How long should a daily walk be for a 9 month old WL puppy?

[Tulip]

Starting Monday (Kody's in a kennel right now because my dad's away on a work trip) I'm going to start exercising my 9 month old puppy, Kody, more. On the weeks that I'm with my mom I'll only be able to walk him once a day and do one training session a day, so I was wondering how long each of these should be? I was planning on walking him around the neighborhood for a certain amount of time, then going to the neighborhood park, my backyard, and/or inside the house (depending on weather and where we are when it's been however long) to work on his obedience training. After that I'd sit in the family room with him and maybe watch an episode of something short like Scrubs (I'm a bit obsessed with Netflix) while playing with him, cuddling with him, or letting him chew on a bone or Kong, all depending on his energy level at that time.

So that's my basic plan. Sound good? Kody is an AKC, Working Line puppy with HIGH energy. The only time I've seen him tired out is when we get back from the dog park for a couple hours! The last time I weighed him he was 45 pounds, but it's been a couple months so I'm guessing he's around 55 now (mother was 65 and father was 75 or 80 I think). He eats a cup and a half in the morning and a cup and a half to two cups in the afternoon, plus an extra cup or so if we do some extra training. He seems to be at a good weight, but I'm always worried about him being too skinny. Do you think this is a good amount of food for him? Will I need to up it once I start walking him more?

And here's my main question: how long should the daily walk be? I've heard 40 minutes to an hour to two hours, and I was wondering what you guys think would be best for Kody based on his genetics, energy level, weight, and age. I also have asthma, so it's hard for me to exercise for too long, but I do have an inhaler, which helps some. Thanks for reading this super long post!!!

[onyx'girl]

I would use his meals to hunt for his food or track him with it, it will wear him out mentally...higher drive WL's need mental exercise as well as physical.

What surfaces are you walking? If it is pavement, I'd change it up to sand/grass/hills etc.

Really, mental exercise will rock his world...obedience/tug/ obedience/perchwork(rear end awareness). I'd spend more time on that then going for walks to try to drain his energy.

[Cassidy's Mom]

There really is no set amount. I don't actually take my dogs for daily walks, and never have. But when I do take a dog out for a leash walk, it's always a training walk, not just for exercise. I was doing that with Halo several times a week, for 3 or 4 miles each time starting at about 7 months old. We worked on leash skills, I reinforced eye contact, we did lots of sits and downs and stays, short recalls, all kinds of things. All of that worked her brain much more than the walk worked her body.

[Tulip]

He hasn't been getting the physical exercise he needs, unfortunately (bad on me! I feel bad about it and am trying to fix it now!), so I definitely need to focus on getting this need met with a nice long walk.

I am walking pavement, but there isn't much choice when you have a limited amount of time and can't drive. I could probably do some grass sometimes in the neighborhood park and this meadow behind the creek which is behind the park though. I have started tracking him a couple times, but again, hard to do when all you have is the backyard or a place with tons of people and dog scents, a limited amount of time, and no drivers license or car.

I was also planning on making them training walks; practicing fus (heel), achtung (watch me), etc.