I've got 2 dogs, both pretty large 70 and 85lbs respectively. They both do about the same amount of activity. The 85lb one is a bit younger so definitely does a little more, but probably not enough to really make a difference.

His nails however need to be trimmed manually, they do not get ground down from just walking/running nor the general lunacy that is being a husky mix.

However the other pup, thats a some type of pit-lab mix, I've not once had to trim her nails in the 9 years I've had her.

I'm not 100% sure why, but I can tell you my husky mix's nails are alot thicker than my pit even when considering proportionally to the size of the dog.