I don't have a BC, but something v. similar - an Aussie shepherd... he is not the most active, but certianly active enough!!!! If i'm doing nothing, he'll do nothing, but if i'm doing something that involves moving around - he's in for it!!! At the moment, due to the way our club is structured (not allowed to do any agility, flyball until get basic obedience title - around 14mths) we are only doing obedience and just started agility (another club - Leo is about to have his test soon). When we get started I think he'll move like a rocket in agility as he loves it - won't stop barking.... BTW anyone know how to stop that???? He knows what quiet means... Later on, when he is older we'll do some flyball and maybe herding, but i've heard it is quite expensive (lol - 'scuse the pun!!).
hope that helps