
Hi, I own Newfies and certainly wouldn't walk them for 25 minutes at that age(maybe I misread it??) I would limit to a 5 or 10 minute walk, then a play for 15 mins, increasing it weekly. By the age of 18months they are pretty much done and can cope with longer and longer walks. My two go out for a 4mile hike everyday(me in me scooter...a strange site I know!!! but I can't walk far and they love the pace at around 4mph...and boy does it condition them well!!) We walk around 2 miles, they have a play in the Park chasing frisbee, then 2 miles back. I would also be wary about unsupervised rough play...it only takes a minute for a jarring or bump to cause joint damage, maybe I'm over cautious though??? But then again I've never had a problem with any of my Giants! All the best, Dawn.