Turns out, he can pull my big booty around on a scooter no problem!
Question: How often is it okay to work him like that? He pulled me for about 15-20 minutes today, no prob. Can he do that everyday? How long before I should up the weight? I want to eventually do weight pull with him, but have been going very slow, as I don't want to push him too hard or damage his joints. He's an incredibly laid-back lazy dog, but LOVES to pull, as we haven't been doing it, he's not been getting much in the way of exercise other than ripping around the yard with the girls, and the odd trip to the lake or river.
Gage is 55lbs, and just over a year old.

....how can you gage a dog with an itty bitty tongue?
)...you may want to look for a new vet if he thinks APBT should be 85lbs