Our daughter (mild autism) did "hippotherapy" weekly when she was in elementary school (about 20 years ago). It was partly because she was obsessed with horses. But I think it helped strengthen her core muscles and stimulated her vestibular system. She was also extremely fond of swings and rocking. In "The Out-of-Synch Child," the author explains that the vestibular system is linked to verbal communication, so it may have helped her speech-wise, too. It's not just riding horse back, though. There's brushing the horse and cleaning the hooves, too.

I write in a vague way ("I think it helped" and "it may have helped") because my wife and I had her in many programs, and we were giving her vitamin supplements all at once.

I rode a horse on a trail once. I loved the gentle swaying sensation of movement. And it was a chilly day, but the horse was warm beneath me.

What are you hoping to achieve, @Boringmom?