Parents who are active during pregnancy tend to raise more active children, finds a study published on bmj.com.
Children born in autumn are also more likely to be athletic, the findings suggest.
The researchers found that it wasn't biological factors at play that influenced a child's athleticism. Instead, the researchers said active pregnant women were likely to continue to exercise during their child's impressionable pre-school years. The example set by their parents influenced the children and encouraged them to get into the habit as well.
The researchers from Bristol University in England gathered data on 11- and 12-year-old children's activity over the course of at least three days. Each child was asked to wear an accelerometer for seven days, which recorded minute by minute the intensity and frequency of physical activity.
They analyzed the data against several factors, including how active mothers were during pregnancy. They found the children of those mothers who regularly exercised while pregnant ended up three to four per cent more active.
Another factor that influenced activity was season of birth. The authors say the association is difficult to explain, but may be linked to school starting age.
Children born in autumn tend to be the oldest in their classes and therefore the biggest and strongest. These advantages often lead to better performance in sports, providing children with more motivation to excel at it.
The authors recommend that future research should re-examine these associations in later adolescence, when physical activity declines, particularly among teen girls.
