Scott, if your Heeler is anything like my sister's Blue Heeler/Border Collie cross, you will have to be the one to stop when you feel the dog has had enough. Don't over do hard exercise, such as jogging or running especially on concrete at least until he matures at around 1 1/2 to 2 years of age.
Be sure and give him jobs to do such as obedience exercises, nilif, and anythin you can think of to teach him. If you don't, he'll figure out jobs for himself and you probably won't like the ones he makes up for himself.
