title: Breaking prolonged sitting reduces postprandial glycemia in healthy, normal-weight adults: a randomized crossover trial. Criterion and Concurrent Validity of the activPAL™ Professional Physical Activity Monitor in Adolescent Females Breaking Up Prolonged Sitting Reduces Postprandial Glucose and Insulin Responses Predictive Validity and Classification Accuracy of ActiGraph Energy Expenditure Equations and Cut-Points in Young Children MVPA Is Associated with Lower Weight Gain in 8–10 Year Old Children: A Prospective Study with 1 Year Follow-Up A cluster-randomized controlled trial to reduce sedentary behavior and promote physical activity and health of 8-9 year olds: The Transform-Us! Study Objectively Measured Sedentary Time May Predict Insulin Resistance Independent of Moderate- and Vigorous-Intensity Physical Activity Physical activity, sedentary behavior, and adiposity in English children. Cross-sectional and prospective associations between moderate to vigorous physical activity and sedentary time with adiposity in children Relationship between the intensity of physical activity, inactivity, cardiorespiratory fitness and body composition in 7–10-year-old Dublin children A longitudinal study of sedentary behavior and overweight in adolescent girls. The prevalence of sedentary behavior and physical activity in leisure time: A study of Scottish adolescents using ecological momentary assessment. Time spent in sedentary behavior and changes in childhood BMI: a longitudinal study from ages 9 to 15 years Comparison of accelerometer cut points for predicting activity intensity in youth. The impact of stand-biased desks in classrooms on calorie expenditure in children.
abstract: BACKGROUND Sedentary behavior is a risk factor for cardiometabolic disease . Regularly interrupting sedentary behavior with activity breaks may lower this risk . OBJECTIVE We compared the effects of prolonged sitting , continuous physical activity combined with prolonged sitting , and regular activity breaks on  postpr and ial metabolism . DESIGN Seventy adults participated in a r and omized crossover study . The prolonged sitting intervention involved sitting for 9 h , the physical activity intervention involved walking for 30 min and then sitting , and the regular-activity-break intervention involved walking for 1 min 40 s every 30 min . Participants consumed a meal-replacement beverage at 60 , 240 , and 420 min . RESULTS The plasma incremental area under the curve ( iAUC ) for insulin differed between interventions ( overall P < 0.001 ) . Regular activity breaks lowered values by 866.7 IU · L(-1 ) · 9 h(-1 ) ( 95 % CI : 506.0 , 1227.5 IU · L(-1 ) · 9 h(-1 ) ; P < 0.001 ) when compared with prolonged sitting and by 542.0 IU · L(-1 ) · 9 h(-1 ) ( 95 % CI : 179.9 , 904.2 IU · L(-1 ) · 9 h(-1 ) ; P = 0.003 ) when compared with physical activity . Plasma glucose iAUC also differed between interventions ( overall P < 0.001 ) . Regular activity breaks  lowered values by 18.9 mmol · L(-1 ) · 9 h(-1 ) ( 95 % CI : 10.0 , 28.0 mmol · L(-1 ) · 9 h(-1 ) ; P < 0.001 ) when compared with prolonged sitting and by 17.4 mmol · L(-1 ) · 9 h(-1 ) ( 95 % CI : 8.4 , 26.3 mmol · L(-1 ) · 9 h(-1 ) ; P < 0.001 ) when compared with physical activity . Plasma triglyceride iAUC differed between interventions ( overall P = 0.023 ) . Physical activity  lowered values by 6.3 mmol · L(-1 ) · 9 h(-1 ) ( 95 % CI : 1.8 , 10.7 mmol · L(-1 ) · 9 h(-1 ) ; P = 0.006 ) when compared with regular activity breaks . CONCLUSION Regular activity breaks were more effective than continuous physical activity at decreasing postpr and ial glycemia and insulinemia in healthy , normal-weight adults . This trial was registered with the Australian New Zeal and Clinical Trials registry as ACTRN12610000953033 Background The activPAL has been identified as an accurate and reliable measure of sedentary behaviour . However , only limited information is available on the accuracy of the activPAL activity count function as a measure of physical activity , while no unit calibration of the activPAL has been completed to date . This study aim ed to investigate the criterion validity of the activPAL , examine the concurrent validity of the activPAL , and perform and vali date a value calibration of the activPAL in an adolescent female population . The performance of the activPAL in estimating posture was also compared with sedentary thresholds used with the ActiGraph accelerometer . Method ologies Thirty adolescent females ( 15 developmental ; 15 cross-validation ) aged 15–18 years performed 5 activities while wearing the activPAL , ActiGraph GT3X , and the Cosmed K4B2 . A r and om coefficient statistics model examined the relationship between metabolic equivalent ( MET ) values and activPAL counts . Receiver operating characteristic analysis was used to determine