METHODS The results of recent systematic review s are discussed and supplemented with relevant literature not included in these review s. PubMed was search ed for the years 2006 - 2011 for additional topics not sufficiently covered by the review s. RESULTS PA was associated with lower blood pressure and a healthier lipid blood profile in children .
The association was stronger when a composite risk factor score was analysed , and the associations between physical fitness and cardiovascular disease ( CVD ) risk factors were even stronger .
Muscle strength and endurance exercise each had an effect on blood lipids and insulin sensitivity even if the effect was smaller for muscle strength than for aerobic exercise .
New evidence suggests possible effects of PA  on C-reactive protein .
CONCLUSION There is accumulating evidence that PA can have beneficial effects on the risk factors of CVD in children .
BACKGROUND A number of recent systematic review s have result ed in changes in international recommendations for children 's participation in physical activity ( PA ) for health .
The World Health Authority ( WHO ) has recently released new recommendations .
The WHO still recommends 60 min of moderate to vigorous physical activity ( MVPA ) , but also emphasises that these minutes should be on top of everyday physical activities .
Everyday physical activities total around 30 min of MVPA in the quintile of the least active children , which means that the new recommendations constitute more activity in total compared with earlier recommendations .
OBJECTIVE To summarise evidence justifying new PA recommendation for cardiovascular health in children .
Effect of school based physical activity programme (KISS) on fitness and adiposity in primary schoolchildren: cluster randomised controlled trial
Objective To assess the effectiveness of a school based physical activity programme during one school year on physical and psychological health in young schoolchildren . Design Cluster r and omised controlled trial . Setting 28 classes from 15 elementary schools in Switzerl and r and omly selected and assigned in a 4:3 ratio to an intervention ( n=16 ) or control arm ( n=12 ) after stratification for grade ( first and fifth grade ) , from August 2005 to June 2006 . Participants 540 children , of whom 502 consented and presented at baseline . Intervention Children in the intervention arm ( n=297 ) received a multi-component physical activity programme that included structuring the three existing physical education lessons each week and adding two additional lessons a week , daily short activity breaks , and physical activity homework . Children ( n=205 ) and parents in the control group were not informed of an intervention group . For most outcome measures , the assessors were blinded . Main outcome measures Primary outcome measures included body fat ( sum of four skinfolds ) , aerobic fitness ( shuttle run test ) , physical activity ( accelerometry ) , and quality of life ( question naires ) . Secondary outcome measures included body mass index and cardiovascular risk score ( average z score of waist circumference , mean blood pressure , blood glucose , inverted high density lipoprotein cholesterol , and triglycerides ) . Results 498 children completed the baseline and follow-up assessment s ( mean age 6.9 ( SD 0.3 ) years for first grade , 11.1 ( 0.5 ) years for fifth grade ) . After adjustment for grade , sex , baseline values , and clustering within classes , children in the intervention arm compared with controls showed more negative changes in the z score of the sum of four skinfolds ( −0.12 , 95 % confidence interval −0.21 to −0.03 ; P=0.009 ) . Likewise , their z scores for aerobic fitness increased more favourably ( 0.17 , 0.01 to 0.32 ; P=0.04 ) , as did those for moderate-vigorous physical activity in school ( 1.19 , 0.78 to 1.60 ; P<0.001 ) , all day moderate-vigorous physical activity ( 0.44 , 0.05 to 0.82 ; P=0.03 ) , and total physical activity in school ( 0.92 , 0.35 to 1.50 ; P=0.003 ) . Z scores for overall daily physical activity ( 0.21 , −0.21 to 0.63 ) and physical quality of life ( 0.42 , −1.23 to 2.06 ) as well as psychological quality of life ( 0.59 , −0.85 to 2.03 ) did not change significantly . Conclusions A school based multi-component physical activity intervention including compulsory elements improved physical activity and fitness and reduced adiposity in children . Trial registration Current Controlled Trials IS RCT N15360785
METHODS The results of recent systematic review s are discussed and supplemented with relevant literature not included in these review s. PubMed was search ed for the years 2006 - 2011 for additional topics not sufficiently covered by the review s. RESULTS PA was associated with lower blood pressure and a healthier lipid blood profile in children .
The association was stronger when a composite risk factor score was analysed , and the associations between physical fitness and cardiovascular disease ( CVD ) risk factors were even stronger .
Muscle strength and endurance exercise each had an effect on blood lipids and insulin sensitivity even if the effect was smaller for muscle strength than for aerobic exercise .
New evidence suggests possible effects of PA  on C-reactive protein .
CONCLUSION There is accumulating evidence that PA can have beneficial effects on the risk factors of CVD in children .
BACKGROUND A number of recent systematic review s have result ed in changes in international recommendations for children 's participation in physical activity ( PA ) for health .
The World Health Authority ( WHO ) has recently released new recommendations .
The WHO still recommends 60 min of moderate to vigorous physical activity ( MVPA ) , but also emphasises that these minutes should be on top of everyday physical activities .
Everyday physical activities total around 30 min of MVPA in the quintile of the least active children , which means that the new recommendations constitute more activity in total compared with earlier recommendations .
OBJECTIVE To summarise evidence justifying new PA recommendation for cardiovascular health in children .