Electrolytes for Horses

It’s not just water that needs to be replenished during exercise in hot weather. Horses working for prolonged periods in hot weather lose electrolytes as well. Photo: horses by Amy the Nurse on flickr/CC BY-ND 2.0

Ever wonder why sweat tastes salty? It’s because sweat contains dissolved body salts and minerals known as electrolytes. These invisible but important ingredients conduct the body’s electrical impulses and regulate vital internal functions such as heartbeat, smooth muscle contraction (needed for gut motility) and hydration.

Electrolytes consist of sodium, chloride, potassium, calcium and magnesium, which are generally available in adequate quantities from a balanced diet. Under normal conditions, a horse or a person can replenish lost electrolytes by simply eating and drinking.

But during prolonged activity, especially in hot weather, electrolyte loss can lead to fatigue, muscle weakness, cramping, dehydration, diarrhea and metabolic failure. That’s why it is important for both horse and rider to stay hydrated and nourished during extended summertime exercise. Riders can carry a sports drink and energy bars to keep their electrolytes up to par. Horses can also benefit from commercial electrolyte supplements if they are going to be ridden for more than a few hours at a time under hot or strenuous conditions. Get your vet’s advice on using supplemental electrolytes made just for horses.

Prepackaged electrolyte pastes can be administered with a syringe at the back of the tongue, just like a dewormer. Some competitors prefer to prepare their own mix and stir it into a grain mixture, or a syringe full of applesauce or tapioca pudding. Generally, the electrolytes should be administered before activity begins, with subsequent doses given after each water break. The salty taste actually stimulates some horses to drink more, which further protects against dehydration.

Administering electrolytes post workout will help the body’s functions return to normal, aid digestion and reduce muscle fatigue. This is particularly important in events that require multi-day exercise, such as an endurance ride or cross-country event. In these situations, your horse will not be able to recover lost electrolytes fast enough through regular food and drink. Always make sure that plenty of fresh water and hay is available after administering the electrolytes at the end of the day.

Further Reading
Seasonal Feeding
Summer Sweat

The author lives in hot and sunny California.