A horse’s athletic performance can be altered or affected by many things such as genetics, training, environment, health and nutrition. In particular, nutrition can play a large role in achieving peak athletic performance in horses by providing the necessary fuels (energy). The main fuels are fats and carbohydrates, in the forms of free fatty acids and glucose. The type, intensity and duration of exercise will determine the amount of each form of fuel used. Aerobic activities (long duration, low intensity) use more free fatty acids as fuel than anaerobic activities (short duration, high intensity), which use more glucose. However, the horse is almost always using both types to some degree, at the same time. Therefore, we need to make sure that our horse’s diet contains enough energy, in the form of fat and carbohydrates, to ensure that the horse can perform like we need it to. Not only is what we feed our horses important, but how we feed our horses can be just as important. Feeding at inopportune times, or feeding too much, can be a detriment to athletic performance. We don’t want to undo all of our hard work and time spent training our horses to achieve peak performance by feeding them incorrectly.

Feeding Prior to Performance

An often-asked question is, “When should I feed my horse before exercise or a competition?” The answer depends on what the horse will eat and how it will be exercised. Research has shown that a grain meal, either with or without hay, fed two hours prior to an exercise bout similar to the endurance and speed phase of a three-day event decreased free fatty acid availability and plasma glucose concentration (Pagan and Harris, 1999). Moreover, grain meals fed three hours prior to exercise also decreased plasma glucose and free fatty acid concentrations, which serve as fuels for the horse (Lawrence et al., 1993). Limiting two necessary fuels for energy is a detriment to performance, particularly higher intensity performance such as eventing, fox hunting or racing. Additionally, feeding a grain meal two hours prior to exercise, and ad libitum hay, resulted in decreased plasma volume and elevated body weights, making the blood thicker and the horses heavier (Pagan and Harris, 1999). This also could be a detriment to peak performance. Feeding hay alone did not decrease free fatty acid and glucose availability; therefore, performance will not be limited by the decreased fuels as seen with grain meals prior to exercise. The hay alone may produce a decrease in plasma volume and elevated body weights, similar to the grain meals. However, feeding hay in small amounts may reduce the effects, and the consequences of withholding hay to stalled horses (ulcers, vices) may outweigh the effects.

“Feeding at inopportune times, or feeding too much, can be a detriment to athletic performance.”

Not only does a grain meal affect fuel availability, but it also may affect heart rate. Higher heart rates during the first five minutes of exercise were found in ponies that had consumed grain meals at 0.7% of their body weight prior to exercise (Duren et al., 1992). Similar results were seen in horses that consumed grain meals two hours prior to exercise. However, horses that were fed less than 0.5% of their body weight in grain did not have higher heart rates during an exercise bout (Lawrence et al., 1995). Higher heart rates at a given speed could have an undesirable effect on performance, as the heart would be working at a faster rate than it should. In essence, the conditioning put into a horse to decrease his heart rate at a given speed would be undone. Even though research results are inconclusive, the potential for increased heart rate should be avoided by giving the horse forage only (ad libitum or up to 1% of body weight) prior to competition.

Most of the research has focused on feeding horses a grain meal two to three hours prior to exercise, but a definitive “cut-off” time has not been established. Therefore, if a competition starts early in the morning, it is best to give the horse a last grain meal the previous evening. If competition starts later in the day, the last grain meal should be given early in the morning. Forage may be provided throughout the day in small amounts; however, if a grain meal is missed during the day, do not attempt to “make it up” during the next feeding by offering twice the amount. Offer the normal amount at the scheduled time. Most of these recommendations are applicable for intense exercise of longer duration, such as racing, polo, fox hunting and endurance racing. Most of the drawbacks to a grain meal prior to exercise, such as decreased fuel availability or increased heart rates, should not adversely affect horses in low intensity or short duration exercise, such as pleasure, equitation, or even short, timed events such as barrel racing.

Feeding After Performance

So now that we know a little bit about feeding our horses prior to performance, what about feeding them after exercise? If the horse is exercising at high intensities, or for long durations, it is imperative that it receives forage and grain (if needed) after a bout of exercise, particularly if it is competing for multiple days. Concentrates should be fed two hours after intense exercise. Feeding forage and grain following an intense or long duration bout of exercise is essential to restoring glycogen (stored carbohydrate) pools in the liver and muscle. Glycogen is a primary fuel for exercise, and is comparable to gasoline for automobiles. Once the gasoline runs out, the car stalls. Once glycogen is depleted during exercise, the horse fatigues and can no
longer continue. Thus, it is very important for horses that compete over multiple days, such as eventers, endurance racers or competitive trail horses, to replenish their depleted glycogen stores so that they have enough “gasoline” to perform the following day. However, it takes several days of rest, relaxation and adequate carbohydrates to completely refill the “gas tank.”

General Feeding Management

As with all horses, it is important to feed a balanced ration to a performance horse. Improperly balanced rations can lead to a decrease in performance, metabolic stress and digestive upsets. Be sure to either purchase commercial feed designed for performance horses or formulate specialized feeds with the assistance of an equine nutritionist. Assuming a horse is healthy, sound and disorder-free, and is consuming a balanced ration, most supplements are not needed and are simply a waste of money; they could also potentially cause problems such as detrimental mineral interactions and toxicities. Possible exceptions to this may include joint and ulcer medications/supplements. If the horse is unwell, it is best to work under a veterinarian’s

Another exception to supplements is electrolytes. Horses working under hot and humid conditions for long periods of time and sweating excessively may need some form of electrolytes. Horses lose a lot of minerals through sweat, and those need to be replaced. Horses that sweat heavily during exercise may not be able to recoup the lost minerals through their normal diet, and may require a dose of electrolytes. Electrolytes come in various application forms, such as a paste or granules to be added to feed or water. It is not recommended to put the electrolytes in the water, as this will make the water rather salty and the horse may not want to drink it. Providing electrolytes in a paste will ensure the horse receives the proper dose in a timely fashion, and won’t affect water intake, which can be difficult to control. Furthermore, electrolytes should only be provided when the horse is sweating excessively, as horses cannot store the electrolytes and excess electrolytes will be excreted. Horses that are not sweating heavily usually can replace their electrolyte loss through their normal diet.

Nutrition can play a key role in achieving peak performance. Fat supplementation may increase the time to fatigue, reduce the amount of carbohydrates needed and help horses get a beautiful, shiny coat that sparkles under arena lights! Timing of feeding is also crucial to performance since grain meals fed too close to performance can lower necessary fuels and possibly increase heart rates. We must always strive to keep our horses in prime condition. Perfecting our feeding strategies will help us maximize our training and conditioning programs and keep our horses in peak physical condition.


  • No make-up meals. Keep meal sizes the same and do not double-up following performance.
  • High intense exercise requires feed within two hours following activity to refuel.
  • Keep all rations balanced.
  • Most supplements are unnecessary, but electrolytes do help replenish lost minerals.
  • A body condition score of five is appropriate for most equine athletes.
  • Fat supplementation may increase the time to fatigue.

Feeding Strategies for Peak Performances in Horses, UGA Bulletin #1365

Dr. Kari Turner, UGA Equine Specialist

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