I think Fox has a Personal Trainer.

He has known Xylophone, I would say 18 years.  Julie got him right around the same time my parents bought Fox.  They've been pastured together for at least 8 years now...so they know each other pretty well.

I don't know what it is that drives Xylophone...maybe it's a way of forcing them both to exercise....like a horse version of Mall Walking...But regularly you can see him casually walking fox up and down the hills of their pasture.  It's very Mid afternoon Stroll-ish. 

I don't know if Fox enjoys it, but I am grateful that Xy forces him to move around the way that he does.  His hocks need it.

I like to think he does it out of love.