I found this drawing and followed the belt with my finger. Turn the crank and a shoe swings round to kick you in the backside. Joe W. Armstrong patented the machine in 2001. My favourite part is tucked away in the description. Once you’ve had enough, the whole thing folds up for storage.

I had to follow the belt in this drawing to see what the crank did. Turn it and a shoe swings round to kick you in the backside. Joe W. Armstrong got the patent in 2001. My favourite detail is in the small print. The whole thing folds away for storage.