The Cost of Transport in an Extended Trot

This is a more in depth commentary on my original blog post The Big Trot in relation to the Endurance Horse.

A study:
S. J. WICKLER, D. F. HOYT*, E.A. COGGER and R. MCGUIRE
Equine Research Center and Departments of Animal and Veterinary Science and *Biological Sciences,
California State Polytechnic University, Pomona, California 91768, USA.

The thesis of the paper was done with a core group of Arabians and Hackneys, discussing the metabolic costs of an extended trot. The paper does take a bit of reading, but is most certainly worth the time.

While it doesn't address my opinion of correct carriage of a horse during an extended trot, - it does however present a fairly clear case arguing against the 14 mph/trot - in that the horses are by this point ineffecient in relation to their requirements for oxygen intake and energy output - as well as a discussion of stride length vs speed and the ensuing concussive forces.

Part of the study also takes into consideration the trot-gallop transitions. It appears that the majority of the horses preferred to move from the trot into the gallop(or canter) at a trot speed that was not equivalent to the equal speed in the canter - regardless of whether the study horse was a bred trotter, or a horse trained to use an extended gait.

When the horse was allowed to move into a canter, the cost of transport lowered accordingly- furthering the argument that while the BIG trot is a preferred gait of endurance riders - it is not a preferred gait of the horses- who seem to recognize that when the demand for speed is increased, metabolically they intuitively discard the trot in favor of a more energy saving gait.

The study in complete can be read here:
**scroll down to the bottom of the page to find the view/download link for the entire paper**

The Big Trot

Nothing says endurance like a line of horses moving down the trail with that big extended trot that is the face of the sport as we know it. But just how good is this gait. In my opinion, not so great.
I'm not saying I have no intention of ever putting my endurance horse into an extended trot- but lets consider how hard a typical horse works. The reason I specify typical, is because most (not all) but most endurance horses have a specific 'look' when they get into this trot.
Usually what you see, is a head high, hollow back, big front end swinging trot. This unfortunately doesn't bode well for your horses muscle structure, or energy efficiency.

Muscle issues:
Hyper extension. When moving into this typoe of trot, essentially what your horse is doing, is hyper extending their body to trot BIG. Now consider how many miles you cover in the big trot over a season, or a competitive lifetime of a horse - that is a lot of wear and tear -IE - how many horses do you know that have been retired for front end issues. I know a lot.
And thats not all - consider how far in front of the main body mass a hoof needs to land. Skeletal issues (arthritis in the fetlocks and knees sound familiar anyone?) the further the hoof lands away from the body, the more braking motion required on downhills, the more time spent with that hoof supporting weight.

Tempo also is forced to decreased in conjunction with how much time that hoof is required to spend on the ground because of extension. IE less energy efficient. Why exactly?
I had to ponder this awhile, but it makes sense. If you are asking for a certain speed to be maintained in an extended trot..because as the stride increases, the tempo decreases, and the horse is required to work harder to maintain that set speed.

Another big trot issue is the scapula inhibition that occurs. this is normally caused to a large extent by the simple fact the big extended trot causes the scapula as it drops back to hit the edge of the saddle. The muscle continues to develop as the horses body builds up a defense against this issue. Resulting in the endurance neck - a dip in front and behind the withers. It's easy to mistake this for the horse muscling up- while this is true , the muscles are not developing because they are getting more fit, but in spite of.

the other thing less talked about is the engine. I was taught the engine of a horse is it's back end. while I can't prove it, I also believe an attributing factor to scapular muscle buildup, is the fact that when endurance horses are working for such long periods of time in an inverted extended trot - they aren't using their back and by default are not 'through'.

Through is the term used by other disciplines to describe a horse who is using their back end correctly, providing impulsion and suspension along their back (which is active) and into the bit (aka rider's hands) I don't see that too often in an endurance horse.

So what is my personal conclusion - the big trot has limited place in endurance.