I agree, the walk will do it. But that thing about pooping an hour after eating doesn't seem to work with ours. She is fed in the morning and at night. She will poop in the morning sometime before I go to work (not an hour after eating), and she usually poops when I get home from work (usually an hour or so before dinner). She is pretty regular. You might what to see what the schedule is (feeding time) and when she usually poops, and take her out when she usually goes. I think I am more trained than our baby is, and she is nearly 7 y/o. But she pretty much is on a schedule that she set herself, and I follow.