activity thresholds and for cross-validation . The r and om coefficient statistics model showed a concordance correlation coefficient of 0.93 ( st and ard error of the estimate = 1.13 ) . An optimal moderate threshold of 2997 was determined using mixed regression , while an optimal vigorous threshold of 8229 was determined using receiver operating statistics . The activPAL count function demonstrated very high concurrent validity ( r = 0.96 , p<0.01 ) with the ActiGraph count function . Levels of agreement for sitting , st and ing , and stepping between direct observation and the activPAL and ActiGraph were 100 % , 98.1 % , 99.2 % and 100 % , 0 % , 100 % , respectively . Conclusions These findings suggest that the activPAL is a valid , objective measurement tool that can be used for both the measurement of physical activity and sedentary behaviours in an adolescent female population OBJECTIVE Observational studies show breaking up prolonged sitting has beneficial associations with cardiometabolic risk markers , but intervention studies are required to investigate causality . We examined the acute effects on postpr and ial glucose and insulin levels of uninterrupted sitting compared with sitting interrupted by brief bouts of light- or moderate-intensity walking . RESEARCH DESIGN AND METHODS Overweight/obese adults ( n = 19 ) , aged 45–65 years , were recruited for a r and omized three-period , three-treatment acute crossover trial : 1 ) uninterrupted sitting ; 2 ) seated with 2-min bouts of light-intensity walking every 20 min ; and 3 ) seated with 2-min bouts of moderate-intensity walking every 20 min . A st and ardized test drink was provided after an initial 2-h period of uninterrupted sitting . The positive incremental area under curves ( iAUC ) for glucose and insulin ( mean [ 95 % CI ] ) for the 5 h after the test drink ( 75 g glucose , 50 g fat ) were calculated for the respective treatments . RESULTS The glucose iAUC ( mmol/L ) ⋅ h after both activity-break conditions was reduced ( light : 5.2 [ 4.1–6.6 ] ; moderate : 4.9 [ 3.8–6.1 ] ; both P < 0.01 ) compared with uninterrupted sitting ( 6.9 [ 5.5–8.7 ] ) . Insulin iAUC ( pmol/L ) ⋅ h was also reduced with both activity-break conditions ( light : 633.6 [ 552.4–727.1 ] ; moderate : 637.6 [ 555.5–731.9 ] , P < 0.0001 ) compared with uninterrupted sitting ( 828.6 [ 722.0–950.9 ] ) . CONCLUSIONS Interrupting sitting time with short bouts of light- or moderate-intensity walking  lowers postpr and ial glucose and insulin levels  in overweight/obese adults . This may improve glucose metabolism and potentially be an important public health and clinical intervention strategy for reducing cardiovascular risk Objectives Evaluate the predictive validity of ActiGraph energy expenditure equations and the classification accuracy of physical activity intensity cut-points in preschoolers . Methods Forty children aged 4–6 years ( 5.3±1.0 years ) completed a ∼150-min room calorimeter protocol involving age-appropriate sedentary , light and moderate-to vigorous-intensity physical activities . Children wore an ActiGraph GT3X on the right mid-axillary line of the hip . Energy expenditure measured by room calorimetry and physical activity intensity classified using direct observation were the criterion methods . Energy expenditure was predicted using Pate and Puyau equations . Physical activity intensity was classified using Evenson , Sirard , Van Cauwenberghe , Pate , Puyau , and Reilly , ActiGraph cut-points . Results The Pate equation significantly overestimated VO2 during sedentary behaviors , light physical activities and total VO2 ( P<0.001 ) . No difference was found between measured and predicted VO2 during moderate-to vigorous-intensity physical activities ( P = 0.072 ) . The Puyau equation significantly underestimated activity energy expenditure during moderate-to vigorous-intensity physical activities , light-intensity physical activities and total activity energy expenditure ( P<0.0125 ) . However , no overestimation of activity energy expenditure during sedentary behavior was found . The Evenson cut-point demonstrated significantly higher accuracy for classifying sedentary behaviors and light-intensity physical activities than others . Classification accuracy for moderate-to vigorous-intensity physical activities was significantly higher for Pate than others . Conclusion Available ActiGraph equations do not provide accurate estimates of energy expenditure across physical activity intensities in preschoolers . Cut-points of ≤25counts⋅15 s−1 and ≥420 counts⋅15 s−1 for classifying sedentary behaviors and moderate-to vigorous-intensity physical activities , respectively , are recommended Background Studies relating physical activity ( PA ) to  weight gain in children have produced mixed results , although there is some evidence for stronger associations with more intense physical activities . The present study tested the hypothesis that weight gain over one year in 8–10 year olds would be more strongly predicted by moderate and vigorous physical activity ( MVPA ) than total physical activity ( total PA ) or sedentary behaviour . Methodology Participants were 280 children taking part in the Physical Exercise and Appetite in Children Study ( PEACHES ) .  