . Of 476 two to six year old children , 394 ( 54 % boys ) had valid PA data assessed by accelerometry .  Information on exposure data was directly measured or extracted from parental question naires . Multilevel linear regression modeling was used to separately assess associations between 35 potential correlates and  total PA ( TPA ) , moderate-to-vigorous PA ( MVPA ) and SB . Results In total , 12 correlates from different domains were identified . TPA and MVPA were greater in boys than girls , increased with age and were positively associated with gross motor skills . Children from single parent families had a higher level of TPA and spent less time sedentary than those living with two parents . Time spent outdoors was positively associated with TPA and negatively with SB . The child ’s activity temperament was related all three outcomes , whereas parental sports club membership , living area per person and neighborhood safety were associated with SB only . Fixed and r and om factors in the final models accounted for 28 % , 32 % and 22 % of the total variance in TPA , MVPA and SB , respectively . Variance decomposition revealed that age , sex and activity temperament were the most influential correlates of both , TPA and MVPA , whereas the child ’s activity temperament , time outdoors and neighborhood safety were identified as the most important correlates of SB . Conclusions A multidimensional set of correlates of young children ’s  activity behavior has been identified . Personal factors had the greatest influence on PA , whereas environmental-level factors had the greatest influence on SB . Moreover , we identified a number of previously unreported , potentially modifiable correlates of young children ’s PA and SB . These factors could serve to define target groups or become valuable targets for change in future interventions .Trial registration Current Controlled Trials IS RCT N41045021 ( date of registration : 21.03.14 ) BakckgroundThe first aim was to examine the effect of the UP4FUN pilot intervention on children ’s total sedentary time . The second aim was to investigate if the intervention had an effect on  children ’s physical activity ( PA ) level . Finally , we aim ed to investigate demographic differences ( i.e. age , gender , ethnicity , living status and having siblings ) between children in the intervention group who improved in sedentary time and PA at post-test and children in the intervention group who worsened in sedentary time and PA at post-test . Methods The six weeks UP4FUN intervention was tested in a r and omized controlled trial with pre-test post-test design with five intervention and five control schools in Belgium and included children of the 5th and 6th grade . The children wore accelerometers for seven days at pre- and post-test . Analyses included children with valid accelerometer data for at least two weekdays with minimum 10h-wearing time and one weekend day with 8h-wearing time . Result Final analyses included 372 children ( 60 % girls , mean age = 10.9 ± 0.7 years ) . There were no significant differences in the change in sedentary time or light PA between intervention and control schools for the total sample or for the subgroup analyses by gender . However , children ( specifically girls ) in the intervention group had a higher decrease in moderate-to-vigorous PA than children in the control group . In the intervention group , children who lived with both parents and children with one or more siblings were less likely to reduce sedentary time after exposure to the intervention . Older children , girls and children who lived with both parents were less likely to increase light PA after the intervention . Conclusion The UP4FUN intervention did not result in an effect on children ’s sedentary time . Based on the high amounts of accelerometer-derived sedentary time in this age group , more efforts are needed to develop strategies to reduce children ’s sedentary time This pilot study examined the effects of a teacher-taught , locomotor skill (LMS)-based physical activity ( PA ) program on the LMS and PA levels of minority preschooler-aged children . Eight low-socioeconomic status preschool classrooms were r and omized into LMS-PA ( LMS-oriented lesson plans ) or control group ( supervised free playtime ) . Interventions were delivered for 30 min/day , five days/week for six months . Changes in PA ( accelerometer ) and LMS variables were assessed with MANCOVA .  LMS-PA group exhibited a significant reduction in during-preschool ( F ( 1,16 ) = 6.34 , p = .02 , d = 0.02 ) and total daily ( F ( 1,16 ) = 9.78 , p = .01 , d = 0.30 ) percent time spent in sedentary activity .  LMS-PA  group also exhibited significant improvement in leaping skills , F ( 1 , 51 ) = 7.18 , p = .01 , d = 0.80 ) . No other , significant changes were observed . The implementation of a teacher-taught , LMS-based PA program could potentially improve LMS and reduce sedentary time of minority preschoolers 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 Poor adaptive learning behaviors ( ie , distractibility , inattention , and disruption ) are associated with behavior problems and underachievement in school , as well as indicating potential attention-deficit hyperactivity disorder . Strategies are needed to limit these behaviors . Physical activity ( PA ) has been suggested to improve behavior in school-aged children , but little is known about this relationship in preschoolers . This study examined the effects of a PA intervention on classroom behaviors in preschool-aged children . METHODS Eight preschool classrooms ( n = 