TY  - JOUR
PY  - 2015//
TI  - Are children's activity levels determined by their genes or environment? A systematic review of twin studies
JO  - Preventive medicine reports
A1  - Fisher, Abigail
A1  - Smith, Lee
A1  - van Jaarsveld, Cornelia H. M.
A1  - Sawyer, Alexia
A1  - Wardle, Jane
SP  - 548
EP  - 553
VL  - 2
IS  - 
N2  - CONTEXT   The importance of physical activity to paediatric health warrants investigation into its determinants. <br><br>OBJECTIVE measurement allows a robust examination of genetic and environmental influences on physical activity. <br><br>OBJECTIVE  To systematically review the evidence on the extent of genetic and environmental influence on children's objectively-measured activity levels from twin studies. Data sources and search terms  Medline, EMBASE, PsycINFO, Health and Psychosocial Instruments and all Ovid Databases. Search terms: "accelerometer" OR "actometer" OR "motion sensor" OR "heart rate monitor" OR "physical activity energy expenditure" AND "twin". Limited to Human, English language and children (0-18 years). <br><br>RESULTS  Seven sets of analyses were included in the review. Six analyses examined children's daily-life activity and found that the shared environment had a strong influence on activity levels (weighted mean 60%), with a smaller contribution from genetic factors (weighted mean 21%). Two analyses examined short-term, self-directed activity in a standard environment and found a smaller shared environment effect (weighted mean 25%) and a larger genetic estimate (weighted mean 45%). <br><br>CONCLUSIONS  Although genetic influences may be expressed when children have brief opportunities for autonomous activity, activity levels in daily-life are predominantly explained by environmental factors. Future research should aim to identify key environmental drivers of childhood activity.<p />  <p>Language: en</p>
LA  - en
SN  - 2211-3355
UR  - http://dx.doi.org/10.1016/j.pmedr.2015.06.011
ID  - ref1
ER  -