The relative influence of demographic, individual, social, and environmental factors on physical activity among boys and girls Development of an Accelerometer-Linked Online Intervention System to Promote Physical Activity in Adolescents Personal and social-environmental correlates of objectively measured physical activity in Norwegian pre-adolescent children. Secular and longitudinal physical activity changes in population‐based samples of children and adolescents School physical education: effect of the Child and Adolescent Trial for Cardiovascular Health. Weekend and weekday patterns of physical activity in overweight and normal-weight adolescent girls. Using Ecological Momentary Assessment to Understand Where and With Whom Adults’ Physical and Sedentary Activity Occur Out and about: association of the built environment with physical activity behaviors of adolescent females.
Background This study aim ed to evaluate the associations of selected demographic , individual , social , and environmental factors with moderate-to-vigorous physical activity ( MVPA ) in a sample of children and adolescents . Methods  MVPA  was assessed among youth ( n = 294 ) 10 - 17-years-old using the ActiGraph accelerometer . Youth completed measures of demographic and individual variables related to physical activity ( PA ) , perceived social support by parents and peers , and perceived neighborhood characteristics . Parents completed the long-form of the International Physical Activity Question naire . The Physical Activity and Media Inventory was used to measure the home environment and Geographical Information Systems software was used to measure the physical neighborhood environment . Bivariate correlations and hierarchical multiple regression were conducted stratified by gender . Results Boys participated in significantly more MVPA than girls . In hierarchical analyses , peer support , home PA equipment , and temperature were significantly associated with MVPA among boys whereas distance to the school they attended was associated with MVPA among girls . The final models accounted for 25 % and 15 % of the variance in MVPA among boys and girls , respectively . Conclusions Important differences exist among the individual , social , and environmental factors related to MVPA between boys and girls . Boys ' levels of activity appear to be influenced by factors closely linked to unstructured and social types of activities whereas girls ' activities relate to internal and external barriers as well as their proximity to their schools . The prospect i ve contribution of these important individual , social , and environmental factors to changes in MVPA among children and adolescents remains to be determined Most adolescents do not achieve the recommended levels of moderate-to-vigorous physical activity ( MVPA ) , placing them at increased risk for a diverse array of chronic diseases in adulthood . There is a great need for scalable and effective interventions that can increase MVPA in adolescents . Here we report the results of a measurement validation study and a preliminary proof-of-concept experiment testing the impact of Zamzee , an accelerometer-linked online intervention system that combines proximal performance feedback and incentive motivation features to promote MVPA . In a calibration study that parametrically varied levels of physical activity in 31 12 - 14 year-old children , the Zamzee activity meter was shown to provide a valid measure of MVPA ( sensitivity in detecting MVPA = 85.9 % , specificity = 97.5 % , and r = .94 correspondence with the benchmark RT3 accelerometer system ; all p < .0001 ) . In a subsequent r and omized controlled multi-site experiment involving 182 middle school-aged children assessed for MVPA over 6 wks , intent-to-treat analyses found that those who received access to the Zamzee intervention had average MVPA levels 54 % greater than those of a passive control group ( p < 0.0001 ) and 68 % greater than those of an active control group that received access to a commercially available active videogame ( p < .0001 ) . Zamzee ’s effects on MVPA did not diminish significantly over the course of the 6-wk study period , and were statistically significant in both females and males , and in normal- vs. high- BMI subgroups . These results provide promising initial indications that combining the Zamzee activity meter with online proximal performance feedback and incentive motivation features can positively impact MVPA levels in adolescents The aim of this study was to examine modifiable biological , psychological , behavioral and social-environmental correlates of physical activity among 1129 Norwegian 11-year-old children within a cross-sectional sample from the HEalth In Adolescents study .  Physical activity was assessed by accelerometer , and weight and height were measured objective ly . Age- and gender-specific cut-off points proposed by the International Obesity Task Force were used to define body mass index . Social-environmental variables were self-reported by question naire . Hierarchical regression ( linear mixed models ) revealed that normal weight children scored higher on percentage daily moderate-to-vigorous physical activity [ % daily moderate to vigorous physical activity ( MVPA ) ] than overweight/obese children ( P<0.001 ) . Self-efficacy ( P<0.01 ) and perceived social support from friends ( P<0.01 ) were positively associated with children 's % daily MVPA , and a negative association was found for computer/game-use on weekends ( P<0.01 ) . A moderator effect of weight category ( normal vs overweight/obese ) in the relationship between computer/game-use on weekends and % daily MVPA was detected ( P<0.05 ) , reflecting that higher computer/game-use on weekends was associated with lower % MVPA among the overweight/obese , but not among the normal weight . Modifiable correlates from multiple domains accounted for 14 % of the variance in % daily MVPA . Prospect i ve and intervention studies are needed to examine whether these factors act as mediators for physical activity change in pre-adolescent children 