71 children ; age = 3.8 ± 0.7 y ) with children from low socioeconomic environments were r and omized to a locomotor-based PA ( LB-PA ) or unstructured free playtime ( UF-PA ) group . Both interventions were implemented by classroom teachers and delivered for 30 minutes per day , 5 days per week for 6 months . Classroom behavior was measured in both groups at 3 time points ,  whereas PA  was assessed at 2 time points over a 6-month period and analyzed with hierarchical linear modeling . RESULTS Linear growth models showed significant decreases in hyperactivity ( LB-PA : -2.58 points , P = .001 ; UF-PA : 2.33 points , P = .03 ) , aggression ( LB-PA : -2.87 points , P = .01 ; UF-PA : 0.97 points , P = .38 ) and inattention ( LB-PA : 1.59 points , P < .001 ; UF-PA : 3.91 points , P < .001 ) . CONCLUSIONS This research provides promising evidence for the efficacy of LB-PA as a strategy to improve classroom behavior in preschoolers The purpose of this study was twofold : first to document the gender differences in Moderate to Vigorous Physical Activity ( MVPA ) according to two epoch systems ( 5 vs. 60 s ) in preschoolers , and , second to document the differences in physical activity ( PA ) patterns according to two different epoch choices . The sample comprised 59 preschoolers ( 31 girls ) aged 2 - 5 years old .  PA was assessed by accelerometer during school hours . The time spent in MVPA was significantly higher ( p < .001 ) when a 5-s epoch was considered compared to the 60-s epoch , regardless gender . Further , it was found a difference of ? 17 min difference between the 2 epoch systems for MVPA . Different epoch times might affect the time spent in MVPA among preschool children INTRODUCTION Despite children spending long hours in child care centers , it is unknown what center characteristics are associated with children 's  moderate to vigorous physical activity ( MVPA )  at the center and over the 24-hour day . METHODS Mixed model ANOVA evaluated associations between 23 center characteristics ( e.g. , policies , facilities , practice s , and staff training ) and  time in MVPA  , measured with accelerometers , at the child care center and over the 24-hour day among 388 preschoolers from 30 r and omly selected child care centers in Cincinnati , Ohio . Data collection occurred from November 2009 through January 2011 ; data analyses occurred in 2012 - 2014 . RESULTS Ninety percent of centers reported scheduling two or more outdoor sessions  daily , yet only 40 % of children had two or more outdoor sessions ; 32 % had no time outdoors . Eighty-three percent of centers reported scheduling ≥60 minutes outdoors  ; 28 % of children experienced this during observation . Children spent a mean ( SE ) of 2.0 ( 0.06 ) minutes/hour in MVPA . Children with ≥60 minutes outdoor time had 0.6 minutes/hour more MVPA in child care ( p=0.001 ) , and 0.5 minutes/hour over the 24-hour day ( p=0.001 ) than those who did not . Presence of an indoor play space , large outdoor playground , portable or fixed play equipment , staff PA training , weather and clothing policies , and TV/computer use were not related to children 's MVPA . CONCLUSIONS Outdoor time  occurred less frequently than scheduled . Children with ≥60 minutes of outdoor time at the center were more active than children without . Centers may increase preschoolers ' PA by adhering to the scheduled ≥60 minutes of outdoor time daily BACKGROUND The importance of variation in total volume of physical activity or moderate- to vigorous-intensity physical activity ( MVPA ) to development of body fatness in childhood is unclear , and it is unclear if physical activity has a greater influence on adiposity in boys than girls . PURPOSE To assess relationships between 2-year changes in objective ly measured physical activity , sedentary behavior , and adiposity in English children . METHODS Prospect i ve cohort study , set in Northeast Engl and , of a socioeconomically representative sample of 403 children . Measures were change in accelerometer-determined physical activity and sedentary behavior  from age 7 to 9 years ( data collected 2006/2007 and 2008/2009 ; analyzed in 2010 ) and concurrent change in adiposity ( fat mass index derived from bioelectric impedance ) and change in BMI Z-score . RESULTS Decline in MVPA was associated with a greater increase in fat mass index in boys but not girls . Declining MVPA was associated with increased BMI Z-score in boys but not girls . Increased sedentary behavior was not associated with increased BMI Z-score in either gender . CONCLUSIONS Avoiding mid-late childhood reductions in MVPA may reduce excessive fat gain , although such strategies may have greater impact on boys than girls PURPOSE The objectives of this study were to examine 1 ) whether changes in total physical activity  ( PA ; counts per minute , cpm ) and time spent in moderate to vigorous PA ( MVPA ) are associated with changes in adiposity and 2 ) whether energy intake influences the relationship between changes in PA and changes in adiposity in overweight Hispanic adolescents . METHODS Analysis included 38 overweight ( body mass index , > 85th percentile ) Hispanic adolescents with complete pretest and posttest data on relevant variables after participating in a 16-wk intervention . The intervention treatment did not influence PA , so the sample was combined and the r and omization group was adjusted for in the analysis . Body composition by dual-energy x-ray absorptiometry , 7-d PA by accelerometry , and dietary intake by 3-d diet records were assessed before and after intervention . RESULTS