Highly intelligent working breed dogs need a lot of mental exercise! Physical exercise is needed as well, of course, but I find that giving my dogs fun challenging mental workouts makes them happy, calm, tired, and less prone to getting into mischief.
I work with my dogs practicing lots of tricks, lessons, etc to tire them out. I use praise and food rewards and fun... and always make them happy sessions. After a good mental workout they are pooped and plop lazily on the couch or their doggie bed
I kinda equate it with a hard day at school or work. You may not have physically worked hard, but if you used your brain a lot to think all day, you are probably going to go home tired!!
Also we put up a homemade flirt pole in our backyard to tire Puma pup out and to teach her impulse control and how to share her toys with us. Works like a charm! Roughly 15 minutes of all that jumping and waiting for her release cues and she is pooped out.
Also if the weather permits, I use a hose with Puma pup and have her "chase" the water. She absolutely loves it. She will run from side to side of our yard trying to bite at the water. So fun!!!!
Also we play "soccer" in the yard with a hard plastic sound ball. (Got it at Ross for about $10) She loves that, too and it totally tires her out. Plus again, teaches her to wait, share toys, etc.
Walking/running is good, but vary it up and you both may have more fun!
A tired dog is a good dog