Conclusions Multicomponent interventions which also include the use of st and ing desks may be an effective method for reducing  children 's sedentary time  in a school-based intervention .
Introduction Prolonged , uninterrupted periods of sedentary time may be associated with increased risk of Type II diabetes , cardiovascular disease and all-cause mortality even if the minimum recommended levels of daily physical activity are achieved .
It is reported that children spend approximately 80 % of their day engaged in sedentary behaviours .
Since children spend a large portion of their waking time at school , school-based interventions targeting excessive or interrupted periods of sedentary time have been investigated in a number of studies .
However , results of the effectiveness of studies to- date have been inconsistent .
Aim To conduct a systematic review to evaluate the effectiveness of school-based interventions design ed to reduce sedentary behaviour on objective ly measured sedentary time in children .
Promoting healthy weight in primary school children through physical activity and nutrition education: a pragmatic evaluation of the CHANGE! randomised intervention study
Background This pragmatic evaluation investigated the effectiveness of the Children ’s Health , Activity and Nutrition : Get Educated ! ( CHANGE ! ) Project , a cluster r and omised intervention to promote healthy weight using an educational focus on physical activity and healthy eating . Methods Participants ( n = 318 , aged 10–11 years ) from 6 Intervention and 6 Comparison schools took part in the 20 weeks intervention between November 2010 and March/April 2011 . This consisted of a teacher-led curriculum , learning re sources , and homework tasks . Primary outcome measures were waist circumference , body mass index ( BMI ) , and BMI z-scores . Secondary outcomes were objective ly-assessed physical activity and sedentary time , and food intake . Outcomes were assessed at baseline , at post-intervention ( 20 weeks ) , and at follow-up ( 30 weeks ) . Data were analysed using 2-level multi-level modelling ( levels : school , student ) and adjusted for baseline values of the outcomes and potential confounders . Differences in intervention effect by subgroup ( sex , weight status , socio-economic status ) were explored using statistical interaction . Results Significant between-group effects were observed for waist circumference at post-intervention ( β for intervention effect = −1.63 ( 95 % CI = −2.20 , -1.07 ) cm , p<0.001 ) and for BMI z-score at follow-up ( β=−0.24 ( 95 % CI = −0.48 , -0.003 ) , p=0.04 ) . At follow-up there was also a significant intervention effect for light intensity physical activity ( β=25.97 ( 95 % CI = 8.04 , 43.89 ) min , p=0.01 ) . Interaction analyses revealed that the intervention was most effective for overweight/obese participants ( waist circumference : β=−2.82 ( 95 % CI = −4.06 , -1.58 ) cm , p<0.001 ) , girls ( BMI : β=−0.39 ( 95 % CI = −0.81 , 0.03 ) kg/m2 , p=0.07 ) , and participants with higher family socioeconomic status ( breakfast consumption : β=8.82 ( 95 % CI = 6.47 , 11.16 ) , p=0.07 ) . Conclusions The CHANGE ! intervention positively influenced body size outcomes and light physical activity , and most effectively influenced body size outcomes among overweight and obese children and girls . The findings add support for the effectiveness of combined school-based physical activity and nutrition interventions . Additional work is required to test intervention fidelity and the sustained effectiveness of this intervention in the medium and long term . Trial registration Current Controlled Trials IS RCT N03863885
Conclusions Multicomponent interventions which also include the use of st and ing desks may be an effective method for reducing  children 's sedentary time  in a school-based intervention .
Introduction Prolonged , uninterrupted periods of sedentary time may be associated with increased risk of Type II diabetes , cardiovascular disease and all-cause mortality even if the minimum recommended levels of daily physical activity are achieved .
It is reported that children spend approximately 80 % of their day engaged in sedentary behaviours .
Since children spend a large portion of their waking time at school , school-based interventions targeting excessive or interrupted periods of sedentary time have been investigated in a number of studies .
However , results of the effectiveness of studies to- date have been inconsistent .
Aim To conduct a systematic review to evaluate the effectiveness of school-based interventions design ed to reduce sedentary behaviour on objective ly measured sedentary time in children .