When the boy and I go out for a walk, we sometimes challenge each other to walk in different ways. It makes it a bit more fun, and if we're dawdling, or getting late, then I can encourage him to run. The downside of course is that I have to do it as well. The boy loves it though, because he's all about "getting exercise, because exercise is good for us".
As we were out today, I'm sure I was giving my neighbours a good laugh as we walked along. Some of the ways the boy made me walk were to run like cheetah, stomp like dino, hop like bunny, jump like kangaroo, march like soldier, and gallop like horse. My personal favourite was to tiptoe like ballerina, including having to hold our arms up above our head, because "Mummy, that's what ballerinas do". Although maybe we haven't reached the peak of silliness until we have to walk like an Egyptian.