Weight status was assessed using body mass index ( BMI ) , fat mass index ( FMI ) , and waist circumference ( WC ) in school Year 4 ( baseline ; age 8.7 yrs ) and Year 5 ( follow-up ; age 9.7 yrs ) .  Physical activity  was measured at baseline using the Actigraph GT1 M accelerometer to assess total PA ( mean accelerometers counts per minute ) , MVPA ; ≥4000 counts per minute ) and sedentary time  ( < 100 counts per minute ) . Principal Findings After adjustment for baseline BMI , SES , sex and ethnicity , MVPA  was significantly associated with follow – up BMI ( adjusted β = −0.07 ; p = 0.002 ) . This association was independent of total PA or sedentary time  . Similar results were observed for FMI ; again MVPA was significantly associated with follow up FMI ( β = −0.16 ; p = 0.001 ) independent  of total PA or sedentary time . The pattern was similar for WC ( β = −0.07 ) , but the association between MVPA and WC did not reach significance at p = 0.06 . Conclusion The results of this study strongly support promotion of MVPA in children Background Physical activity ( PA ) is associated with positive cardio-metabolic health and emerging evidence suggests sedentary behavior ( SB ) may be detrimental to children 's health independent of PA . The primary aim of the Transform-Us ! study is to determine whether an 18-month , behavioral and environmental intervention in the school and family setting s results in higher levels of PA and lower rates of SB among 8 - 9 year old children compared with usual practice ( post-intervention and 12-months follow-up ) . The secondary aims are to determine the independent and combined effects of PA and SB on  children 's cardio-metabolic health risk factors ; identify the factors that mediate the success of the intervention ; and determine whether the intervention is cost-effective . Methods / design A four-arm cluster-r and omized controlled trial ( RCT ) with a 2 × 2 factorial design , with schools as the unit of r and omization . Twenty schools will be allocated to one of four intervention groups , sedentary behavior ( SB-I ) , physical activity ( PA-I ) , combined SB and PA ( SB+PA-I ) or current practice control ( C ) , which will be evaluated among approximately 600 children aged 8 - 9 years in school year 3 living in Melbourne , Australia . All children in year 3 at intervention schools in 2010 ( 8 - 9 years ) will receive the intervention over an 18-month period with a maintenance ' booster ' delivered in 2012 and children at all schools will be invited to participate in the evaluation assessment s. To maximize the sample and to capture new students arriving at intervention and control schools , recruitment will be on-going up to the post-intervention time point . Primary outcomes are time spent sitting and in PA assessed via accelerometers and inclinometers and survey . Discussion To our knowledge , Transform-Us ! is the first RCT to examine the effectiveness of intervention strategies for reducing children 's overall sedentary time , promoting PA and optimizing health outcomes . The integration of consistent strategies and messages to children from teachers and parents in both school and family setting s is a critical component of this study , and if shown to be effective , may have a significant impact on educational policies as well as on pedagogical and parenting practice s . Trial registration ACTRN12609000715279 ; Current Controlled Trials IS RCT OBJECTIVE To examine the prospect i ve association between objective ly measured time spent sedentary and insulin resistance and whether this association is independent of moderate- and vigorous-intensity physical activity ( MVPA ) and other relevant confounders . RESEARCH DESIGN AND METHODS This was a population -based study ( Medical Research Council Ely study ) in 376 middle-aged adults ( 166 men ; 210 women ) over 5.6 years of follow-up .  Physical activity and sedentary time were measured objective ly by individually calibrated minute-by-minute heart rate monitoring at both baseline and follow-up .  