The Horse Physio - Delivering care with expertise since 1992

8.12.2022 Is it a u shaped or an n shaped buck?

Have you ever sat on a horse that has bucked? Have you ever been bucked off? I bet there’s not many riders this hasn’t happened to at some point! I’ve been riding since I was three years old and I know I’ve come off many times. Some of them were pure accidents, some of them, pure stupidity, and many of them, a misunderstanding of what my horse was trying to tell me, no doubt.

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I heard a description that really resonated me, when I was listening to Horse and Hound podcast number 130, where Dr Gemma Pearson talked about the difference between an N shaped buck and a U-shaped buck. She said, and I agree with her, that an N shaped back is invariably pain related, whereas there can be a variety of reasons for a U-shaped buck. The vast majority of causes for a U-shaped buck are still pain related, but it’s a possibility that there could be at least a behavioural element in there in some cases.

The N shaped buck that most comes to mind for me is the horse who is cold backed, girthy, or whatever description you want to use of the discomfort and resistance a horse shows when the saddle is put on, when the girth is done up, or when he takes his first steps with or without a rider. Many of us will be familiar with the feeling or sight of a horse lifting his back as the rider gets on. It’s usually accompanied by a change in the horse’s facial expression (and in the rider’s facial expression, if they’re aware of what’s going on!), and obvious tension in the horse.

A video I watched of a horse for sale clearly showed this behaviour at the mounting block. It was preceded by the horse putting his ears back, chomping at the bit, and swishing his tail as he was led towards the mounting block. These signs told me clearly that he was not looking forward to the rider getting on board. The video continued to show his ridden work in walk, trot and canter, where there was frequent tail swishing, ears back, toe dragging, head above the vertical, a reluctance to move forwards, and resistance to the contact. I’m guessing that the sales person who posted that video has not come across the Ridden Horse Ethogram (Ridden Horse Performance Checklist).

You, of course, do you have an awareness of the Ridden Horse Ethogram. This is a list of 24 behaviours, the presence of eight or more of which suggests that the horse is experiencing musculoskeletal pain. Have a flick through some videos of horses for sale, and see how many of the behaviours you can pick up. It’s an interesting exercise!

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Keep an eye out for my next book, “Harmonious Horsemanship: How to use the Ridden Horse Ethogram to Optimise Potential, Partnership, and Performance”. This ground-breaking book is co-authored with Dr Sue Dyson, and will be available summer 2023. Sign up at to be kept up to date with new information as it comes available. Watch a FREE 30-minute documentary on the Ridden Horse Ethogram here.

Here’s a FREE 30-minute presentation by Sue Palmer on how to be confident that your horse is comfortable.

Other books by Sue Palmer M.Sc. MCSP:

‘Horse Massage for Horse Owners’

‘Understanding Horse Performance: Brain, Pain or Training?’

© Sue Palmer, The Horse Physio, 2022

December 8, 2022
Sue Palmer