if its like the ones ive seen at shows i cant see how a dog would benefit or would get fit from doing that, i would think they would end up with strains,
but using it over a 150 yrds of straight running it could help.
when i used to walk whippets out when i was younger the bloke who owned them used a starter moter off a car, connected to an old bike wheel,
but having a muscled dog, it looks good on the show ground, but in the field they will tire alot quicker than a properly conditioned dog.
take atheletes , sprinters look good but after each race they are fecked and they can barley mana