According to the DailyNews:
"Women who exercise during pregnancy could help their babies turn into sporty adults, a study has found. A love of fitness starts in the womb - when set a good example by mothers - researchers discovered."
I'm pretty sure that this is due to epigenetic influences.
ep·i·ge·net·ics
ˌepəjəˈnediks/
noun
BIOLOGY
the study of changes in organisms caused by modification of gene expression rather than alteration of the genetic code itself.
Part of the reason I've never had kids is I want to wait until I'm living the type of life and I'm being the type of person that I've always wanted to be, so I can be the type of father I've always wanted to have.
I simply do not want to pass on any of my bad habits to my future kids.
Epigenetic's is is a a field we're just starting to understand, but even though this is based on rodent studies...I would say the mother's habits caused epigenetic changes that made the babies love exercising. It could be the endorphins released during exercise "turned on" those genes in the baby, so they loved exercise induced endorphin release.
This is fascinating stuff.
KB