When I go running with both my girls, The Princess always wants to get out and run at some point. My little Bean will get out and run a few steps, but she usually sticks pretty close to me. For her, it isn't about the running. She just wants to get out because her sister is out. And she half-heartedly runs because her sister is running. Then the other day, she randomly brought me her "running shoes" and put them to good use. (Don't mind the rest of her outfit. She got some big girl panties -sorry EMZ- that day and didn't want to wear anything over them. Luckily she was okay wearing her diaper under them.)
I like to run while The Princess is at preschool so I can run outside but only have to push the single jogger. My Bean loves our runs because she gets to hang out with Mom, eat snacks, watch movies on my iPod (and sometimes sleep). She never asks to get out; she just enjoys the ride.
(Wednesday's run. Calm, 40 degrees, snow flurries. Perfect.)