Riders take load off horses

May 01, 2013

Horses experience back pain so riders do their best to minimise the loads exerted on horses' backs, but how much of a difference do the different trotting techniques make to the loads horses experience? Patricia de Cocq from Wageningen University analysed riders on trotting horses and discovered that 'rising trot' reduces the load significantly. She also built a computational simulation of a horse and rider that explains why jockeys ride so fast.

Patricia de Cocq is a keen horsewoman, but her interest in extends beyond her passion for riding: she is also a vet. Interested in the animals' , de Cocq explains that many horses that are ridden experience back pain that is hard to treat. Which made her wonder: could riders modify their technique to reduce the load exerted on their horses' backs? Analysing the movements of riders on trotting horses, de Cocq discovered that 'rising trot' significantly reduces the load exerted on horses' backs. She also built a computational simulation of a horse and rider that could help riders discover better ways of riding and publishes her discovery that jockeys ride fast because their centre of mass barely moves at all in The Journal of Experimental Biology.

According to de Cocq, from Wageningen University, The Netherlands, riders have a choice of two techniques when perched on a trotting horse: the easier 'rising trot' – when the rider bobs up and down, standing in the stirrups when off the saddle – and the more technically challenging 'sitting trot', where the rider remains firmly seated. As rising trot was thought to reduce the load exerted on a trotting horse's back, de Cocq travelled to Hilary Clayton's lab at Michigan State University, USA, to use Clayton's state-of-the-art 3D equipment to test the theory. By filming experienced dressage riders as they trotted using both techniques and analysing the motion of each horse and rider, de Cocq could see that the centre of mass of riders using rising trot moved much less during the standing phase than the centre of mass of sitting trot , reducing the force exerted on the horse's back and lessening the chance of injury.

However, while de Cocq was analysing the data, she came across a paper in Science (Pfau et al., Science, 325, 289) that explained how the technique used by modern jockeys – where they stand in their stirrups – had significantly improved times in horse racing. de Cocq noticed that jockeys' posture was similar to the standing phase of the rising trot. She wondered whether she could build a mathematical model of a horse and rider that would simulate the movement of a rider's centre of mass and identify factors that could reduce the force exerted by the rider on a horse's back.

Teaming up with Mees Muller and Johan van Leeuwen, de Cocq built three increasingly sophisticated models, representing the horse and rider as systems of springs, dampers and point masses. Then, by varying the stiffness of the spring representing the rider in the simplest model, de Cocq successfully reproduced the motion of the rider's centre of mass during sitting trot and when using the jockey's standing posture. Then, when she repeated the calculations using the second model where she added a damper and brief free-fall to the first model, the motion of the centre of mass of the sitting trot rider and the jockey was even more lifelike. But neither model reproduced the motion of a rider's centre of mass during rising trot until de Cocq and van Leeuwen added a second spring – mimicking the rider's leg during the standing portion of the stride – to the simulated rider spring. By alternating between the two springs – activating the leg spring during the standing portion of the stride and the rider spring during the seated portion – de Cocq successfully simulated the rising trot.

de Cocq's calculations also showed how difficult the jockey's technique is. She could only simulate the relatively smooth motion of the jockey's centre of mass using a narrow range of spring stiffnesses and damping; and only one combination of spring stiffness and damping produced the optimal situation where the jockey's centre of mass followed an almost flat line. de Cocq points out that the current technique used by jockeys allows horses to gallop faster than other techniques. However, it requires a huge amount of strength and training and she says, 'If jockeys want to improve even more they would need to go in a straight line, not move up and down, and that would be a challenge.'

Explore further: Researchers use gait primitives from real animals to simulate movement in robots (w/ video)

More information: de Cocq, P., Muller, M., Clayton, H. M. and van Leeuwen, J. L. (2013). Modelling biomechanical requirements of a rider for different horse-riding techniques at trot. J. Exp. Biol. 216, 1850-1861. jeb.biologists.org/content/216/10/1850.abstract

add to favorites email to friend print save as pdf

Related Stories

Special horseshoes measure acceleration in horses

Jul 07, 2008

The most frequent injuries that horses suffer are derived from pressure exerted by riders, and knowing which forces are involved when horses move can prove highly informative when considering treatment for such injuries.

Horses don't have stage fright—but their riders do

Feb 19, 2013

(Phys.org)—It is well known that horses show symptoms of stress when ridden but relatively little attention has been paid to the effects on their riders. This is surprising, as equestrian sports rely on ...

How good are your horse's brakes?

Jan 04, 2012

Horseriding is a popular summer holiday activity, but few people know that horses kill more Australians annually than any other animal. Professor Paul McGreevy, from the University of Sydney's Faculty of Veterinary ...

Recommended for you

Male monkey filmed caring for dying mate (w/ Video)

Apr 18, 2014

(Phys.org) —The incident was captured by Dr Bruna Bezerra and colleagues in the Atlantic Forest in the Northeast of Brazil.  Dr Bezerra is a Research Associate at the University of Bristol and a Professor ...

Orchid named after UC Riverside researcher

Apr 17, 2014

One day about eight years ago, Katia Silvera, a postdoctoral scholar at the University of California, Riverside, and her father were on a field trip in a mountainous area in central Panama when they stumbled ...

In sex-reversed cave insects, females have the penises

Apr 17, 2014

Researchers reporting in the Cell Press journal Current Biology on April 17 have discovered little-known cave insects with rather novel sex lives. The Brazilian insects, which represent four distinct but re ...

Fear of the cuckoo mafia

Apr 17, 2014

If a restaurant owner fails to pay the protection money demanded of him, he can expect his premises to be trashed. Warnings like these are seldom required, however, as fear of the consequences is enough to ...

User comments : 0

More news stories

Biologists help solve fungi mysteries

(Phys.org) —A new genetic analysis revealing the previously unknown biodiversity and distribution of thousands of fungi in North America might also reveal a previously underappreciated contributor to climate ...

Researchers successfully clone adult human stem cells

(Phys.org) —An international team of researchers, led by Robert Lanza, of Advanced Cell Technology, has announced that they have performed the first successful cloning of adult human skin cells into stem ...

NASA's space station Robonaut finally getting legs

Robonaut, the first out-of-this-world humanoid, is finally getting its space legs. For three years, Robonaut has had to manage from the waist up. This new pair of legs means the experimental robot—now stuck ...

Ex-Apple chief plans mobile phone for India

Former Apple chief executive John Sculley, whose marketing skills helped bring the personal computer to desktops worldwide, says he plans to launch a mobile phone in India to exploit its still largely untapped ...

Filipino tests negative for Middle East virus

A Filipino nurse who tested positive for the Middle East virus has been found free of infection in a subsequent examination after he returned home, Philippine health officials said Saturday.

Egypt archaeologists find ancient writer's tomb

Egypt's minister of antiquities says a team of Spanish archaeologists has discovered two tombs in the southern part of the country, one of them belonging to a writer and containing a trove of artifacts including reed pens ...

Airbnb rental site raises $450 mn

Online lodging listings website Airbnb inked a $450 million funding deal with investors led by TPG, a source close to the matter said Friday.