I don't see any relation between a horse and a unicycle
On horseback on mountain paths you have to lean forward/backward to keep your balance and to avoid getting thrown down and i thought the something like that might be the case here.. anyways you've got me hooked on to this. I've been watching too many videos. only there doesn't seem to be any unicycles around where i live. So will have to wait before i can try or perhaps build one.
cheers,
Pracas