Why not just play a game of fetch in the backyard for 10 minutes before trying to attempt a walk??
I often do this with young dogs that I board. I thow the ball around so they can get their energy out and then we go for an onleash walk. I found if I did not do this...the dogs kept pulling and or jumping up on me. My elbows and arms are paying for all of the years of walking dogs onleash.
Gina