Our puppy (8 months old, Husky/Shepherd mix) is getting to be good enough on the leash that I can take him for a nice run. I live near a park with a 5K loop road, which I used to run regularly.
When I first started taking him out around the loop road, he'd jump at me and bite and try to get me to play right away, or at least at fairly arbitrary intervals. I got a good lesson in dominant walking, and a better slip lead that actually loosens again after I tug it so I can keep it high on his neck, give it a quick tug and re-orient him to following me and we can keep going. That had a huge impact--he's way, way more manageable. My pace is pretty slow, he seems to handle it very comfortably, and we stop for water.
But since the walking lesson I've noticed that about 2/3 to 3/4 of the way through, he still gets really unmanageable. He tries to jump on me and bite playfully, but he forgets his bite inhibition entirely. The other day he did this really manic digging for a few minutes. Just scraping at the soil with dirt flying and shaking his head and jumping around. In general, it seems like he just gets manic and bonkers, jumping around and barking at me.
It occurred to me (this might be obvious to everyone else?) that 5K might just be too long for him to run. Do I need to find a shorter route, or is there something else going on?
P.S. There's a mention of overtiredness at What can I do if my puppy is hyperactive? which seems to suggest that's exactly what is going on. But I'd love to know more about how to tell when a young dog is getting overtired.