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
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 .
Time spent in sedentary behavior and changes in childhood BMI: a longitudinal study from ages 9 to 15 years
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
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
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 .