Sedentary time  was calculated as the heart rate observations ( in minutes ) below an individually predetermined threshold ( flex heart rate ) and expressed as a percentage of total monitored time during waking hours over 4 days . The percentage of time spent above 1.75 × resting heart rate represented MVPA . Fasting plasma insulin was used as a surrogate measure of insulin resistance . RESULTS Time spent sedentary  at baseline was significantly and positively associated with log fasting insulin at follow-up ( β = 0.003 , 95 % CI 0.0006–0.006 , P = 0.015 ) independent of baseline age , sex , fat mass , fasting insulin , smoking status , and follow-up time . After further adjustment for MVPA , this association was somewhat strengthened ( β = 0.004 , 95 % CI 0.0009–0.006 , P = 0.009 ) . CONCLUSIONS Time spent sedentary predicts higher levels of fasting insulin independent of the amount of time spent at moderate- and vigorous-intensity activity levels . This highlights the importance of reducing sedentary time in order to improve metabolic health , possibly in addition to the benefits associated with a physically active lifestyle 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 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 investigate the relationships between the time spent in specific intensities of activity and inactivity ,  cardiorespiratory fitness and body composition in children . Methods : A cross-sectional study was conducted in a r and om sample of schools . Height , weight and waist circumference were measured in 224 children aged 7–10 years . Cardiorespiratory fitness was estimated by the 20 m multistage running test , and physical activity was measured over 4 days by the RT3 ( a triaxial accelerometer ) . Time each day spent in moderate and vigorous intensities of activity was calculated . Results : Twelve schools agreed to participate in the study .  Body composition and fitness data were obtained for 224 children and activity data for 152 children . Boys were found to take part in about twice as much vigorous and hard activity as girls ( mean ( 95 % confidence interval ) 64.3 ( 53.2 to 75.4 ) min in boys compared with 37 ( 33.1 to 40.9 ) min in girls ; p<0.001 ) . In boys there was significant difference between those defined as normal , overweight and obese in the time spent in vigorous activity ( p<0.05 ) , but no such difference was found in girls . A significant negative correlation between waist circumference and time spent in vigorous activity ( r = –0.31 , p<0.05 ) was found in boys but not in girls . Time spent sedentary was positively correlated with waist circumference in boys ( r = 0.33 , p<0.01 ) but not in girls . In both boys and girls there were significant negative correlations between fitness and both body mass index ( r = –0.274 , p<0.001 ) and waist circumference ( boys : r = –0.503 , p<0.01 ; girls : r = –0.286 , p<0.01 ) . Conclusion : In boys , body composition was inversely related to fitness and to vigorous activity and was positively related to inactivity . In girls , body composition was related to fitness but not to specific components of physical activity The aim of this study is to examine  sedentary and light activity  in relation to overweight in adolescent girls . Adolescent girls were r and omly recruited from 36 schools participating in the Trial of Activity for Adolescent Girls ( TAAG ) . Assessment s included age , ethnicity , socioeconomic status , and body composition estimated from weight , height , and triceps skinfold .  Sedentary and light activity  was measured for 6 days using accelerometry in 6th and in 8th grade among two r and omly sample d cross-sections of girls .  Sedentary activity  increased from the 6th to 8th grade by 51.5 min/day . In the 8th grade , a significantly higher number of hours in sedentary activity for each of the 6-days of measurement were evident with higher tertiles of percent body fat ( 30 - 35 % , > 35 % fat ) ( P < 0.05 ) , but not across all increasing tertiles of BMI ( 5th to 85th , 85th to 95th , and > 95th percentiles ) . The increase in sedentary activity was observed on weekdays , but not on weekends for percent body fat tertiles . In the cohort of girls measured in both 6th and 8th grade s , the mean cross-sectional coefficient estimates were significant for percent body fat , but not BMI for sedentary and light activities . Adolescent girls from the 6th to 8th grade are shifting their time from light to more  sedentary activity as measured by accelerometers . In addition , the increase in sedentary activity is not associated with an adverse effect on BMI or percent body fat . The eventual impact of this shift to a more sedentary lifestyle on body composition and other outcomes needs to be evaluated further OBJECTIVE To report time and prevalence of leisure time sedentary and active behaviors in adolescents . METHOD Cross-sectional , stratified , r and om sample from schools in 14 districts in Scotl and , 2002 - 03 , using ecological momentary assessment ( n=385 boys , 606 girls ; mean age 14.1 years ; range 12.6 - 16.7 years ) . This is a method of capturing current behavioral episodes . We used 15 min time intervals . RESULTS  Television viewing  