03/06/2026
One of the most important - yet often misunderstood - aspects of equine management is the use of electrolyte supplementation.
Horses lose electrolytes through sweat during exercise, particularly during cross-country phases, fast work and travelling. Sweat contains substantial quantities of sodium, chloride, potassium, calcium and magnesium, all of which are essential for normal muscle and nerve function. Unlike humans, horses can produce very large volumes of sweat, meaning losses can become significant even in relatively moderate British weather.
For most horses in light work, a balanced diet and free access to salt are often sufficient. However, event horses working hard, travelling long distances, or competing in warm and humid conditions may benefit from additional electrolyte support.
Sodium chloride remains the most important electrolyte replacement, and many nutritionists recommend ensuring horses consume approximately 25–50g of salt daily during periods of moderate work, rising to 60–100g per day in harder work or hot conditions.
Commercial electrolyte supplements are commonly used because they contain balanced ratios of sodium, chloride and potassium. Powdered electrolytes are typically added to feed after exercise, while syringes or pastes may be used after cross-country or during multi-day events.
Electrolytes should never be given without simultaneous access to fresh water. A horse that receives concentrated electrolytes without drinking adequately may actually worsen dehydration. For this reason, it is wise to offer both plain water and lightly flavoured water at events to encourage drinking.
Soaking feeds and feeding wet recovery mash after competition can also significantly improve hydration and recovery.
