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 .
Sedentariness, small-screen recreation, and fitness in youth.
BACKGROUND There are concerns that sedentariness among young people has increased and that this may be detrimental to their health . The purpose of this study was to examine the association between sedentary activities , including  small-screen recreation ( SSR : watching TV/DVDs/videos , recreational computer use ) and cardiorespiratory endurance ( CRE ) in children aged 11 - 15 years . METHODS A cross-sectional representative population survey was taken of New South Wales ( Australia ) school students in Grade s 6 , 8 , and 10 ( N=2750 ) in 2004 .  Sedentary activities and SSR were measured by a self-report question naire .  CRE was determined by the 20-meter multi-stage shuttle run test . The optimal cut point for time spent on SSR was determined by receiver operating characteristic analysis . RESULTS Time spent in sedentary activities was inversely associated with CRE among Grade 8 students ( p=0.01 ) and Grade 10 girls ( p=0.03 ) . CRE was lower among Grade 8 students ( p<0.001 ) and Grade 10 girls ( p<0.001 ) who spent > or=2 hours/day on SSR compared with students who spent < 2 hours/day . The 2-hour/day cut point for SSR had high sensitivity ( boys : 84 % , [ 95 % CI=79 % , 87 % ] ; girls : 79 % [ 95 % CI=74 % , 84 % ] ) and low specificity ( boys : 28 % [ 95 % CI=24 % , 32 % ] ; girls : 42 % [ 95 % CI=38 % , 46 % ] ) . CONCLUSIONS Cardiorespiratory endurance did not differ consistently across quintiles of sedentariness and SSR among boys ; however , among girls there was a consistent inverse association . If confirmed in prospect i ve studies , these findings have important implication s for risk of chronic disease
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 .