occupied the most leisure time . The five most time consuming sedentary activities occupied 228 min per weekday and 396 min per weekend day for boys , and 244 min per weekday and 400 min per weekend day for girls , with TV occupying one-third to one-half of this time . In contrast , 62 min was occupied by active transport and sports/exercise per weekday and 91 min per weekend day for boys , with 55 min per weekday and 47 min per weekend day for girls . A minority watched more than 4 h of TV per day , with more at weekends . Other main sedentary behaviors for boys were homework , playing computer/video games , and motorised transport and , for girls , homework , motorised transport , and sitting and talking . CONCLUSION Scottish adolescents engage in a variety of sedentary and active behaviors . Research into sedentary behavior must assess multiple behaviors and not rely solely on TV viewing 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 UNLABELLED The absence of comparative validity studies has prevented research ers from reaching consensus regarding the application of intensity-related accelerometer cut points for children and adolescents . PURPOSE This study aim ed to evaluate the classification accuracy of five sets of independently developed ActiGraph cut points using energy expenditure , measured by indirect calorimetry , as a criterion reference st and ard . METHODS A total of 206 participants between the ages of 5 and 15 yr completed 12 st and ardized activity trials . Trials consisted of sedentary activities ( lying down , writing , computer game ) , lifestyle activities ( sweeping , laundry , throw and catch , aerobics , basketball ) , and ambulatory activities ( comfortable walk , brisk walk , brisk treadmill walk , running ) . During each trial , participants wore an ActiGraph GT1 M , and V˙O2 was measured breath-by-breath using the Oxycon Mobile portable metabolic system . Physical activity intensity was estimated using five independently developed cut points : Freedson/Trost ( FT ) , Puyau ( PU ) , Treuth ( TR ) , Mattocks ( MT ) , and Evenson ( EV ) . Classification accuracy was evaluated via weighted κ statistics and area under the receiver operating characteristic curve ( ROC-AUC ) . RESULTS Across all four intensity levels , the EV ( κ=0.68 ) and FT ( κ=0.66 ) cut points exhibited significantly better agreement than TR ( κ=0.62 ) , MT ( κ=0.54 ) , and PU ( κ=0.36 ) . The EV and FT cut points exhibited significantly better classification accuracy for moderate- to vigorous-intensity physical activity ( ROC-AUC=0.90 ) than TR , PU , or MT cut points ( ROC-AUC=0.77 - 0.85 ) . Only the EV cut points provided acceptable classification accuracy for all four levels of physical activity intensity and performed well among children of all ages . The widely applied sedentary cut point of 100 counts per minute exhibited excellent classification accuracy ( ROC-AUC=0.90 ) . CONCLUSIONS On the basis of these findings , we recommend that research ers use the EV ActiGraph cut points to estimate time spent in sedentary , light- , moderate- , and vigorous-intensity activity in children and adolescents Childhood obesity is a public health concern with significant health and economic impacts . We conducted a prospect i ve experimental study in 4 classrooms in central Texas to determine the effect of desks that encourage st and ing rather than sitting on caloric expenditure in children . Students were monitored with  calorie expenditure-measuring arm-b and s worn for 10 days in the fall and spring . The treatment group experienced significant increases in calorie expenditure over the control group , a finding that has implication s for policy and practice
target: Based on 88 eligible observational studies , level of evidence grading and quantitative meta-analyses indicated that there is limited available evidence that the total volume or patterns of sedentary behaviour are associated with health in children and adolescents when accounting for moderate-intensity to vigorous-intensity physical activity or focusing on studies with low risk of bias .
  Quality evidence from studies with robust design s and methods , objective measures of sitting , examining associations for various health outcomes , is needed to better underst and if the overall volume or patterns of sedentary behaviour are independent determinants of health in children and adolescents
background: Sedentary behaviour has emerged as a unique determinant of health in adults .
  Studies in children and adolescents have been less consistent .
  We review ed the evidence to determine if the total volume and patterns ( i.e. breaks and bouts ) of objective ly measured sedentary  behaviour  were associated with adverse health outcomes in young people , independent of moderate-intensity to vigorous-intensity physical activity .