There are a lot of videos of kids riding dogs in the wilds of the Internet. So many that if I wanted to comment on them all, it would be a full-time job - at least for the six hours I would last before tearing all my own hair out and running naked into the forest.
To preserve the already fragile remnants of my sanity, then, I’ve taken one compilation video as a representative sample of all the videos of kids sitting on the backs of dogs in the known universe.
This video is a reference guide of ways a dog can tell you it’s not feeling happy. Look at the fourth dog in the video, between 0:36 and 0:57. He’s pretty much the poster child for politely requesting you get the hell off. We see lip licking, “whale eye”, tight lips, yawning, looking at the handler, briefly licking the child - all classic stress signals in dogs. This handy poster by artist Lili Chin handily doubles as a Stressed Dog Bingo card. Unfortunately, the only prize is a bite in the face….
Physically, dogs have not evolved to cope with downwards pressure on their backs. Their muscles aren’t capable of withstanding the force of a giggling, wiggling, bouncing child; it can cause muscle pulls and tearing, leading to pain. Do this enough times, and you’ll give the dog back problems. It will be in constant pain. Try to sit a kid on a dog that you don’t know is in pain, and well, I’m sure you can guess how that might end up.
If there’s an instance of a human sitting astride a canine that isn’t covered in this video, it doesn’t matter. All possible dog-riding permutations are entirely, 100%, a Very Bad Idea.