So I took my rescued 2yr old German shepherd on a run for the first time. He did great the first 3/4 of a mile or so then I was pretty much pulling him the rest of the way. I thought he would be pulling me but not the case. Any ideas as to why he didn't run and run and run.
Will he retrieve a ball? Assuming he has no health problems and may have had a previous life of no real exercise conditioning is everything. Short wind sprints chasing a ball on a soft surface will help to strengthen him. If he quits let him relax. Be careful not to over heat him. It won't take to long before you can't throw the ball enough. Will he swim? Another best conditioning exercise.
He isn't up to it. He has to build up the stamina. Maybe he just doesn't like running, mine doesn't but he can herd sheep at an even pace all day. Don't push him- there's a reason he didn't run and run and run