Within individuals , the mean increase of PA ( n = 19 ) and mean decrease of PA ( n = 19 ) was approximately 105 cpm . A 100-cpm increase in total PA was associated with a decrease of 1.3 kg of fat mass and 0.8 % body fat after adjusting for pretest adiposity , PA , age , sex , and treatment ( P < 0.05 ) . Controlling for energy intake modestly strengthened the relationships between total PA and fat mass and percent body fat . Changes in MVPA were not related to changes in adiposity after controlling for total PA ( P > 0.05 ) . CONCLUSIONS Increasing total PA  by 28 % ( 100 cpm ) was associated with a decrease of 1.4 kg of fat mass and 1 % body fat for 16 wk in overweight Hispanic adolescents independent of intervention group assignment . Increases in total PA , compared with MVPA , may be sufficient to improve body composition in overweight Hispanic adolescents 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 The aim of these review s is to inform the design and content of interventions to reduce obesity in young children . The behaviors that are associated with obesity/overweight have been studied extensively ; however , the factors associated with these behaviors in young children ( 0 to 6 years ) have not been systematic ally review ed . Over the past few years the focus of obesity prevention has shifted to preschool children because of the high prevalence of obesity at school entry and recognition that habits formed in early life could track into adulthood . In order to develop effective interventions and change behavior , it is important to underst and the factors that are associated with those behaviors . For example , we need to underst and whether it would be more important to target the family , childcare setting s or the wider environment and identify the most effective way of changing these energy balance related behaviors . Methods / Design Quantitative ( intervention and observational ) and qualitative literature on determinants/correlates of fruit and vegetable intake , sugar sweetened beverage and other unhealthy diet intake , and physical activity and sedentary behaviors in young children will be systematic ally identified , mapped and review ed . A common search strategy ( no language or period restrictions ) will be used to identify papers from eight electronic data bases and this will be supplemented by h and - search ing . Next , studies in developed countries that examine the factors associated with these behaviors in children aged 0 to 6 years ( at baseline ) will be screened and mapped descriptively followed by in-depth data extraction , quality assessment and synthesis . Data from quantitative studies will be summarized using either forest plots or harvest plots and narrative synthesis , and qualitative studies using thematic analysis . Qualitative evidence will be integrated with the quantitative evidence , using a parallel synthesis approach , to provide a deeper underst and ing of effective strategies to influence these energy balance related behaviors . Discussion In addition to updating and mapping current research , these review s will be the first to comprehensively synthesize and integrate both the quantitative and qualitative evidence pertaining to determinants/correlates/barriers/facilitators of obesity related behaviors in this young age group ( 0 to 6 years ) with the aim of informing future interventions . Systematic review registration International Prospect i ve Register for Systematic Review s ( PROSPERO ) Registration number : The purpose of this pilot study was to evaluate the feasibility and the effectiveness of an intervention that employed a technology-based physical activity ( PA ) monitoring system and teacher-regulated strategies to promote PA  in preschoolers . A total of 93 preschoolers ( 53 % girls , 4.7 years ) from 5 child care centers were recruited for a one-week intervention and r and omly assigned into control ( 2 centers , n = 45 ) or intervention ( 3 centers , n = 48 ) group . Key intervention components included : ( 1 ) wearable device-based , real-time monitoring of children ’s PA by classroom teachers and ( 2 ) teacher-regulated strategies for providing more opportunities for PA . Sedentary behavior ( SED ) and PA were measured using accelerometers . Overall , children in the intervention group showed significantly lower level of SED ( 31.6 vs. 33.6 min/h ) and higher level of total PA ( 28.4 vs. 26.4 min/h ) than children in the control group , after adjusting for age , sex , race , parent education level , parent perception of their child ’s PA , BMI , and childcare centers . Teachers in the intervention group reported that the intervention was highly feasible to be implemented in their current classroom setting s. In conclusion , we observed high acceptability and initial effectiveness of the current intervention . Subsequent research at larger-scale is warranted to fully evaluate the effectiveness of the intervention strategies tested in this study
However , total PA , sedentary behaviour , and different PA intensities were not associated with body mass index ( BMI ) or waist circumference .
Adiposity levels were lower among preschool children engaged in more ( moderate-to- ) vigorous PA compared with their peers , but no associations  between  PA and BMI or waist circumference were found
Evidence on the association between  physical activity ( PA ) and adiposity in young children is inconclusive .
A systematic review and meta-analyses were conducted to examine associations between accelerometer-derived PA and varying adiposity outcomes  in preschool children .