Sport horses: nutrition, water and electrolytes

The United States Eventing Association explains the issue this way: “Nutrients such as protein, amino acids, fat sources, mineral interactions, and water intake all play a huge role in your horse’s success, in both daily training and intense competition.”

Of course, this is true for all horses, whether in the wild, at pasture or in the stables. In an article published recently in Equus Magazine, Christine Barakat draws upon her own experience and speaks to researchers, veterinarians and horse owners around the world to get an insight into different feeding practices.

From New Zealand to South Africa, Sweden to the Netherlands, and Italy and Australia to Honduras, Barakat highlights the influence of everything from local traditions – which are not always ideal – to climate conditions, and from toxic weeds to the cultural context horses live in in a country. And while Barakat’s indepth article identifies some variations in different parts of the planet, it concludes with a phenomenon that she has observed everywhere:

“While the specific types of hay and grains fed to horses may vary from country to country, the anticipatory nicker heard at feeding time is a universal language recognized by all horsepeople. That call – when a horse simultaneously says “hurry up” and “thank you” – is one of those little things that brighten a horsekeeper’s day, providing reassurance that our effort is appreciated, no matter what country we call home.”

Of course, food is just one part of the equation, and riders, owners, trainers and grooms must also have a good understanding of the hydration needs of their horses before, during and after exertion. As has been noted elsewhere, the animals can lose up to 10–15 litres of water an hour, much more than people. Given that reality, Canadian experts Dr. Mike Lindinger and Gayle Ecker at the University of Guelph in Ontario have warned that the traditional skin pinch test used to assess hydration levels can be insufficient, and the issue of electrolytes has to be taken into account.   

As Lindinger told Jackie Bellamy of Equine Guelph, “Drinking plenty of water after exercise is NOT enough!” Bellamy explains: “Water given during or after exercise dilutes the body fluid compartments and is excreted because the body senses it as volume overload. Prolonged exercise results in loss of electrolytes and depleted glycogen levels which contribute to muscle soreness and poor performance. Simply replacing water is not sufficient due to the high concentration of electrolytes (including sodium, potassium, chloride, magnesium and calcium) that a horse loses during sweating. Administration of electrolytes helps restore those essential nutrients lost during sweating.”