Treatments affecting fluid and electrolyte status during exercise.

A number of feeding and management practices, dietary electrolyte supplements, and medications may affect fluid and electrolyte status in resting and exercising horses. The contents of the gastrointestinal tract of the equine athlete, unlike its human counterpart, are responsible for more than 10% of body weight. Although ingesta traditionally has been considered dead weight for the sprinting horse, it is a valuable reservoir of fluid and electrolytes that may be used during endurance exercise. Numerous strategies for hyperhydration of the equine athlete and for replacement of fluid and electrolytes lost via sweating were developed in preparation for competing in the hot and humid climate of the 1996 Olympic Games in Atlanta. These strategies have implications for all equine athletes. Medications, including sodium bicarbonate, furosemide, and acetazolamide commonly are used to enhance performance by either buffering alterations in fluid and electrolyte homeostasis or by ameliorating the effects of other conditions that may limit performance.