Question: 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?](https://pets.stackexchange.com/questions/141/what-can-i-do-if-my-puppy-is-hyperactive?lq=1) 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.

Answer: 
Good morning! Your puppy is probably sizable and physically immature, so his joints are not really ready for a lot of intense road work. Your veterinarian can probably guide you on this, as your dogs’ conditioning needs to be done carefully. For instance, an overweight dog would probably do well to lose some of the weight prior to pounding the pavement.

The duration on these walks may need to be shorter, initially. Intermittently rewarding your pup for calmly walking in a loose lead position will probably enable you to minimize tugging on the lead - the tugging could spark off some of the “manic” behavior.

Keep it light and easy, with a lot of positive reinforcement, and I suspect you’ll see rapid improvement.
I have a Siberian Husky that is not much older than your dog. As I take him for a jog/walk, he will do the same thing sometimes such as bite the leash or jump around. 

It could very well be the case that your dog is bored of walking and wants to run or at least go faster. This makes sense for a Husky Shepherd. They have lots of energy and your goal should be to help them exert it.