My two boys are funny. I take them outside and the Lhasa (Zeke, who is a couch potato) will know when Baxter gets into the zoomie mode, so he will just stand still for maybe 10 minutes. The whole time Baxter is running around the yard doing a huffing noise, and will dive bomb poor Zeke. He will do this 30 or 40 times, hopping over Zeke, butting him in the bum or just annoying him. And he is sooooo persistant in doing this. He will keep it up until zeke gives a quick bark, and walks away.