Ive used a kick bar in the parlour once or twice, they do work, but only in the restriction of their movment, they push into their groin and when they move their nerves get traped and hurt thus stops them wanting to

. I would never; use one out of pure choice! It was a herringbone pit parlour and its better than me having a few broken ribs, I didnt use it untl i was found unconciouse on the parlour floor one morning
Honest answer? Check if she has a problem that makes her do it first and foremost, udder issue, tender etc. If not and shes just that way, sell her on and get one that dosent.