There is a large body of evidence from all study design s which suggests that decreasing any type of sedentary time is associated with lower health risk in youth aged 5 - 17 years .
In particular , the evidence suggests that daily TV viewing in excess of 2 hours is associated with reduced physical and psychosocial health , and that lowering sedentary time leads to reductions in BMI
Accumulating evidence suggests that , independent of physical activity levels , sedentary behaviours are associated with increased risk of cardio-metabolic disease , all-cause mortality , and a variety of physiological and psychological problems .
Therefore , the purpose of this systematic review is to determine the relationship between sedentary behaviour and health indicators in school-aged children and youth aged 5 - 17 years .
A longitudinal study of sedentary behavior and overweight in adolescent girls.
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
There is a large body of evidence from all study design s which suggests that decreasing any type of sedentary time is associated with lower health risk in youth aged 5 - 17 years .
In particular , the evidence suggests that daily TV viewing in excess of 2 hours is associated with reduced physical and psychosocial health , and that lowering sedentary time leads to reductions in BMI
Accumulating evidence suggests that , independent of physical activity levels , sedentary behaviours are associated with increased risk of cardio-metabolic disease , all-cause mortality , and a variety of physiological and psychological problems .
Therefore , the purpose of this systematic review is to determine the relationship between sedentary behaviour and health indicators in school-aged children and youth aged 5 - 17 years .