I've been around the USAR (Urban Search and Rescue, e.g., earthquake-collapsed structures) folks some. I'm thinking of maybe getting into a SAR dog program when I retire from being a paramedic/firefighter.
As someone who
was previously in pretty fair shape in the past (emphasis on the past tense), you might want to add a few miles a day to the sprinting (not jogging). That dog will work you to death in a urban setting. Be ready to start out as unskilled labor and work up to the team allowing you and a dog in. At least that is what I have always heard is the case.
Much Luck