I do the same with my dog.  I usually chase him around the house/yard/park/trails/etc.  He gets super excited when I take out the bicycle, he loves running next to that thing.  Sneaky little booger will even sneak up behind me in the garage and bark at my butt then do the "come chase me!" thing. I can't imagine the insufferable torture of not being able to give chase, let alone by choice from being fat.  And yelling at its own kids as if it was their fault piggy is so fat she can't play with them!