Feed to Succeed:Supplements for the Endurance Horse

I adore the Kentucky Equine Research Institute. Yesterday I attended a webinar by Dr. Kathleen Crandell, discussing the 10 major concepts of feeding the performance horse. I also had to admire her patience, as storms were causing her some (most likely) truly annoying technical difficulties. I'd still like to thank her for donating her time !

For many years, I found I'd settle down to read about nutritional information in regards to feeding performance horses and zzzzzz. I have known the basics for years, but reading page after page of what THIS supplement can do for your horse- just made me want to cry, along with the overpowering headache I would achieve.

Now that I'm older, and hopefully have a longer attention span, I find I can march through a bit more of it at a time, and then.. yep.. zzzzzz

So I cheat now. Between KER and MSU's eXtension portal - and their research papers/webinars and podcasts- there is a veritable mountain of information available.

Given the unique demands of our sport, and the need to maintain our horses in top physical condition - it certainly behooves us as both horse owners and competitors to take full advantage of the valuable information so willingly given out by these institutions.

Which brings me to my post (finally you all say)
KER:

Feed to Succeed: Supplements to Help the Endurance Horse

The endurance horse is unique among all other equine athletes. Because of the prolonged demands placed upon the endurance horse with protracted moderate intensity exertion, its performance may be influenced quickly by the quality of its diet. A simple diet of hay and oats may lack essential nutrients that allow the horse to perform as expected. Understanding how competition affects the nutrient needs of the horse will help the owner select the appropriate supplementation program for the individual endurance horse.

Improving the diet
Approximately 80 to 90% of the feed eaten by horses is used to satisfy their energy requirements. Horses, like people, utilize energy to run most of the chemical reactions within the body, particularly to fuel muscle contractions vital to the work effort. As such, any horse diet should focus on providing adequate energy (calories). The major source of that energy is dietary carbohydrates (grass, hay, grain, molasses, etc.) Because the amount of energy available from forage alone can be a limiting factor for performance, grain is often added to increase the energy density of a diet.

Dietary fat is another source of energy readily employed by the horse for calories. Fat contains roughly 2.25 as much energy as an equal weight of carbohydrate, so less is needed to fuel body processes. Dietary fat has been scientifically proven to be advantageous to the performance of horses undergoing prolonged bouts of exercise. More Here...

Glycogen Sparing Effect in Endurance Horses or Feeding Fat to the Endurance Horse

There have been several studies done on the addition of fat to endurance horse diets. Fats can be useful in 2 ways. Up to 30% of a horses total diet can be fats, or 20% of concentrates. 10% total is the most common baseline that is followed, as higher percentages are sometimes refused by the horse due to texture and taste issues.
Commonly fat has been added to a horses diet for 2 reasons.

1. To add 'bloom' or gloss to a horses coat.
2. To and or maintain weight in a horse with a large energy requirement.

The more scientific or factual reasons fats are added to a diet, that are directly beneficial to the high level endurance horse are.

1. Fat is the most energy dense feed available - considering that it is also highly digestible, energy that remains available for production is increased by 60%! Minimal amounts are lost through body functions or heat.

2. Fats decrease the heat load (meaning that the horse isn't required to use to heat to metabolize fats, unlike proteins or fibre. In a study where 10% fat was added to the horses total diets, heat production was actually reduced by 14% - hence possibly one of the reasons the monikor of 'cool calories' originated. This is an essential fact that is of high value to the endurance horse - as when processing fats in a working environment - the heat load (sweat) % is reduced as the horse relies on fats for energy.

3. The most important facet of feeding fats (and the least understood) is the glycogen sparing effect in endurance horses. In horses fed a 10% fat total diet - the horse's metabolism shifts (this takes approx 90-120 days to come into effect) whereby the horse begins to use fat stores more effectively and consistently during work periods - essentially 'sparing' glycogen.

Glycogen is the carbohydrates that are stored in the horses body - during aerobic exertion the horse use glycogen as it's primary source of energy. Fatigue becomes apparent when the horse runs out of glycogen - or is working at a rate where the horse can longer produce glycogen at the rate that is required (anaerobic activity) and/or glycogen depletion.

By having a horse's base metabolism shift to using fats as a primary energy source, glycogen is then spared - by the fact that glycogen stores are used only to burn the fat that the base energy rather than glycogen itself being the primary source of energy during exertion. Glycogen stores last longer, resulting in longer mileages available before fatigue sets in.

The horse can utilize glycogen without fats, but cannot utilize fats without glycogen. when the horses metabolism relies solely on glycogen, workout sessions will be shorter, simply due to the onset of fatigue. If a horses metabolism is shifted to relying mainly on fats, fat stores are comparatively endless.

This is an important point, so when planning to enhance an endurance horses diet with fats, the ability of the horse to create glycogen must also be accounted for.