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 Physical inactivity is a risk behavior for cardiovascular and other diseases . Schools can promote public health objectives by increasing physical activity among youth . METHODS The Child and Adolescent Trial for Cardiovascular Health ( CATCH ) was a multicenter , r and omized trial to test the effectiveness of a cardiovascular health promotion program in 96 public schools in four states . A major component of CATCH was an innovative , health-related physical education ( P+ ) program . For 2.5 years , r and omly assigned schools received a st and ardized PE intervention , including curriculum , staff development , and follow-up . RESULTS Systematic analysis of 2,096 PE lessons indicated students engaged in more moderate-to-vigorous physical activity ( MVPA ) in intervention than in control schools ( P = 0.002 ) . MVPA during lessons in intervention schools increased from 37.4 % at baseline to 51.9 % , thereby meeting the established Year 2000 objective of 50 % . Intervention children reported 12 more min of daily vigorous physical activity ( P = 0.003 ) and ran 18.6 yards more than control children on a 9-min run test of fitness ( P = 0.21 ) . CONCLUSIONS The implementation of a st and ardized curriculum and staff development program increased children 's  MVPA in existing school PE classes in four geographic and ethnically diverse communities . CATCH PE provides a tested model for improving physical education in American schools OBJECTIVE To describe the patterns ( specifically comparing weekdays and weekends classified by intensities ) of  physical activity ( PA ) measured by accelerometry in adolescent girls . RESEARCH METHODS AND PROCEDURES Healthy sixth grade girls ( n=1603 ) , 11 to 12 years old , were r and omly recruited from 36 schools participating in the Trial of Activity in Adolescent Girls . Age , ethnicity , socioeconomic status , weight , and height were taken .  PA patterns were measured for 6 days using accelerometry . RESULTS Adolescent girls spend most of their time in  sedentary  ( 52 % to 57 % of the day ) and  light activity ( 40 % to 45 % of the day ) on weekdays and weekends . In all girls , total PA  comprised 44.5 % of the day ( 41.7 % light , 2.2 % moderate , and 0.7 % vigorous ) with sedentary activity comprising 55.4 % .  Moderate-to-vigorous PA ( MVPA )  was higher ( p<0.001 ) on weekdays than weekends in all girls , but  MVPA  was lower in at-risk of overweight+overweight girls ( p<0.001 ) on both weekdays and weekends compared with normal-weight girls . DISCUSSION Adolescent girls are more active at moderate and vigorous intensities on weekdays than on weekends , and at-risk of overweight and those overweight spend less time engaging in  MVPA  than normal-weight girls Purpose This study used Ecological Momentary Assessment ( EMA ) , a real-time self-report strategy , to describe the physical and social context s of adults ’ physical activity and sedentary activity during their everyday lives and to determine whether these patterns and relationships differ for men and women . Methods Data from 114 adults were collected through mobile phones across 4 days . Eight electronic EMA surveys were r and omly prompted each day asking about current activities ( e.g. , physical or sedentary activity ) , physical and social context s , and perceived outdoor environmental features ( e.g. , greenness/vegetation , safety , and traffic ) . All participants also wore accelerometers during this period to objective ly measure moderate-to-vigorous physical activity ( MVPA ) and sedentary activity . Results Home was the most common physical context for EMA-reported physical and sedentary activity . Most of these activities occurred when participants were alone . When alone , the most commonly EMA-reported physical activity and sedentary activity was walking and reading/using computer , respectively . When in outdoor home locations ( e.g. , yard and driveway ) women demonstrated higher levels of MVPA , whereas men demonstrated higher levels of MVPA when in outdoor park setting s ( ps < .05 ) . Men but not women demonstrated higher levels of MVPA in setting s with a greater degree of perceived greenness and vegetation ( p < .05 ) . Conclusions The current study shows how EMA via mobile phones and accelerometers can be combined to offer an innovative approach to assess the context s of adults ’ daily physical and sedentary activity . Future studies could consider utilizing this method in more representative sample s to gather context -specific information to inform the development of physical activity interventions Locational data , logged on portable GPS units and matched with accelerometer data , was used to examine associations of the built environment with physical activity and  sedentary behaviors of adolescent females . In a sample of 293 adolescent females aged 15 to 18 years old in Minneapolis and San Diego , the built environment around each GPS point and its corresponding sedentary , light , and moderate-to-vigorous intensity physical activity was examined using r and om intercept multinomial logistic regression models . The odds of higher physical activity intensity ( 3-level outcome : sedentary , light , MVPA ) were higher in places with parks , schools , and high population density , during weekdays , and lower in places with more roads and food outlets . Underst and ing the places where physical activity and sedentary behaviors occur appears to be a promising strategy to clarify relationships and inform policy aim ed at increasing physical activity and reducing sedentary behaviors
MVPA in children/adolescents with chronic disease appear to be well below guideline recommendations , although comparable with activity levels of their healthy peers except for children with malignancies .
CONTEXT Moderate-to-vigorous physical activity ( MVPA ) and sedentary time ( ST )  are important for child and adolescent health .
OBJECTIVE To examine habitual levels of accelerometer measured MVPA and ST  in children and adolescents with chronic disease , and how these levels compare with healthy peers .