The 5 minute rule isn't meant to be taken as law, more as a rule of thumb to provide a sensible guide of exercise rate, especially while they're building up muscle and so on.
Any working bred dog, particularly of gundog breeding is going to keep on running. And running and running some more. Young pups just love new experiences, and thrive on adrenaline. BUT they do not know when to stop. They need us to stop them.
It is far from obvious, even to those of us who have had quite a few puppies, when a pup hits the point of exhaustion - especially when they're interacting with other dogs. Their behaviour will be no different to how it was at the beginning of a walk; still full of beans.
The point is that once exhaustion is reached, not only is rational behaviour out of the window, but like children it's most likely when injuries occur.
Puppies don't get to dictate what they do here, they learn how to fit in with the household and what we think is best for them, and are as exhausted by a good 10/15 minute training session as they'd ever be by a half hour walk.
It's also worth noting that an adult dog will also run and run all day, and sometimes ours do, but realistically, few people have that much time available. They have to accept what we can give them to an extent and entertain themselves for the rest of the day. 2 or 3 hours a day is about all most of us can manage and that has to be enough.
I always try and keep the adult dog I'm trying to form in mind when I do anything with my pups. It helps with the end result
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